Please answer all questions.

6. If tropomyosin is never moved off actin, what would be the result?

7. If you died, why would you develop rigor mortis?

8. All of the motor units in the fingers were very large (many muscle fibers per motor unit. How would this affect function?

9. If the calcium (Ca++) pumps did not function how would this affect muscles?

Going Under the Knife: A Case on Membrane Structure and Function

Twenty-year-old Kevin groaned and clutched his abdomen as he lay on the emergency room gurney. He had just been diagnosed with acute appendicitis and was waiting to be taken to the operating room (OR). Although he desperately wanted the pain to stop, Kevin was terrified of having general anesthesia. He hoped his fear wasn’t obvious to his older brother Cole, who was finishing medical school and thought he knew everything.

“Hang in there,” Cole said, for what seemed like the eighteenth time. “I’m sure they’ll get you upstairs as soon as they can. They don’t want that thing to burst.”

Kevin grunted. “I know…but does that anesthesia staff work all the time? How can I not wake up when someone’s slicing my gut open?”

Cole assumed a professorial air, and Kevin wished he’d kept his mouth shut. However, Cole didn’t get a chance to say anything before an aide arrived to take Kevin to the OR.

In the OR, someone placed a mask over Kevin’s face and when he blinked, he suddenly found himself in a hospital room with Cole waiting in a chair by the bed. “Welcome back to consciousness, little brother. How’s your abdomen feel?”

Kevin frowned. “Not as bad as it did. So it’s over? How did I get here already?”

“You’ve been out for a few hours,” Cole chuckled and then launched into the wonders of general anesthesia. “Certain neurons have to depolarize and undergo an action potential to maintain consciousness, but some anesthetics can hyperpolarize them and produce unconsciousness. The anesthetic binds to and opens a certain kind of potassium channel, which increases the “leak” current of potassium. However, it doesn’t affect voltage-gated potassium channels. This inhibits the neurons, and therefore you aren’t conscious of the surgeons performing the procedure. Amazing!”

Kevin groaned again, but not from the pain this time. Cole was undoubtedly right but he sounded like a textbook. “I’m just glad the stuff worked. Now when can I go home?”

Short answer questions

1. Kevin is conscious when certain neurons in his brain are active—they depolarize and undergo action potentials. Describe the process of depolarization of a neuron to threshold.

2. What does Cole mean when he says that anesthesia “inhibits the neurons?”

3. If the anesthesia opens more potassium leak channels, why are Kevin’s neurons less likely to produce action potentials?

4. Suppose Kevin’s pre-op blood work indicates that his extracellular potassium concentration is much higher than usual. This condition is known as hyperkalemia and must be corrected before he can undergo surgery. One of the dangers of hyperkalemia is that it makes neurons and muscle cells more excitable. Why does elevated extracellular potassium have this effect?

Case Study – Atherosclorosis Francois was shoveling some light snow off of the driveway when he suddenly experienced a severe chest pain. He felt a weight on his chest and was having trouble breathing. A stab of pain also radiated across the left side of his neck and down his left arm. His wife called 911 and an ambulance picked him up and brought him to the local hospital. The resident told him that he was suffering from angina pectoris. As he lay there resting, the pain subsided and he began paying attention as the doctor asked him some questions and did a few basic measurements. He was 52 years old, 5’10” tall and weighed 210 lbs. His girth at the waist was 42 inches. An MRI of his neck revealed artherosclerotic plaque buildup in his carotid arteries. He told the doctor that he smoked about 3 packs of cigarettes per week, did not drink alcohol and had a relatively sedentary lifestyle. They took a blood sample and did a variety of tests.

The results follow: Low density lipoprotein was 210mg/dl

Triglycerides were 195mg/dl

High density lipoprotein was 28mg/dl

Creatine kinase was elevated The doctor set him home the next day with a prescription for a statin drug and instructions to get regular, moderate exercise and carefully monitor his diet. He was told to try to get his BMI down to 25 and his girth to 36”.

2. What is Francois’ BMI? What does the combination of BMI and waist girth tell you about his risk factors for cardiovascular disease?

3. What do the LDL, triglyceride and HDL measurements tell you about his risk factors? What other risk factors does he have?

4. What does the elevated CPK mean? How did this enzyme get into his plasma?

5. What are statins and how do they work?

Hypertension

1. Define and describe the pathology fully.

Hypertension

1. What is the treatment?

2. What is the prognosis?

Describe the general cellular components, structures, fibers, and matrix (where applicable) of each type of connective tissue.

1. One of the variables on the computer output from the exercise test is RQ, which stands for respiratory quotient, or RER, which stands for respiratory exchange ratio.
   How is RQ or RER determined? What is the difference between these two terms? How would you expect RER to change during a long-duration bike ride?

QUESTION ONE: A patient experiencing shortness of breath due to reduced oxygen carrying capacity of the blood would benefit most from:

(A)Whole blood donation (B) Red Blood Cell donation (C)Sterile intravenous fluid administration (D)Plasma donation

QUESTION TWO: Erythrocytes:

(A) Quickly repair damage to themselves or to vessel walls (B) Produce EPO is response to low oxygen levels

(C) Are composed mainly of intracellular gas transport proteins (D)Require oxygen for cellular metabolism

QUESTION THREE:During the life (or death) of erythrocytes:

(A)RBC's live in the blood for 20-40 days (B)Developing RBC's contain nuclei and ribosomes (C) Hemocytoblasts in the kidneys give rise to most RBC's (D)Following hemolysis, bilirubin is recycled for new RBC's

QUESTION FOUR: Which of the following is most likely in individuals with kidney failure?

(A)Low hematocrit (B)Leukopenia (low leukocyte count) (C) Thrombocytopenia (low platelet count) (D) Low amount of clotting factors

QUESTION FIVE:

Donated plasma is often separated into its many useful components. What plasma component would be useful in immunodeficient individuals without antibodies?

(A)Globulins (B)Albumins (C) Formed Elements (D)Hemoglobin

After identifying the conducting and respiratory zones, discuss the differences between internal and external respiration in terms of location, and forces that trigger them.

how do I write my case study for assignment work ? should I wrote in paraphrase format or answered to every question sequentially.plz, give me an answer with example..thanks in advance.

Compare the shuttle systems for transporting fatty acids into the mitochondria and acetyl-CoA into the cytosol.

Describe the differences between peroxisomal and mitochondrial β oxidation.

Describe the various ways by which cholesterol synthesis is regulated.