Write one to two paragraphs describing the role of insulin in the metabolism of glucose, fat, and protein. Also, discuss how insulin is related to the manifestations of diabetes.

1. List and describe possible harmful effects of a severe blow to the head.

2. Describe the two types of shunt procedures used to treat hydrocephalus, distinguishing between them with respect to the site of drainage from the shunt.

3. List and briefly describe the methods available to detect a neural tube defect in a fetus.

Name three histological features that exist to increase the absorptive function of digestive tissues.

John and Thomas are in an automobile accident and are brought to the emergency room, both with head trauma. John seems to have sustained injuries to his temporal lobe while Thomas has an injury in the lower brainstem region including his medulla oblongata. Which patient would be likely to have an injury that is life-threatening? Why?

1. Trace a sperm from formation to fertilization. Name all of the structures through which it passes. Include all additional structures that contribute to semen volume. Identify the products each produces.  
   
2. Once fertilized, describe all of the steps and sub-steps discussed in the lectures, from zygote to delivery. Include the physiological changes that occur and the hormones that are involved.  
   
3. Explain Incomplete Dominance and give an example.   

A) If the thickness of the chest is 20 cm, what percentage of X-rays are transmitted through the chest at a certain incident X-ray energy assuming HVL values of 3.5 and 1.8 cm for muscle and bone, respectively, and the bone thickness to be 4 cm and muscle thickness 16 cm.

B) If CT images are acquired at the same X-ray energy as above, calculate the CT numbers for muscle and bone voxels assuming the linear attenuation coefficient of water is 0.1 cm-1

1. The NKCC2 transporter is blocked by ____ as a treatment ____

   1. Loop diuretics ; to reduce Na+ reabsorption

   2. ACE inhibitors; to reduce fluid excretion XX

   3. Thiazides; to reduce fluid retention

   4. K sparing diuretics; for hypertension

2. Which of the following would be a result of treatment with an ACE-I drug?

   1. Decreased production of Renin

   2. Decreased production of angiotensinogen

   3. Decreased fluid volume in the circulatory system,

   4. All of the above

Case Study – Acute Renal Failure She was found behind an overturned table after the bomb blast destroyed the sidewalk coffee shop. She had several large wounds and had lost quite a bit of blood. She was also burned over about 10% of her body surface. At the scene, rescuers stopped the major blood loss and evacuated her, but they were not able to rouse her and it was several hours until she could be delivered to the hospital. Her heart rate was 120 bpm and her blood pressure was 60/42. She was immediately given intravenous fluids while her wounds were being tended to. After she was treated in the emergency room she was kept in the hospital for further evaluation. By this time her pulse was 90 bpm and her blood pressure was 75/60. She was only producing 20 ml of urine per hour and her blood work revealed high BUN (blood urea nitrogen), creatinine and potassium concentrations. A creatinine clearance test indicated that her GFR was 26 ml/minute. They decided that she was suffering from prerenal acute renal failure, caused by the extreme hypovolemia from her hemorrhage and burns. The treatment was intravenous administration of isotonic solutions containing glucose and bicarbonate, the fluid to replace lost blood volume and the bicarbonate to lower serum potassium concentrations. Because of concerns about the hyperkalemia, her electrocardiogram was closely monitored for any increases in the size and shape of the T-wave. After her fluids had been adequately managed, her renal function did not fully return to normal right away. She was showing some indications of acute tubular necrosis. After a few weeks of careful monitoring of her hydration and electrolyte concentrations her renal function returned to normal.

1. Why was her heart rate so high and blood pressure so low when she was first discovered?

2. What was the cause of the decreased GFR and urine volume?

3. What was the cause of the elevated BUN, creatinine and serum potassium?

4. Why would hyperkalemia be expected to cause dangerous changes in her ECG?

5. Why would bicarbonate administration help the hyperkalemia?

6. Why did prerenal acute renal failure progress to acute tubular necrosis?

Case Study – Diabetes Mellitus Mohinder, a 28 year old male, had been diagnosed with diabetes mellitus when he was 12 years old. He started experiencing polydipsia, polyuria and polyphagia and his parents noticed that he was very lethargic and seemed continuously fatigued. They would occasionally detect the sweet, “fruity” smell of acetone on his breath. Their PA informed them that this was a sign of ketoacidosis associated with the diabetes. At the time, high fasting glucose levels and islet cell antibodies (ICA) had been detected in his blood. His doctors had him carry out a regimen to control his fluctuations in blood glucose which included diet, exercise and administration of exogenous insulin. At first he was administering insulin 1-3 times a day as indicated by measuring the glucose concentrations in small blood samples obtained from pricking his finger. When he was 22, he got a small battery-powered infusion pump that continuously infused insulin subcutaneously. Now he is considering an experimental treatment that involves implantation of beta-cells derived from donated pancreases. These cells implant in the liver and produce insulin in response to blood glucose levels.

3. What do the ICA suggest about the etiology of his condition?

4. Why is an insulin infusion pump superior to periodic insulin injections? Why would donated beta-cells be superior to the infusion pump if they can be successfully implanted? (Think about the negative feedback loops for control of blood glucose as you answer this question. How do the concepts of sensitivity, gain and lag time relate to this question?)

5. What are the drawbacks to donated pancreas cells? How might embryonic stem cells be used to avoid these problems?

Electrocardiogram Lab (ECG)

This Exercise is done using the Ph.I.L.S CD  

Do the lab #22. ECG and Exercise.Or just click here to there

Look at your data and compare each time interval for the resting and post-exercise state.

1. Are any of the time intervals approximately constant?
2. With the exception of the R-R interval, which time interval shows the greatest difference between resting and post-exercise? Explain this observation.
3. If the coronary arteries fill when the heart muscle is relaxed, what happens to the time course of coronary blood flow when the heart rate is increased?
4. What happens to the amount of work done by the heart as the heart rate is increased?

Would this explain why most heart attacks (periods when there is insufficient blood flow to parts of the heart) take place during physical exertion?

1. How are the left and right hippocampi different?
2. Why are optogenetics and chemogenetics important for understanding the functioning of the nervous system?
3. How might the findings that the left and right hippocampus are different inform studies of human conditions, such as Alzheimer’s Disease?