NEM 10V Lecture Notes - Lecture 41: Peripheral Nervous System, Homeostasis, Epithelium

The human body is truly remarkable and is designed tofunction effectively. Organs are important structures composed ofdifferent tissues that facilitate specific functions within thebody. Organs function as part of an integrated group of structuresknown as organ systems. These organ systems form the organizationalunits that are responsible for crucial processes necessary forsustaining life.

Examples of organ systems include but are not limitedto the cardiovascular system, the digestive system, themusculoskeletal system, the nervous system, the excretory system,the endocrine system and the respiratory system. Even organ systemsdo not function alone. These systems work together, interactingwith other organs in a functional network that keeps the body inbalance. (Look up the term homeostasis in your text.) When homeostasis orthe normal functioning of organ systems is disrupted, disease maydevelop causing injury to the body, or even death. In thisassignment, you will explore organ systems, as well as associateddiseases or malfunctions.

Assignment details:

Take a look at the following casestudies that detail an outcome associated with a disease/organmalfunction. Select onestudy to investigate further for yourassignment.

Critically evaluate the information provided andcorrelate it with the organ systems that are affected in thescenario. Use the information that you have gathered to answer theassignment questions that follow the case study. For assistancewith your assignment, please use your text, the AIU Library, Webresources, and course materials.

Case Study 1:

Atherosclerosis isnarrowing of arteries caused by the accumulation of fatty depositson the arterial walls.

On June 22, 2002 the St. Louis Cardinals werepreparing for their upcoming baseball game against the Chicagocubs. Concern arose when their prized pitcher, 33-year old DarrylKile did not show up for practice. Soon after, he was found stillin his hotel room where he had suddenly died in his sleep (New YorkTimes, 2002). It was discovered that the cause of death was relatedto three of his coronary arteries being 80-90% blocked as a resultof atherosclerosis (New York Times, 2002), which ultimately causedhim to undergo a heart attack.

Answer the following assignmentquestions:

1. Why would atherosclerosis result in a heart attack?Provide a brief explanation based on how the heart functions.
2. How are arteries different from veins andcapillaries? Describe the functions of both arteries andveins.
3. Vertebrates and some invertebrates have a closedcirculatory system. Explain the advantage of having a closedcirculatory system over an open circulatory system?
4. Briefly explain how the lymphatic system isassociated with the circulatory system?
5. Describe one disease that affects the lymphaticvessels similarly to the way that atherosclerosis affects thearteries?

Case Study 2:

Cigarette smoking remainsthe leading preventable cause of death in the United States,causing an estimated 438,000 deaths - or about 1 out of every 5 -each year (National Cancer Institute, 2008).

Mr. Amos is now 57 years old and has been smoking forthe past 30 years of his life. A recent doctor's visit reveals thatMr. Amos has stage 3 lung cancer, characterized by his symptoms ofnagging chest pain, fatigue, coughing up blood, substantial weightloss, and increased carbon dioxide levels in his blood. The doctorinformed Mr. Amos that had he quit his smoking habit several yearsago, he would have reduced his risk for developing lung cancerlater in life. Mr. Amos immediately begins treatment for the lungcancer that has metastasized to his lymph nodes.

Answer the following assignmentquestions:

1. What main components in cigarettes affect therespiratory system? Explain their effects on specific organs, cellsand/or processes in the respiratory system.
2. There are alternate mechanisms of transportingcarbon dioxide (CO2) and oxygen (O2 ) in the blood. Explain howsmoking might lead to increased levels of carbon dioxide in theblood.
3. Can smoking affect other organ systems of the body?Give specific examples and briefly explain your answer.
4. How can you correlate cellular respiration with therespiratory system?
5. Does smokeless tobacco present a reduced risk forlung cancer and other smoking associated diseases? Provide evidencefor your answer.

Case Study 3:

Gigantism is abnormallylarge growth during childhood caused by excess growth hormonesecreted by the anterior pituitary gland.

Robert Wadlow, born on February 22, 1918, weighed anormal eight pounds, six ounces. However, by the time Robertreached the age of six months old, he weighed 30 pounds (Hamilton,1993). Within only a year, his weight rose to 62 pounds, more thandouble the normal weight of a baby at 18 months. Aside from hisweight, Robert continued to grow at an astounding rate, reachingsix feet, two inches and 195 pounds by the time he was eight yearsold. Robert's unique size was attributed to an over activepituitary gland, which produced much higher than normal levels ofgrowth hormone. At the time of his death in July 1940 at the age of22, Robert had reached a height of 8 feet 11.1 inches and weighed485 pounds (Hamilton, 1993).

Answer the following assignmentquestions:

1. How does growth hormone regulate various bodyfunctions in adults, and what could cause the excess secretion ofgrowth hormone?
2. Discuss the relationship between growth hormone andinsulin, and are there complications associated with theirinteraction?
3. Why is gigantism usually more difficult to treatthan dwarfism?
4. Give examples of two other hormones secreted by thepituitary, and briefly describe how they specifically affect otherorgan systems of the body?
5. Some athletes have resorted to the illegal use ofanabolic steroids to increase strength and muscle size. How areanabolic steroids different from growth hormone? Briefly explainyour answer.

References

1. Kidneys help to maintain a proper balance of _________ within the body.

Phosphorous

Chloride

Potassium

Calcium Phosphate

ions

All of the above

2. The nervous system has how many major categories?

3

2

13

4

3. Which major category of the nervous system contains both the Somatic and the Autonomic divisions?

Central Nervous System

Peripheral Nervous System

Neither of these

Both of these

4. Which organ or structure helps to control the master endocrine gland (pituitary gland)?

The pancreas

The thorax

Peyer’s patches

The hypothalamus

6. This tiny gland is located at the base of the brain and produces the hormone melanin.

Parathyroid

Pituitary

Hypothalamus

Pineal

7. These glands are situated right above the kidneys. The hormones produced by these glands help us to cope with stress.

Thyroid

Parathyroid

Hypothalamus

Adrenals

8. The hormones necessary for the production of sperm are produced in the __________.

Kidneys

Testes

Ovaries

None of the above

9. The bloodstream assists the endocrine organs and structures by:

Removing hormones from the body

Delivering hormones to target cells

Delivering hormones to secretory cells

The bloodstream does not come into contact with endocrine structures or organs
10. The pancreas _____________.

Is a master gland that controls many other glands

Produces progesterone and oestrogen

Is a salivary gland

Regulates blood sugar, aid in digestion

11. The basic function of the endocrine system is ________ in nature.

Digestive

Reproductive

Hormonal

Proximal

13. Urinary tract infections (UTIs) are experienced by many people during their lifetimes. Urinary tract infections can involve any bacterial infection of the urinary system structures; the kidneys, bladder, ureters, or urethra. They are caused by bacteria entering the body through the urethra and traveling upward into the body. Symptoms can range from mild discomfort when urinating to extreme pain and the loss of blood during urination. They occur more frequently in women than men, and are often treated by antibiotics in addition to home remedies, such as drinking more water and drinking cranberry juice.

Based on what you have learned about the cause of urinary tract infections, which of the following precautions would help to prevent reoccurring infections?

Taking pain medication when symptoms occur

Placing a hot pack on the abdomen when symptoms occur

Practicing good hygiene Exercising regularly

14. The nervous system is divided into two major divisions: the Central Nervous System and the Peripheral Nervous System. Those divisions have structures that can be classified as belonging to two different subdivisions: the Somatic and the Autonomic systems. The nervous system can be summarized as a complex system of interconnected nerves and special cells called neurons that are used to transmit information (by means of small electrical impulses). Use the information in the table below to help answer questions about the nervous system. Division Organs & Structures Functions Central Nervous System (CNS) Brain Spinal Cord Nerves This is the body’s assessment and communication center. It analyzes the information received from the sensory neurons and responds. Peripheral Nervous System (PNS) Sensory Neurons Ganglia (clusters of neurons) Nerves that connect to one another and to the CNS The sensory neurons react to physical stimuli such as light, sound, heat, and pressure, and transmit that information to the CNS. Subdivisions Description Examples Somatic The Somatic system is comprised of nerves that connect the brain and spinal cord to the muscles of the body and sensory receptors in the skin. Reactions to physical stimuli like heat or light. Using your hand to touch Eating food Autonomic The Autonomic system largely involuntary. This system controls the unconscious functions of the body. Breathing Blood Pressure

Feeling overwhelmed or startled by exposure to very loud noises is likely a reaction to information collected by which subdivision of the nervous system:

Somatic

Autonomic

No answer text provided.

No answer text provided.

15. The thyroid gland is perhaps the most well-known member of the pancreatic system. Many adults are screened for thyroid problems during routine physical exams. This butterfly shaped gland is found at the base of the neck and releases hormones that affect the body’s metabolism (the way the body uses energy). The thyroid’s two main hormones are T3 and T4, and they affect many body functions, including: • Breathing • Heart rate • Central and peripheral nervous systems • Body weight • Muscle strength • Menstrual cycles • Body temperature • Cholesterol levels Two common disorders associated with the thyroid include hyperthyroidism and hypothyroidism. Some of the symptoms associated with these disorders are listed in the table below. Hyperthyroidism (Too many hormones released) Hypothyroidism (Too few hormones released) Anxiety Irritability or moodiness Nervousness, hyperactivity Sweating or sensitivity to high temperatures Hand trembling (shaking) Hair loss Missed or light menstrual periods Trouble sleeping Tiredness and fatigue Difficulty concentrating Dry skin and hair Depression Sensitivity to cold temperature Frequent, heavy periods Joint and muscle pain A patient complains of arthritis-like pain in the joints of her hands, but tests for arthritis come back negative. The doctor then suggests a thyroid function test. The doctor is most likely concerned about:

High levels of T3 and T4 hormones in the body

Low levels of T3 and T4 hormones in the body

No answer text provided.

No answer text provided

Matt and Maria have now received and begun to eat their Chinese takeout. They have accomplished biting off a portion of a piece of their General Tso's chicken and rice and proceeded to chew and swallow. For this report, you will describe the path the chicken and rice follows and the physiological processing that take place to convert the chicken and rice into their nutritional components that can be used by the body for energy and homeostatic processes. Consider the following as you proceed through your research and discussion of this topic.

1.Through which organs, and in what order does the bolus of food travel?

2. How long does the food remain in each segment of the digestive tract and what physiological processing takes place during this time?

3. What role does the autonomic nervous system play in controlling the movement of food through the digestive tract? What other physical or physiological factors can impact the movement of food though the digestive tract?

4. What specific enzyme or other digestive substances are associated with each segment of the digestive tract and which cells produce these substances? What specific components of the chicken and rice (proteins, carbohydrates, etc.) are processed by each of these substances?

5. What role do the accessory digestive organs play in the process? What are the specific cells of each of these accessory organs and what substances do they produce? Where in the digestive tract are the substances introduced into the digestive process?

6.What is the ultimate fate of the digested chicken and rice? What was the initial biological structure of the nutritional components first consumed (example proteins breaking down to their simpler components) and what are the resulting products resulting from digestion that are now ready and available for use by the body for energy and homeostasis?

7. What is the fate of the solid and fluid components that are not absorbed into the body? When and where does control of movement of digestive tract content transition from the autonomic nervous system controlled smooth muscles to peripheral nervous system control of voluntary skeletal muscles?