13). Describe the structural & functional differences between a myofilament & a myofibril?

14). List four (4) proteins found in the myofilaments & describe their physical arrangement with respect to each other.

15). Describe the overlapping pattern of thick & thin myofilaments & explain how this overlap pattern accounts for the A band, I band, H band & Z disc appearances.

16). What differences would you expect to see between a motor unit where muscular strength is more important than fine control & another motor unit where fine control is more important than muscular strength?

Describe the effects of FSH, LH, estrogen & progesterone on the initiation & maintenance of a normal human 28-day menstrual (ovarian) cycle in which fertilization does not occur.

distinguish structurally and functionally between primordial follicles, primary follicles, secondary follicles and a mature follicle.

Describe the effects of FSH, LH, estrogen & progesterone on the initiation & maintenance of a normal human 28-day menstrual (ovarian) cycle in which fertilization does not occur.

Distinguish structurally & functionally between primordial follicles, primary follicles, secondary follicles & a mature follicle

What, if anything, is apparently abnormal in the urine of this patient?

Normally, the procedure for urinalysis dip sticks involves dipping the strip in the sample of urine for 5– 10 seconds and then removing. Wait approximately one minute, then compare any color changes with the rubric provided. Specific pH is also often performed since tests strips for pH are limited.

Note: Quantitative analyses are not being performed. Evaluation of the results should simply identify whether the value is below normal, normal, or above normal.

The following question regards action potentials and neurons:

1.) A.) How is the physiology different for an excitatory synapse vs. an inhibitory synapse? Consider neurotransmitter differences, ion channel differences, and how they affect the potential of the post synaptic cell

B.) (3 points) How is an electrical gradient produced across a gradient? How is this related to having a membrane potential?

C.) (4 points) A) Describe negative feedback in physiology. B) How is negative feedback important for maintaining homeostasis?

D.) (4 points) Under what circumstances would cells produce lactate? If a cell produces and can’t use lactate, what happens to it?

E.) (3 points) Can an action potential be initiated when the membrane is experiencing the relative refractory period? Explain the physiology of why or why not.

What factor(s) can create positive feedback, making shock following hemorrhage get worse instead of better? Choose all that apply.

NATIONAL CENTER FOR CASE STUDY TEACHING IN SCIENCE

Take a Deep Breath:
A Case of Respiratory Illness

by

Brianna S. Nelson, Kelsey N. Aguirre, Alee L. Adams, Emily E. Brodbeck, and Breanna N. Harris Department of Biological Sciences
Texas Tech University, Lubbock, TX

Part I – Symptoms

Callie was 26 years old when she opened a bakery called “Callie’s Cupcakes” in downtown San Francisco with her fiancé, Jeremy. Despite the competitive market, her business was booming; everyone loved the clever recipes and the trendy atmosphere. Between running their fast-growing business and planning for their wedding, Callie hadn’t been able to keep to her usual eight hours of sleep a night. Although she had always lived a very healthy lifestyle, exercising daily and eating healthy, she just hadn’t been feeling herself lately. She was tired all the time, had difficulty breathing, felt stressed, coughed up sputum, consistently ran a low-grade fever, and had lost weight as her appetite decreased. None of these symptoms alone had been particularly alarming so she had put off seeing her physician for a few weeks.

Questions

1. What are Callie’s symptoms? List all that were mentioned.

2. Based on the symptoms presented, what are three possible respiratory infectious diseases Callie could be suffering from? Explain why.

3. Based on Callie’s symptoms and your answers so far, it seems Callie is having trouble with her respiratory system. Several respiratory conditions can impact gas exchange. Describe the process of gas exchange in the lung (alveoli).

Discuss the methodological factors which can impact the quality of EMG data and how could this be minimised or eliminated?

(Total 8 marks)

A new drug called Xaelenfal is on the market. Xaelenfal is an AMPA receptor antagonist, meaning that it binds onto AMPA receptors without activating them and prevents glutamate from binding.

i. If I take the drug Xaelenfal, how will this effect EPSPs recorded in the postsynaptic neuron when an excitatory presynaptic neuron fires an action potential? (1 point)

ii. How will the drug Xaelenfal effect IPSPs in the postsynaptic neuron when an inhibitory presynaptic neuron fires an action potential? (1 point)

iii. In a normal brain, synapses can get stronger when a presynaptic cell repeatedly causes a postsynaptic cell to depolarize (we call this long-term potentiation, or LTP). Explain how long term potentiation works including the following details. (3 points)
- Name the neurotransmitter that is released by the presynaptic cell.
- Name the receptor that this neurotransmitter binds to on the postsynaptic cell to mediate normal excitatory transmission.
- What other receptors are involved and how do they get recruited?
- List one way in which the presynaptic neuron changes and one way in which the postsynaptic neuron changes during LTP.

iv. Given what you know about plasticity, could Xaelenfal effect the ability of synapses to potentiate. Explain your answer. (2 points)

What type of hormone is aldosterone? What receptors does aldosterone utilize? What is the mechanism of action of aldosterone?

Use an example to explain the classic endocrine cell-to-cell signaling pathway

The two major categories of hormone receptors are (1) receptors which catecholamines can utilize and (2) receptors which thyroid hormones can utilize.

1.?

2.?

Positive feedback mechanisms are used to maintain homeostasis. Describe the positive feedback regulation, the contractions of labor, and answer the questions below in great detail. (8 pts)

For positive feedback:

What is the variable? (0.5 pt)

What is the normal range? (0.5 pt)

Which conditions may change the variable? (0.5 pt)

How the changes to be detected? (1 pt)

What is/are the response(s)? (1 pt)

What is the final effect? (0.5 pt)