Neuron

Approximately 80% of people who experience depression are currently not receiving any treatment. This statistic Is sad because depression Is one of the most treatable Illnesses. If treated with the proper medication and or therapy, 80% to 90% will find relief. By the year 2020, depression will be the second most common health problem in the world (SYS). I believe depression to be a very Interesting topic because as common as depression is, there is still a stigma attached to “being depressed. ” I currently suffer from depression and would like to know more about it and the different treatments that are available.

In this study, I will explain, discuss, and elaborate upon the point of view, assumptions, strengths, and weaknesses of the biological perspective on depression. The biological perspective focuses on how the brain functions and the influence of genetics on behavior. Therefore, the biological perspective explains depression as it relates to the functions of the brain. There are roughly ten million cells, called neurons, In your brain and each neuron connects to another neuron. When the connection is made, it is in the form of an electrical impulse which travels down the connections between neurons.

The neurons that carry these electrical impulses contain small gaps called synapses. These are important because they allow electrical activity, and hence brain functioning, to take place. In order for an impulse (or message) to go from one neuron across the synapse to another neuron. A number of important enzymes, called neurotransmitters, have to come into play. In total there six different groups of neurotransmitters and each one is specific to a particular type of brain cell. From the point of view of depression, the main neurotransmitters are serotonin and noradrenalin, sometimes called morphogenesis Priest).

When we are depressed, physical changes take place within our bodies. The most Important of these changes takes place within the brain. It Is on this basis that depression is considered a physical illness, rather than merely something psychological or something that exists only in the imagination or perception of the ‘OFF sufferer (Pretest). I nerve Is a null degree AT variation among people Walt depression In terms of symptoms, course of illness, and response to treatment, indicating that depression may have a number of complex and interacting causes.

These varying actors pose a major challenge to researchers attempting to understand and treat the disorder (Psych Central). However, recent advances in research technology are bringing National Institute of Mental Health (NIMH) scientists closer than ever before to characterizing the biology and physiology of depression in its different forms and to the possibility of identifying effective treatments for individuals based on symptom presentation.

People who suffer from depression have low levels of these two neurotransmitters, and this is thought to lead to the main symptoms of low mood, owe-energy, depressed outlook on life, disturbed sleep and a low drive or arousal which relates back to the definition of depression. The strengths of the biological perspective that relate to depression are the fact that depression is mainly a result of low levels of certain neurotransmitters. Another reason could be an imbalance of hormones, which would explain why nearly twice as many women as men are affected by a depressive illness each year.

The influence of hormones on depression in women has been an active area of NIMH research. One recent study was the first to demonstrate that the troublesome depressive mood wings and physical symptoms of premenstrual syndrome (MS), a disorder affecting 3% to 7% of menstruating women, results from an abnormal response to normal hormone changes during the menstrual cycle. The hormonal system that regulates the body response to stress is the hypothalamic-pituitary-adrenal (HAP) axis. It is overactive in many patients with depression.

The hypothalamus, the brain region responsible for managing hormone release from glands throughout the body, increases production of a substance called corporation releasing factor (CRY), when a threat to physical or psychological well-being is detected. Elevated levels and effects of CRY lead to increased hormone secretion by the pituitary and adrenal glands which prepares the body for defensive action. NIMH research suggests that persistent over activation of this hormonal system may lay the groundwork for depression.

The elevated CRY levels detectable in depressed patients are reduced by treatment with antidepressant drugs or ACT, and this reduction corresponds to improvement in depressive symptoms [ (Psych Central) In the sixties, the biological perspective became dominant due to numerous breakthroughs in genetics, psychopathology, neurophysiology, and brain research. Genetic research has also been able to show support that biological elements play a strong role in depression.

Close relatives of people who suffer from depression were found to be more susceptible to depression in comparison to people of the general population. There has been extensive research done on trying to identify the gene that causes depression. However, it has been hard to identify the gene and researchers feel that there are several genes that contribute to depression, meaning that each gene makes a small contribution. Psychopathology provides more evidence that the biological perspective is the primary Doctor In oppression. Ever ten past cache, targeted rug eagles NAS lea to significant advances in the pharmacological management of depression. In the sass the introduction of the selective serotonin eruptive inhibitors (Girls), into clinical medicine was heralded as the “first class” of antidepressants with a selective action on a key neurological target in depression, namely serotonin. The selective serotonin eruptive inhibitors (Girls) are the most widely used antidepressants cause they are easy to use, and their side effects are better tolerated than those of older antidepressants.

The most frequently used Girls are Florentine (Approach), serialize (Zloty), parenting (Paxar), and Catalonian (Clean). A newer antidepressant is ventilating (Officer), which is closely related to the Girls. Antidepressant medications take several weeks to be clinically effective even though they begin to alter brain chemistry with the very first dose. Research now indicates that antidepressant effects result from slow-onset adaptive changes within the neurons.

The fact that a depressed person can take an antidepressant and feel better proves that depression is mainly the result of the biological perspective [ (“Pharmacology and Depression” Pumped. Gob) Neurophysiology is a branch of clinical psychology that studies how the brain and nervous system affect how we function on a daily basis. Unlike the use of normalizing techniques such as MR., CT scans and Egg’s where the focus is on nervous system structures, neurophysiology seeks to understand how the various components of the brain are able to do their Jobs.

Clinical neurophysiology makes SE of various assessment methods to ascertain function and dysfunction and applies this knowledge to evaluate, treat, and rehabilitate individuals with suspected or demonstrated neurological or psychological problems [ (Rightful. Com) In the past decade, there have been significant advances in our ability to investigate brain function at multiple levels. The National Institute of Mental Health (NIMH) is collaborating with various scientific disciplines to effectively utilize the tools of molecular and cellular biology and genetics.

Modern brain imaging technologies re revealing that in depression, neural circuits responsible for the regulation of moods, thinking, sleep, appetite, and behavior fail to function properly, and that critical neurotransmitters, chemicals used by nerve cells to communicate, are perhaps out of balance [ (Psych Central) The weaknesses of the biological perspective are that it does not take into account your environment, society, and culture. The behavioral perspective explains mental illness as a learned response to stimuli. From a behavioral perspective, learning theorists assume that depression and the lack of reinforcement are related.

Most researchers think that depression results from an interaction between the person’s biological characteristics and psychological vulnerability and the occurrence of stressful events in his or her life [ (Huckleberry) The socio-cultural perspective describes depression as the result of social, economic, and cultural factors. Strong evidence of this is shown among people living in poverty. In addition, there are other factors, such as today’s high rate of unemployment and victims of social disasters like war. In ten manliest perspective, a person’s Taller to Tina meaning In Tie or to lawful their potential can be attributed to depression.

Abraham Mascot was an American psychologist who was best known for his theory of human motivation, which led to a therapeutic technique known as self-actualization. Mascot proposed that an individual is motivated by a hierarchy of needs. A humans basic needs must be met before higher ones can be satisfied. Arranged in order from lowest to highest in a hierarchy, the needs are physiological (satisfaction of hunger and thirst), safety (security), belongingness and love (being loved, avoiding loneliness), esteem achievement, recognition, self-esteem), self-actualization (realization of one’s full potential).

Mascot also believed that the achievement of self-actualization is often marked by peak experiences, feelings of incredible peace and happiness in the course of life activities. When these, hierarchy of needs that Mascot talks about are not met like being lonely, having low self esteem, and not reaching ones full potential in correlation with the biological factors, you have a recipe for depression. Carl Rogers, a clinical psychologist, used the theory of self-concept, which he defined as n organized pattern of perceived characteristics along with the values attached to those attributes.

He also assumed that within each individual there is a biological drive toward growth of self-concept, which can ultimately lead to self-actualization. Rogers believed that while children’s self-concept is developing, they may internalize conditions of worth, Judgments about the kinds of behaviors that will bring approval from others. He felt that to promote growth and development, parents and authority figures should give a child unconditional acceptance and love, which allows a child to evolve self-acceptance and to achieve self-actualization.

To help his clients get back on the road to self-actualization, he developed a therapeutic approach called client- centered therapy, in which the therapist offers the client unconditional positive regard by supporting the client regardless of what is said. The warm, sympathetic therapeutic environment allows the client to be freed of internalized conditions of worth and to resume the self-actualization process [ (Huckleberry) In conclusion, by exploring the different psychological perspectives, I had to take y blinders off in order gain a greater understanding of depression and how it relates to the perspectives.

Cerebral Cortex and Phineas Gage Debbie Mintz PSY 360 July 25, 2011 Phineas Gage Paper Phineas Gage was a man who was a leader at his job and was a very likeable person. His family and friends agree that he would helpful to anyone, he was happy, and easy-going person. Then he received brain damage to his cerebral cortex, which is one’s cognitive functions are within their lobes located in the brain. Humans have four kinds of lobes located within the cerebral cortex that do different functions.

Human Brain The human brain is covered with tissue known as the cerebral cortex, which large furrows (fissures) and small furrows (sulci), and there are ridges between the fissures and sulci known as gyri. Under the cerebral cortex tissue are four lobes, each lobe has a role in a humans cognitive functions. Phineas Gage was a man who received brain damage, and one will be able to see how it affected his cognitive functions. Four Lobes for Cognitive Functions

Basically the cerebral cortex is divided into four lobes; because during development of our brain the pressure divides the area into four areas and the development of these lobes do different functions within our brain. The four lobes are known as frontal lobe, temporal lobe, parietal lobe and the occipital lobe (Pinel, 2009). One’s occipital lobe is what gives him or her visual input and helps guide their behavior, the occipital cortex with “large areas of an adjacent cortex perform this cognitive function” (Pinel, 2009, p. 69).

In, the parietal lobe it has two large functional areas, the post central gyrus function, which it analyzes sensations one can feel from his or her body, such as touch. In the posterior section of the parietal lobes has the role of “perceiving the location of both objects and our own bodies and in directing our attention” (Pinel, 2009, p. 69). The cortex of one’s temporal lobes, which has three functional areas. For one’s language and hearing there is the superior temporal gyrus, the inferior temporal cortex identifies ones complex visual patterns, next is the medial ortian of the temporal cortex its cognitive function is for memory. The last of the four lobes is the frontal lobe, and it has two distinct functioning areas. The first area is the pre-central gyrus along with the adjacent frontal cortex have a motor function, and the “frontal cortex anterior to motor cortex performs complex cognitive functions” (Pinel, 2009, p. 69), such as assessing the outcomes of possible patterns of behavior, preparation to reply with sequences, and assessing the signifince of the behavior of others (Pinel, 2009).

Summary of what each lobe does •Occipital lobe for vision processing •Parietal lobe for movement, perception to stimuli, recognition, orientation. •Temporal lobe for perception and recognition of auditory stimuli, speech, and memory. •Frontal is for reasoning, parts of speech, movement, planning, problem-solving, and emotions (Brain Structures and their Functions, 2005) Phineas Gage (1823-1860)

Phineas Gage is a good example to use when explaining what happens to a person who receives brain damage and how the damage can affect ones cognitive functions. At the age of 25 a young man’s life changed completely, Phineas Gage was a hard worker as well as the a supervisor for the crew he worked with, his or her job was to blast huge rocks to make the land ready for the railroad track in 1848. His job consist of using a tampering iron on the boulders that had gun power or dynamite in them to explode, accidents do happen, and Phineas Gage received a tampering iron exploded into his face.

It was remarkable that he was alive as well as being able to walk three miles to find medical help. The doctor cleaned him up with amazement that he lived through this damage to his brain. From the doctors report the tampering iron made entry in the cranium and passed through the anterior left lobe, and made its exit in the medial line, along his sinus fracturing his frontal and parietal bones widely, substantial parts of the brain broken up and his left eye globe was protruding out the socket, within a half of a diameter (Mo, 2006).

After this terrible accident according to (Mo, 2006), Phineas Gage retained full possession of his reason, but Gages wife, family, and friends began to see dramatic changes happening to him and his personality. Even the company he worked for tried to rehire him, but they could not because his behavior changed, he was mouthy, unpredictable, disrespectful, and grossest profanities. These was not Phineas Gage’s behavior before the tampering iron went through his brain and rearrange his cognitive function from his anterior left lobe (Mo, 2006).

Which is located in the frontal lobe, and it is for reasoning, parts of speech, movement, planning, problem-solving, and emotions (Brain Structures and their Functions, 2005). This was not the Phenias Gage they knew; in fact anyone that knew Gage before states there is a drastic change to his mind. As a result of Phineas damage from his frontal cortex there was a complete loss of social inhibitions, and inappropriate behavior (Mo, 2006). To this day “the role of the frontal cortex is involved in personality changes and social cognition” (Mo, 2006, p. ) Phenias Gage lived a different life as a stable person, at a place where he was not known, presumably somewhere in Chile and live 13 more years. This shows that when one’s brain has damage that they can live through it, but as a different person. Ones cognitive functions can become altered by brain damage within their lobes in their brain. Phineas Gage he seemed to turn from a good natured person to a bad natured person, does that mean a bad natured person can become altered to a good natured person?

Keep in mind that I am looking at your exam questions while writing the study guide. Be sure you know what the terms are, how they have been researched, and describe your answers In your own words. I decided to limit your test to the first three chapters. You can do quite well focusing on the material below. Enjoy! Why is drug withdrawal a painful experience for addicts? Using drugs puts an excess amount of neurotransmitters in the body.

When there is an overflow the brain stops making it naturally and when the drug wears off it takes mime for the brain to star making the chemical once again on its own system. Some neurotransmitters are dopamine, serotonin, Acetylene’s, Morphogenesis, Gamma- nonparametric acid, Endorphins. Endorphins are natural opiates. Brooch’s area and Wrinkle’s area in the brain and their responsibilities. B- speaking W-understanding What does It mean to be randomly assigned? The design of a study such that all subjects have an equal chance of being assigned to any group or condition.

What does it mean to be debriefed? A discussion of procedures, hypothesis. And subject reactions at the completion of the study. Explain what a correlation is and its mathematical representation. A correlation exists when 2 variables are related to each other. May be positive or negative depends on nature of the association between the variables measured. Correlation Indicates the 2 variables that change together In the opposite direction. Strength of correlation depends on size of coefficient.

Be very clear about the difference between correlation and causation. What is responsible for carrying information from the central nervous system to tissue? What s an independent and dependent variable? What do we know about Alchemist’s disease, schizophrenia and neurotransmitters? Alchemist’s brains show to have low levels of ACH-Acetylene’s. Schizophrenia is linked to excess levels of dopamine. What Is an agonies/antagonist and how do they work? Chemical that mimics the action of a neurotransmitter.

Antagonist *jiff]: Chemical that opposes the action of a neurotransmitter. Agonies works with the muscles, and the antagonist is the muscle working against it Know all of the various schools of psychology and their arguments. Structuralism was eased on the notion that the task of psychology is to analyze consciousness into its basic elements and investigate how these elements related. Functionalism was based on the belief that psychology should investigate the function or purpose of consciousness, rather that it’s structure.

Natural selection inherited characteristics that provide a survival or reproductive advantage are more likely the alternative characteristics to be passed on to subsequent generations and thus come to be “selected” over time. Behaviorism is a theoretical orientation based on the premise that scientific psychology should study only observable behavior. Humanism is a theoretical orientation that emphasizes the unique qualities of humans, especially their freedom and their potential for personal growth. What is research replication and why do it?

The repetition of study to see whether the earlier results are duplicated. What were the Greek philosophers interested in discovering? Know our policies described on our syllabus well. Know the key points and messages of ALL of our video presentations; Know all of the research methods discussed in class along with their strengths and weaknesses. What is the magical responsible for? What comprises the limbic system, endocrine system, sympathetic nervous system, peripheral nervous system & central nervous system.

Limbic systemic: Thalamus, Hypothalamus, Hippopotamus, and the magical. Endocrine systemic>?k G: Group of glandless* that secrete”Z chemicals into the bloodstream that help control bodily function. Sympathetic nervous immobilizers the body resources for emergencies. Peripheral nervous all those nerves that lie outside the brain and spinal cord. Central nervous G: Brain and spinal cord. How do neurons communicate? Axons and dendrites carry information to and from the cell body. Neurotransmitters send signals chemically between neurons.

What is the placebo effect? According to ancient Greek civilizations, what is psychology? A definition for a topic of study. Psyche was used to refer to the soul, spirit, or mind, as distinguished from the Know all of your brain lobes, their location and their responsibilities. Frontal lobes: speaking, muscle movements, making plans, Judgments Parietal lobes: sensory area Occipital lobes: vision Temporal lobes: auditory In order to measure either a physical or mental construct, what criteria must the measure meet?

Mean, median, mode they have been researched, and describe your answers in your own words. I decided material below. Learn a lot and earn an A. Enjoy! Why is drug withdrawal a painful experience for addicts (hint: What are the brains’ natural opiates called)? Text & Lecture Your brain stop produce dopamine… Because the drug give too much… And when you stop taking them. There are no dopamine left What does it mean to be randomly assigned? Text & Lecture Randomly select object or….

It can generalize the whole population that represent chi What does it mean to be debriefed? Text Ex: give you the different reason for certain study… And tell you the truest after Explain what a correlation is and its mathematical representation. Text & Lecture Ex: something cause other things to happen… A cause B… Ex: not study cause bad grade… Mathematical representation—positive +1 no correlation negative correlation -1 as the research close to O, that means it have no correlation What’s the relationship between ice cream sales and pool drowning?

Lecture Relation between this too is summer. Cause more sale in ice cream, the more people go swim and more people drowning. A- ice cream b-PDP C heat c cause A and B so more B=more What is an independent and dependent variable? Text & Lecture Independent-music they listen dependent- how many world they memorize (amount that been measure) to Lecture Alchemies – schizophrenia-have ex dopamine or lack neurotransmitters (page 75)(he like to test drugs and what effect) What is an agonies/ antagonist and how do they work?

Lecture Agonies- keep the reaction going antagonist-stop the reaction going (ex antagonist can stop the pain) Know all of the various schools of psychology and their arguments?structuralisms, Functionalists, Behaviorist’s, etc. Lecture Structuralism- need name v…… First school in German-take what you have experience and break down-(ex what make you anger) Functionalism- …. James – ex(why people drop out school… ) stall-study the whole not parts of the brain he study dreams… Hypnoses John Watson-more about behavior and something that can measure skinner-rewards and punishment

Empirical analysis of internet user in Dhaka city BY Md. Faisal BBA (Studying) 4th year Major in International Business Faculty of Business Studies University of Dhaka Email:faisal. ib15@gmail. com Customer Analysis A questionnaire survey method has been used to analyze the customer of internet services in Dhaka city. We basically tried to find the percentage of internet user, using pattern, nature of expenditure, satisfaction level, and the opportunity for a new business to enter into the market. The percentage of internet user in Dhaka City

Among all respondents of our survey, 78% people use internet and the rest 22% do not use internet. This is given in the following graph: Figure1. 1: The percentage of internet user in Dhaka City From the above figure, we can easily understand the percentage of internet user in Dhaka City. Among all 78%user, majority are students, businessman, and private employee. On the other hand among all 22%non user, majority are government employee, small and medium (SME) business owner. Using pattern There are many internet services provider in Dhaka City that provide different internet package. As a result the using pattern of people is different.

Using pattern can be divided into the following categories: A) Forms of internet used by the people B) Brand preferences C) Package preference A) Forms of internet used by the people Internet can be divided into different forms. These are: (A1) Broadband internet (A2) Wireless Modem (A3) Mobile Internet (A4) Wi-Fi In Dhaka city, people use different forms of internet. The graphical figure of different forms used by the people is given below: Figure: 1. 2 Forms of internet used by the people (%) The figure (1. 2) shows that 74% people use wireless modem, 17% use broadband internet, 7%use mobile internet and 2% use Wi-Fi.

This figure clearly mentions that people prefer wireless modem over broadband internet. The reasons are the following: (1)Wireless modem internet provides better speed than broadband. (2)Low connection Cost (3)Prepaid package (4)Suitable for both Desktop computer and the Laptop The people specially the university student have the facility to use Wi-Fi. The Wi-Fi coverage area is very limited in Dhaka City. Some people also use mobile interne B) Brand preferences Many companies in Dhaka city provide internet services. These are the followings: A)Broadband Services provider B)Banglalion Wimax C)Qubee D)Citycell E)Airtel

F)Robi G)Banglalink H)GP People use Different Brand. Brand preferences are shown in the following graph: Figure: 1. 3 Brand Preferences The above figure shows that 17% people use broadband internet,30%use banglalion wimax,23%use qubee,7. 5%use citycell ,2. 5%use airtel,and20. 51%use Grameenphone (GP) internet. We can say from our survey that top two brands are banglalion and qubee. Others are the broadbandservics provider, GP, citycell and the airtel. C) Package preference There are many types of internet packages are available . People use different package based on their demand, cost structure, and brand preferences.

The following graph shows the different packages used by the people: Figure: 1. 3 package preferences According to the figure 1. 3, it is clear that 43. 5%people use unlimited package, 7. 39%people use internet minipac, 5. 51%people use a package that has limitations of more than 800MB. 35. 56% people use 800MB-1GB package, 7. 69% use 1-2. 5GB package. And 2. 56% use other package. Basically business man and rich people prefer unlimited package. On the other hand students and low income group normally prefer the rest of the package. So 56. 5% do not prefer unlimited package.

So the internet services provider of Dhaka city must be careful about this issues while developing new packages. 3. 3: Nature of Expenditure Expenditure for using internet services can be divided into two parts. These are: 1. Initial Connection Charge 2. Monthly using charge 1. Initial connection Charge: If anyone wants to use internet services, first they have to pay for their connection. Connection charge varies from company to company. In Dhaka city the range of connection charge is BDT 1000-3500. 2. Monthly using Charge: Monthly using charge depends on the internet packages which are used by the internet user in Dhaka city.

The following table shows the monthly for different packages: Packages Monthly Payment UnlimitedMore than 1000 taka Minipac internetLess than 250 taka 450MB-800MB250-300 taka 800MB-1GB300-350 taka 1GB-2. 5GB350-600taka 2. 5-5GB600-750taka Table 1. 1: Monthly using charge From table 1. 1 we have found that there is a correlation between the internet packages and monthly payment. When the using volume increases the monthly expenditure also increases. 3. 4: Satisfaction level When the people were asked whether they satisfied or not about their internet services, majority replied that they are not satisfied.

The following figure shows the satisfaction level of the internet user in Dhaka city: Figure 1. 4: Satisfaction level of the Internet User in Dhaka City The above figure shows that 71. 79% internet users are dissatisfied with their current package. The rest 30. 76% are satisfied. The main reasons of Dissatisfaction are the slow browsing and download speed. From our survey, we found that 96% people get browsing speed less than 256kbps. Only 4% people get browsing speed more than 256kbps. In case of download speed, 30%people get speed less than 20kbps. 35. 89% people get the speed which range is 20-50kbps. 30. 6% people get the speed which range is 50-80kbps. And 5. 12% people get speed more than 100kbps. Because of these slow speeds the internet user has to spend long time to download anything from internet. It also increases their opportunity cost. So they are dissatisfied. Opportunity for a new business to enter into the market: “Is there any opportunity for a new business to enter into the market? ” the answer is yes. The following arguments support this answer: Among all respondents of our survey, 78% people use internet and the rest 22% do not use internet. The user rate is very high. So we can say that the market is potential.

Demand is there. Through analysis this demand, a new firm can enter into the market. When the people were asked whether they satisfied or not about their internet services, 71. 79% replied that they are not satisfied. But still they are using internet services. They want to get better. All will prefer high speed internet services. About 67. 85% people suggested to have unlimited packages and they are ready to pay on an average 750 taka per month for their packages. About 32. 15% people suggested having minimum 3GB internet packages and they are ready to pay on an average 350 taka per month for their packages.

They are ready to switch their services if any company can satisfy their demand. If a new firm can think that they will satisfy the needs of the customer, they can easily enter into the market. The market is really potential. Many people do not use internet because of their low income level. The price of desktop computer or a laptop is high. But recently Bangladesh has produced its own laptop and notebook at more reasonable prices. The brand name is DOEL. Still now it is not available in the local market. Recently our government has said these laptop and notebook will be available in the market as early as possible.

When these will be available in the market, the computer user will be increased. As a result the internet user will also be increased. So it will become an opportunity for a new business to enter into the market. The need of information is increasing rapidly. Internet is the major sources of information. Increasing information needs can be a major opportunity for a new business to enter into the market. The use of internet to market, sells, promote, or buy a product or services are increasing rapidly. This may be another opportunity for a new business to enter into the market.

Addiction psychology has made a great impact on the field of biological psychology, especially when it comes to subjects such as psycho-pharmacology. The abuse of prescription pain medicine has risen to an estimated 9 million in America alone who take the medication for non-medical reasons. The psychology field has had a new revolution in addiction control called Suboxone. In order for psychiatric doctors or other doctors to prescribe this medicine they are required to complete a training course on the substance.

Rapidly replacing Methadone, a more traditional detox and maintenance drug used for many years, Suboxone seems to have many treatment advantages over it. Buprenophine, the chemical compound found in Suboxone has stated that it is suitable for people who still have social ties to their families and employers whereas. Methadone is suited best for those who need additional structure in their treatment with more supervision.

While it is nearly impossible to overdose on Suboxone due to its ceiling effect, Methadone is easily abused as it is a full-agonist opiate. Another advantage that Suboxone has over Methadone is it readability. Where patients must go to Methadone clinics for dosing, doctors can prescribe Suboxone for a month at a time, allowing patients to detox and maintain their treatment. Buprenophine is available in two pill forms, one without Naloxone-called Subutex, or one with Naloxone-called Suboxone.

Naloxone is a well known opiate antagonist, that when injected, causes instant withdraw in the patient. Putting this ingredient as an additive with Buprenophine keeps the drug from being abused. Buprenophine is usually prescribed for just a few weeks, but some patients may need maintenance doses depending on their opiate usage and/or dependency. In order to better understand the way Suboxone and other opiates work within the central nervous system individuals should understand post-synaptic potentials, synaptic ransmission, the receptors that produce and regulate behavior (including abusing opiates), as well as understanding and knowing the primary neurotransmitters and their role in brain function and behavior.

Excitatory and Inhibitory Post-synaptic Potentials

The role of excitatory and inhibitory post-synaptic potentials is summed up by NCBI Bookshelf (n. d. ;  “Postsynaptic conductance changes and the potential changes that accompany them alter the probability that an action potential will be produced in the postsynaptic cell. Post-synaptic Potentials decrease the probability that the post synaptic cell will generate an action potential. PSPs are called excitatory (or EPSPs) if they increase the likelihood of a postsynaptic action potential occurring, and inhibitory (or IPSPs) if they decrease this likelihood.

Given that most neurons receive inputs from both excitatory and inhibitory synapses, it is important to understand more precisely the mechanisms that determine whether a particular synapse excites or inhibits its postsynaptic partner. “

Synaptic Transmission and Receptors Producing and Regulating Behavior

Neurons communicate through synaptic transmission. The synapse can be found as a tiny gap found in the middle of the axon terminal and the neuron next to it. Neurotransmitters are chemical substances that are located in synaptic vesicles are responsible for delivering messages across the synapse and bind to the receptor sites. When a molecule of a neurotransmitter binds to the receptor it then continues to activate or inhibit the neuron until the deactivation occurs. A method of deactivation is called re-uptake, allowing the neurotransmitter molecules to be delivered back to| |the presynaptic neuron. Various drugs, including opiates such as hydrocodone or methadone function as agonists because they increase the activity of the neurotransmitter while others such as Naloxone act as antagonists decreasing the activity of the neurotransmitter.

Primary Neurotransmitters

The three major neurons located in the nervous system are the sensory, motor, and inter-neurons. Sensory neurons are responsible to input messages from the sense organs to the spinal cord and brain. Motor neurons carry impulses from the brain and spinal cord to the muscles and organs. Interneurons perform connective or associative functions within the nervous system. The brain and spinal cord are called the central nervous system while all neurons that connect the CNS to the muscles, glands, and sensory receptors are located in the peripheral nervous system.

In this regard, the PNS is divided into two systems:the somatic nervous system that includes sensory and motor neurons, and the autonomic nervous system required to| |regulate glands as well as other involuntary functions such as circulation, breathing, and digestion. The autonomic nervous system consists of two branches as well. The sympathetic branch activates or arouses bodily organs while the parasympathetic branch does the complete opposite. Most nerves enter and leave the CNS via the spinal cord.

How often have you fallen prey to procrastination? After all, there is a tomorrow always isn’t it? But then after these pangs of procrastination, all that we end up feeling is sheer guilt of wasting time. So what can be done to avoid the prerequisite procrastination and add more productivity to the day? Follow these basic steps –

1. Make notes: Planning out the work that you wish to do tomorrow and making notes of it in a way sets alarm to your brain. Once you wake up after your good sleep prepare the list. Do not over stuff it in the beginning rather keep it short but ensure that you complete each and every task you have planned. Making these notes in the morning prepares your brain for the long day ahead.

2. Set deadlines: A lot of fooling our brains by making it sense of emergency. The theory is such that, when you set a deadline for yourself stringently, you are more likely to complete the task on time without giving yourself a chance to procrastinate. Try setting up the deadlines for yourself for each task that you take up.

3. Timings: Often detaching ourselves from all kind of distractions distracts us even more. So instead of pledging that you will not surf on twitter or Facebook, you can simply set limits. Limit the time that you spend watching TV or any social media side but don’t completely cut it.

4. Prioritizing: Lack of prioritizing the work becomes one of the reasons why things go disorganized and your end up procrastinating them. Look at your things-to-do list carefully and try to segregate the tasks. You need to see what the task that would take more time are and what are the less time-consuming ones. The prioritization helps you in conserving your time in a much smarter way.

5. Productive hours: Everyone has a set of hours on a day when they are the most productive. Try figuring out the hours that are favorably productive to you and complete the most dreaded task of the day in the set of hours. Similarly, there are unproductive hours of the day too, here plan out the of the day. In this way, you would be utilizing your productive as well as unproductive hours like a pro!

6. Learn to say NO: Most of us find it tough to deny a task given due to whatsoever reason but that ends up effective upon our level of productivity. You need to understand your work capacity and then take the tasks accordingly. Learn to politely decline the tasks that you find tough to complete in the given time p.

These minor changes in your routine would surely enhance the level of productivity that you exude. Keeping a tap on the activities you spend your most of the time upon is vital. It helps you in preparing the plan and reducing it. He change would however take time, your productivity won’t shoot up in one day but eventually.

Histology Review Supplement The slides in this section are designed to provide a basic histology review related to topics introduced in the PhysioEx lab simulations and in your anatomy and physiology textbook. From the PhysioEx main menu, select Histology Tutorial. The opening screen should appear after a few seconds. The Sort by menu is located at the top left. Click on the white drop-down menu and select “Histology Review” from the list.

You will note that the slides in the histology module are grouped in the following folders: Skeletal muscle slides Nervous tissue slides Endocrine tissue slides Cardiovascular tissue slides Respiratory tissue slides Digestive tissue slides Renal tissue slides Select the group of slides you wish to view, and then refer to the relevant worksheet in this section for a step-by-step tutorial. For example, if you would like to review the skeletal muscle slides, click on the Skeletal muscle slides folder, and then turn to the next page of this lab manual for the worksheet entitled Skeletal Muscle Tissue Review to begin your review.

You will have the option of viewing slides with or without labels by clicking the On/Off buttons at the bottom left of the viewer. Since the slides in this module have been selected for their relevance to topics covered in the PhysioEx lab simulation, it is recommended that you complete the worksheets along with a related PhysioEx lab. For example, you might complete the Skeletal Muscle Tissue worksheet right before or after your instructor assigns you Exercise 2, the PhysioEx lab simulation on Skeletal Muscle Physiology. For additional histology review, turn to page 121. 23 Skeletal Muscle Tissue Review From the PhysioEx main menu, select Histology Review Supplement. When the screen comes up, click Select an Image Group. From Group Listing, click Skeletal muscle slides. To view slides without labels, click the Labels Off button at the bottom right of the monitor. Click slide 1. Skeletal muscle is composed of extremely large, cylindrical multinucleated cells called myofibers. The nuclei of the skeletal muscle cell (myonuclei) are located peripherally just subjacent to the muscle cell plasmalemma (sarcolemma).

The interior of the cell is literally filled with an assembly of contractile proteins (myofilaments) arranged in a specific overlapping pattern oriented parallel to the long axis of the cell. Click slides 2, 3. Sarcomeres are the functional units of skeletal muscle. The organization of contractile proteins into a regular end-to-end repeating pattern of sarcomeres along the length of each cell accounts for the striated, or striped, appearance of skeletal muscle in longitudinal section. Click slide 4.

The smooth endoplasmic reticulum (sarcoplasmic reticulum), modified into an extensive network of membranous channels that store, release, and take up the calcium necessary for contraction, also functions to further organize the myofilaments inside the cell into cylindrical bundles called myofibrils. The stippled appearance of the cytoplasm in cells cut in cross section represents the internal organization of myofilaments bundled into myofibrils by the membranous sarcoplasmic reticulum. What is the functional unit of contraction in skeletal muscle?

Click slide 5. The neural stimulus for contraction arises from the axon of a motor neuron whose axon terminal comes into close apposition to the muscle cell sarcolemma. Would you characterize skeletal muscle as voluntary or involuntary? Name the site of close juxtaposition of an axon terminal with the muscle cell plasmalemma. Skeletal muscle also has an extensive connective tissue component that, in addition to conducting blood vessels and nerves, becomes continuous with the connective tissue of its tendon.

The tendon in turn is directly continuous with the connective tissue covering (the periosteum) of the adjacent bone. This connective tissue continuity from muscle to tendon to bone is the basis for movement of the musculoskeletal system. What is the name of the loose areolar connective tissue covering of an individual muscle fiber? endomysium The perimysium is a collagenous connective tissue layer that groups several muscle fibers together into bundles called fascicles . the sacromeres What are the two principal contractile proteins that compose the functional unit of contraction?

Which connective tissue layer surrounds the entire muscle and merges with the connective tissue of tendons and aponeuroses? epimysium actin and myosin What is the specific relationship of the functional unit of contraction to the striated appearance of a skeletal muscle fiber? the repeating pattern of the sacromeres organized end to end 124 Histology Review Supplement Nervous Tissue Review From the PhysioEx main menu, select Histology Review Supplement. When the screen comes up, click Select an Image Group. From Group Listing, click Nervous tissue slides.

To view slides without labels, click the Labels Off button at the bottom right of the monitor. Nervous tissue is composed of nerve cells (neurons) and a variety of support cells. Click slide 1. Each nerve cell consists of a cell body (perikaryon) and one or more cellular processes (axon and dendrites) extending from it. The cell body contains the nucleus, which is typically pale-staining and round or spherical in shape, and the usual assortment of cytoplasmic organelles. Characteristically, the nucleus features a prominent nucleolus often described as resembling the upil of a bird’s eye (“bird’s eye,” or “owl’s eye,” nucleolus). Click slide 2. The cytoplasm of the cell body is most often granular in appearance due to the presence of darkly stained clumps of ribosomes and rough endoplasmic reticulum (Nissl bodies/ Nissl substance). Generally, a single axon arises from the cell body at a pale-staining region (axon hillock), devoid of Nissl bodies. The location and number of dendrites arising from the cell body varies greatly. Axons and dendrites are grouped together in the peripheral nervous system (PNS) to form peripheral nerves.

What is the primary unit of function in nervous tissue? Click slide 5. Because Schwann cells are aligned in series and myelinate only a small segment of a single axon, small gaps occur between the myelin sheaths of adjacent contiguous Schwann cells. The gaps, called nodes of Ranvier, together with the insulating properties of myelin, enhance the speed of conduction of electrical impulses along the length of the axon. Different support cells and myelinating cells are present in the central nervous system (CNS). What is the general name for all support cells within the CNS? neuroglial cells

Name the specific myelinating cell of the CNS. Oligodendrocyte In the PNS, connective tissue also plays a role in providing support and organization. In fact, the composition and organization of the connective tissue investments of peripheral nerves are similar to those of skeletal muscle. Click slide 3. Each individual axon or dendrite is surrounded by a thin and delicate layer of loose connective tissue called the endoneurium (not shown. ) The perineurium, a slightly thicker layer of loose connective tissue, groups many axons and dendrites together into bundles (fascicles).

The outermost epineurium surrounds the entire nerve with a thick layer of dense irregular connective tissue, often infiltrated with adipose tissue, that conveys blood and lymphatic vessels to the nerve. There is no connective tissue component within the nervous tissue of the CNS. What is the relationship of the endoneurium to the myelin sheath? neuron Name the pale-staining region of the cell body from which the axon arises. nucleus The support cells of the nervous system perform extremely important functions including support, protection, insulation, and maintenance and regulation of the microenvironment that surrounds the nerve cells.

Click slides 3, 4. In the PNS, support cells surround cell bodies (satellite cells) and individual axons and dendrites (Schwann cells). Schwann cells, in particular, are responsible for wrapping their cell membrane jelly-roll style around axons and dendrites to form an insulating sleeve called the myelin sheath. enclosed and protects Histology Review Supplement 125 Endocrine Tissue Review From the PhysioEx main menu, select Histology Review Supplement. When the screen comes up, click Select an Image Group.

From Group Listing, click Endocrine tissue slides. To view slides without labels, click the Labels Off button at the bottom right of the monitor. antrum, except for a thin rim of granulosa cells (corona radiata) that encircles the oocyte and a pedestal of granulosa cells (cumulus oophorus) that attaches the oocyte to the inner wall of the antrum. Which cells of the ovarian follicle secrete estrogen? Thyroid Gland The thyroid gland regulates metabolism by regulating the secretion of the hormones T3 (triiodothyronine) and T4 (thyroxine) into the blood.

Click slide 1. The gland is composed of fluid-filled (colloid) spheres, called follicles, formed by a simple epithelium that can be squamous to columnar depending upon the gland’s activity. The colloid stored in the follicles is primarily composed of a glycoprotein (thyroglobulin) that is synthesized and secreted by the follicular cells. Under the influence of the pituitary gland, the follicular cells take up the colloid, convert it into T3 and T4, and secrete the T3 and T4 into an extensive capillary network.

A second population of cells, parafollicular (C) cells (not shown), may be found scattered through the follicular epithelium but often are present in the connective tissue between follicles. The pale-staining parafollicular cells secrete the protein hormone calcitonin. Why is the thyroid gland considered to be an endocrine organ? Uterus Click slides 4, 5, 6. The uterus is a hollow muscular organ with three major layers: the endometrium, myometrium, and either an adventitia or a serosa. The middle, myometrial layer of the uterine wall is composed of several layers of smooth muscle oriented in different planes.

Click slide 6. The innermost (nearest the lumen) endometrial layer is further divided functionally into a superficial functional layer (stratum functionalis) and a deep basal layer (stratum basalis). Click slide 4. A simple columnar epithelium with both ciliated and nonciliated cells lines the surface of the endometrium. The endometrial connective tissue features an abundance of tubular endometrial glands that extend from the base to the surface of the layer. During the proliferative phase of the menstrual cycle, shown here, the endometrium becomes thicker as the glands and blood vessels proliferate.

Click slide 5. In the secretory phase, the endometrium and its glands and blood vessels are fully expanded. Click slide 6. In the menstrual phase, the glands and blood vessels degenerate as the functional layer of the endometrium sloughs away. The deep basal layer (stratum basalis) is not sloughed and will regenerate the endometrium during the next proliferative phase. Which layer of the endometrium is shed during the menstrual phase of the menstrual cycle? it secrets a horomone What hormone secreted by the pituitary gland controls the synthesis and secretion of T3 and T4? TSH – thyroid stimulating hormone

What is the function of calcitonin? causes CA to be released into blood Ovary The ovary is an organ that serves both an exocrine function in producing eggs (ova) and an endocrine function in secreting the hormones estrogen and progesterone. Click slide 2. Grossly, the ovary is divided into a peripherally located cortex in which the oocytes (precursors to the ovulated egg) develop and a central medulla in which connective tissue surrounds blood vessels, lymphatic vessels and nerves. The oocytes, together with supporting cells (granulosa cells), form the ovarian follicles seen in the cortex at various stages of development.

Click slide 3. As an individual oocyte grows, granulosa cells proliferate from a single layer of cuboidal cells that surround the oocyte to a multicellular layer that defines a fluid-filled spherical follicle. In a mature follicle (Graafian follicle), the granulosa cells are displaced to the periphery of the fluid-filled 126 Histology Review Supplement endometrium What is the function of the deep basal layer (stratum basalis) of the endometrium? regenerate new superficial layer What composes a serosa? perimetrium

How does the serosa of the uterus, where present, differ from visceral peritoneum? location Pancreas The pancreas is both an endocrine and an exocrine gland. Click slide 7. The exocrine portion is characterized by glandular secretory units (acini) formed by a simple epithelium of triangular or pyramidal cells that encircle a small central lumen. The central lumen is the direct connection to the duct system that conveys the exocrine secretions out of the gland. Scattered among the exocrine secretory units are the pale-staining clusters of cells that compose the endocrine portion of the gland.

The cells that form these clusters, called pancreatic islet cells (islets of Langerhans), secrete a number of hormones, including insulin and glucagon. Do the pancreatic islets secrete their hormones into the same duct system used by the exocrine secretory cells? no, but directly into blood stream Histology Review Supplement 127 Cardiovascular Tissue Review From the PhysioEx main menu, select Histology Review Supplement. When the screen comes up, click Select an Image Group. From Group Listing, click Cardiovascular Tissue Slides. To view slides without labels, click the Labels Off button at the bottom right of the monitor.

Which component of the intercalated disc is a junction that provides the intercellular communication required for the myocardium to perform as a functional syncytium? gap juntions Blood Vessels Blood vessels form a system of conduits through which lifesustaining blood is conveyed from the heart to all parts of the body and back to the heart again. Click slide 3. Generally, the wall of every vessel is described as being composed of three layers, or tunics. The tunica intima, or tunica interna, a simple squamous endothelium and a small amount of subjacent loose connective tissue, is the innermost layer adjacent to the vessel lumen.

Smooth muscle and elastin are the predominant constituents of the middle tunica media, and the outermost tunica adventitia, or tunica externa, is a connective tissue layer of variable thickness that provides support and transmits smaller blood and lymphatic vessels and nerves. The thickness of each tunic varies widely with location and function of the vessel. Arteries, subjected to considerable pressure fluctuations, have thicker walls overall, with the tunica media being thicker than the tunica adventitia.

Veins, in contrast, are subjected to much lower pressures and have thinner walls overall, with the tunica adventitia often outsizing the tunica media. Because thin-walled veins conduct blood back to the heart against gravity, valves (not present in arteries) also are present at intervals to prevent backflow. In capillaries, where exchange occurs between the blood and tissues, the tunica intima alone composes the vessel wall. The tunica media of the aorta would have a much greater proportion of what type of tissue than a small artery? Heart The heart is a four-chambered muscular pump.

Although its wall can be divided into three distinct histological layers (endocardium, myocardium, and epicardium), the cardiac muscle of the myocardium composes the bulk of the heart wall. Click slide 1. Contractile cardiac muscle cells (myocytes, myofibers) have the same striated appearance as skeletal muscle, but are branched rather than cylindrical in shape and have one (occasionally two) nucleus (myonucleus) rather than many. The cytoplasmic striations represent the same organization of myofilaments (sarcomeres) and alignment of sarcomeres as in skeletal muscle, and the mechanism of contraction is the same.

The intercalated disc, however, is a feature unique to cardiac muscle. The densely stained structure is a complex of intercellular junctions (desmosomes, gap junctions, fasciae adherens) that structurally and functionally link cardiac muscle cells end to end. A second population of cells in the myocardium composes the noncontractile intrinsic conduction system (nodal system). Although cardiac muscle is autorhythmic, meaning it has the ability to contract involuntarily in the absence of extrinsic innervation provided by the nervous system, it is the intrinsic conduction system that prescribes the rate and orderly sequence of contraction.

Extrinsic innervation only modulates the inherent activity. Click slide 2. Of the various components of the noncontractile intrinsic conduction system, Purkinje fibers are the most readily observed histologically. They are particularly abundant in the ventricular myocardium and are recognized by their very pale-staining cytoplasm and larger diameter. The connective tissue component of cardiac muscle is relatively sparse and lacks the organization present in skeletal muscle. Which component of the intercalated disc is a strong intercellular junction that functions to keep cells from being pulled apart during contraction? lastic fiber In general, which vessel would have a larger lumen, an artery or its corresponding vein? vein Why would the tunica media and tunica adventitia not be present in a capillary? to allow material exchange between blood and tissue desmosomes What is a functional syncytium? Because the cardiac muscle cells are mechanically, chemically, and electrically connected to one another, the entire tissue resembles a single, enormous muscle cell. 128 Histology Review Supplement Respiratory Tissue Review From the PhysioEx main menu, select Histology Review Supplement.

When the screen comes up, click Select an Image Group. From Group Listing, click Respiratory Tissue Slides. To view slides without labels, click the Labels Off button at the bottom right of the monitor. The respiratory system serves both to conduct oxygenated air deep into the lungs and to exchange oxygen and carbon dioxide between the air and the blood. The trachea, bronchi, and bronchioles are the part of the system of airways that conduct air into the lungs. Click slide 2. The trachea and bronchi are similar in morphology.

Their lumens are lined by pseudostratified columnar ciliated epithelium with goblet cells (respiratory epithelium), underlain by a connective tissue lamina propria and a deeper connective tissue submucosa with coiled sero-mucous glands that open onto the surface lining of the airway lumen. Click slide 1. Deep to the submucosa are the hyaline cartilage rings that add structure to the wall of the airway and prevent its collapse. Peripheral to the cartilage is a connective tissue adventitia. The sero-mucous glands are also visible in this slide. Click slide 3.

The bronchioles, in contrast, are much smaller in diameter with a continuous layer of smooth muscle in place of the cartilaginous reinforcements. A gradual decrease in the height of the epithelium to simple columnar also occurs as the bronchioles decrease in diameter. Distally the bronchioles give way to the respiratory bronchioles, alveolar ducts, alveolar sacs, and alveoli in which gas exchange occurs. In the respiratory bronchiole, the epithelium becomes simple cuboidal and the continuous smooth muscle layer is interrupted at intervals by the presence of alveoli inserted into the bronchiolar wall.

Click slide 4. Although some exchange occurs in the respiratory bronchiole, it is within the alveoli of the alveolar ducts and sacs that the preponderance of gas exchange transpires. Here the walls of the alveoli, devoid of smooth muscle, are reduced in thickness to the thinnest possible juxtaposition of simple squamous alveolar cell to simple squamous capillary endothelial cell. What are the primary functions of the respiratory epithelium? What is the primary functional unit of the lung? alveoli The alveolar wall is very delicate and subject to collapse.

Why is there no smooth muscle present in its wall for support? smooth muscle would hinder the gas exchange What are the three basic components of the air-blood barrier? alveolar, capillary walls and basal laminae humidfy, filter and warm incoming air Why doesn’t gas exchange occur in bronchi? bronchi have no alveoli Histology Review Supplement 129 Digestive Tissue Review From the PhysioEx main menu, select Histology Review Supplement. When the screen comes up, click Select an Image Group. From Group Listing, click Digestive Tissue Slides.

To view slides without labels, click the Labels Off button at the bottom right of the monitor. smooth muscle nearest the stomach, and a mix of both skeletal and smooth muscle in between. 4. The outermost layer of the esophagus is an adventitia for the portion of the esophagus in the thorax, and a serosa after the esophagus penetrates the diaphragm and enters the abdominal cavity. Click slide 3. Here we can see the abrupt change in epithelium at the gastroesophageal junction, where the esophagus becomes continuous with the stomach. Briefly explain the difference between an adventitia and a serosa. Salivary Gland

The digestive process begins in the mouth with the physical breakdown of food by mastication. At the same time salivary gland secretions moisten the food and begin to hydrolyze carbohydrates. The saliva that enters the mouth is a mix of serous secretions and mucus (mucin) produced by the three major pairs of salivary glands. Click slide 1. The secretory units of the salivary tissue shown here are composed predominantly of clusters of pale-staining mucussecreting cells. More darkly stained serous cells cluster to form a demilune (half moon) adjacent to the lumen and contribute a clear fluid to the salivary secretion.

Salivary secretions flow to the mouth from the respective glands through a well-developed duct system. Are salivary glands endocrine or exocrine glands? serosa secret serous fluid, and adventitia don’t. Stomach The wall of the stomach has the same basic four-layered organization as that of the esophagus. Click slide 4. The mucosa of the stomach consists of a simple columnar epithelium, a thin connective tissue lamina propria, and a thin muscularis mucosa. The most significant feature of the stomach mucosa is that the epithelium invaginates deeply into the lamina propria to form superficial gastric pits and deeper gastric glands.

Although the epithelium of the stomach is composed of a variety of cell types, each with a unique and important function, only three are mentioned here (see slide 5). Click slide 5. The surface mucous cells are simple columnar cells that line the gastric pits and secrete mucus continuously onto the surface of the epithelium. The large round pink- to red-stained parietal cells that secrete hydrochloric acid (HCl) line the upper half of the gastric glands; more abundant in the lower half of the gastric glands are the chief cells (not shown), usually stained blue, that secrete pepsinogen (a precursor to pepsin).

Click slide 4. The submucosa is similar to that of the esophagus but without glands. The muscularis externa has the two typical circumferential and longitudinal layers of smooth muscle, plus an extra layer of smooth muscle oriented obliquely. The stomach’s outermost layer is a serosa. What is the function of the mucus secreted by surface mucous cells? exocrine Which salivary secretion, mucous or serous, is more thin and watery in consistency? serous Esophagus

Through contractions of its muscular wall (peristalsis), the esophagus propels food from the mouth to the stomach. Four major layers are apparent when the wall of the esophagus is cut in transverse section: Click slide 2. 1. The mucosa adjacent to the lumen consists of a nonkeratinized stratified squamous epithelium, its immediately subjacent connective tissue (lamina propria) containing blood vessels, nerves, lymphatic vessels, and cells of the immune system, and a thin smooth muscle layer (muscularis mucosa) forms the boundary between the mucosa and the submucosa.

Because this slide is a low magnification view, it is not possible to discern all parts of the mucosa nor the boundary between it and the submucosa. 2. The submucosa is a layer of connective tissue of variable density, traversed by larger caliber vessels and nerves, that houses the mucus-secreting esophageal glands whose secretions protect the epithelium and further lubricate the passing food bolus. 3. Much of the substance of the esophageal wall consists of both circumferentially and longitudinally oriented layers of muscle called the muscularis externa.

The muscularis externa is composed of skeletal muscle nearest the mouth, 130 Histology Review Supplement protects the epithelium Small Intestine The key to understanding the histology of the small intestine lies in knowing that its major function is absorption. To that end, its absorptive surface area has been amplified greatly in the following ways: 1. The mucosa and submucosa are thrown into permanent folds (plicae circulares). 2. Fingerlike extensions of the lamina propria form villi (singular: villus) that protrude into the intestinal lumen (click slide 7). 3.

The individual simple columnar epithelial cells (enterocytes) that cover the villi have microvilli (a brush border), tiny projections of apical plasma membrane to increase their absorptive surface area (click slide 6). Click slide 7. Although all three segments of the small intestine (duodenum, jejunum, and ileum) possess villi and tubular crypts of Lieberkuhn that project deep into the mucosa between villi, some unique features are present in particular segments. For example, large mucous glands (duodenal glands, Brunner’s glands) are present in the submucosa of the duodenum.

In addition, permanent aggregates of lymphatic tissue (Peyer’s patches) are a unique characteristic of the ileum (click slide 8). Aside from these specific features and the fact that the height of the villi vary from quite tall in the duodenum to fairly short in the terminal ileum, the overall morphology of mucosa, submucosa, muscularis externa, and serosa is quite similar in all three segments. Why is it important for the duodenum to add large quantities of mucus (from the duodenal glands) to the partially digested food entering it from the stomach?

Click slide 10. Located in the surrounding connective tissue, roughly at the points of the hexagon where three lobules meet, is the portal triad (portal canal). Click slide 12. The three constituents of the portal triad include a branch of the hepatic artery, a branch of the hepatic portal vein, and a bile duct. Both the hepatic artery and portal vein empty their oxygen-rich blood and nutrient-rich blood, respectively, into the sinusoids. This blood mixes in the sinusoids and flows centrally in between and around the hepatocytes toward the central vein.

Bile, produced by hepatocytes, is secreted into very small channels (bile canaliculi) and flows peripherally (away from the central vein) to the bile duct. Thus, the flow of blood is from peripheral to central in a hepatic lobule, while the bile flow is from central to peripheral. What general type of cell is the phagocytic Kupffer cell? immune Blood in the portal vein flows directly from what organs? liver What is the function of bile in the digestive process? protects intestinal walls raises alkalinity to create ideal pH Colon Click slide 9.

The four-layered organization is maintained in the wall of the colon, but the colon has no villi, only crypts of Lieberkuhn. Simple columnar epithelial cells (enterocytes with microvilli) are present to absorb water from the digested food mass, and the numbers of mucous goblet cells are increased substantially, especially toward the distal end of the colon. Why is it important to have an abundance of mucous goblet cells in the colon? because they secrete mucous, which is important to fascilitate degestion Pancreas Click slide 13. The exocrine portion of the pancreas synthesizes and secretes pancreatic enzymes.

The individual exocrine secretory unit, or acinus, is formed by a group of pyramidal-shaped pancreatic acinar cells clustered around a central lumen into which they secrete their products. A system of pancreatic ducts then transports the enzymes to the duodenum where they are added to the lumen contents to further aid digestion. The groups of pale-staining cells are the endocrine pancreatic islet (islets of Langerhans) cells. Liver The functional tissue of the liver is organized into hexagonally shaped cylindrical lobules, each delineated by connective tissue.

Click slide 11. Within the lobule, large rounded hepatocytes form linear cords that radiate peripherally from the center of the lobule at the central vein to the surrounding connective tissue. Blood sinusoids lined by simple squamous endothelial cells and darkly stained phagocytic Kupffer cells are interposed between cords of hepatocytes in the same radiating pattern. Histology Review Supplement 131 Renal Tissue Review From the PhysioEx main menu, select Histology Review Supplement. When the screen comes up, click Select an Image Group.

From Group Listing, click Renal Tissue Slides. To view slides without labels, click the Labels Off button at the bottom right of the monitor. The many functions of the kidney include filtration, absorption, and secretion. The kidney filters the blood of metabolic wastes, water, and electrolytes and reabsorbs most of the water and sodium ions filtered to regulate and maintain the body’s fluid volume and electrolyte balance. The kidney also plays an endocrine role in secreting compounds that increase blood pressure and stimulate red blood cell production.

The uriniferous tubule is the functional unit of the kidney. It consists of two components: the nephron to filter and the collecting tubules and ducts to carry away the filtrate. Click slide 1. The nephron itself consists of the renal corpuscle, an intimate association of the glomerular capillaries (glomerulus) with the cup-shaped Bowman’s capsule, and a single elongated renal tubule consisting of segments regionally and sequentially named the proximal convoluted tubule (PCT), the descending and ascending segments of the loop of Henle, and the distal convoluted tubule (DCT).

Click slide 2. A closer look at the renal corpuscle shows both the simple squamous epithelium of the outer layer (parietal layer) of the glomerular capsule (Bowman’s capsule) and the specialized inner layer (visceral layer) of podocytes that extend footlike processes to completely envelop the capillaries of the renal glomerulus. Processes of adjacent podocytes interdigitate with one another, leaving only small slits (filtration slits) between the processes through which fluid from the blood is filtered.

The filtrate then flows into the urinary space that is directly continuous with the first segment of the renal tubule, the PCT. The PCT is lined by robust cuboidal cells equipped with microvilli to greatly increase the surface area of the side of the cell facing the lumen. Click slide 3. In the loop of Henle, lining cells are simple squamous to simple cuboidal. The DCT cells are also simple cuboidal but are usually much smaller than those of the PCT. The sparse distribution of microvilli, if present at all, on the cells of the DCT relates to their lesser role in absorption.

The DCT is continuous directly with the collecting tubules and collecting ducts that drain the filtrate out of the kidney. The large renal artery and its many subdivisions provide an abundant blood supply to the kidney. The smallest distal branches of the renal artery become the afferent arterioles that directly supply the capillaries of the glomerulus. In a unique situation, blood from the glomerular capillaries passes into the efferent arteriole rather than into a venule.

The efferent arteriole then perfuses two more capillary beds, the peritubular capillary bed and vasa recta that provide nutrient blood to the kidney tissue itself, before ultimately draining into the renal venous system. In which segment of the renal tubule does roughly 75–80% of reabsorption occur? proximal convoluted tubules How are proximal convoluted tubule (PCT) cells similar to enterocytes of the small intestine? both absorb water, salts, vitamins, phosphates

Starting from inside the glomerular capillary through to the urinary space, what are the three layers through which the filtrate must pass? glomerular capillary enothelium, glomrular basement membrane visceral layer of bowman’s capsule Under normal circumstances in a healthy individual, would red blood cells or any other cells be present in the renal filtrate? no In addition to providing nutrients to the kidney tubules, what is one other function of the capillaries in the peritubular capillary bed? they deliver blood to tubular sites 132 Histology Review Supplement