BIOLOGY 590: PHYSIOLOGY OF HUMAN SYSTEMS

MIDTERM III (Final Exam) EXAMPLE

Use Scantron form ParSCORE to tell me your selection for the best answer on the multiple choice section in Part A (Note: there are 35 multiple choice questions.  Answer essay questions in Part B directly on the test.


Part A: (70 points total) Mark the Scantron form for the letter that represents the one best answer. Each multiple choice question is worth 2 Points.

1. Generally, to be maximally activated, protein kinase C must:

     a. bind diacylglycerol and IP3

b. bind diacylglycerol

c. translocate to the plasma membrane

d. bind to raf or ras

e. bind PLC and diacylglycerol

2. The tubular transport maximum of a substance is:
1. maximal transport rate of a substance that is secreted by the nephron

2. maximal transport rate of a substance that is reabsorbed and/or secreted by the nephron

3. maximal transport rate of a substance that is reabsorbed by the nephron

4. the plasma level of the substance at which it first begins to appear in the urine

5. the minimual plasma level of the substance that can be measured

6. the plasma level of the substance above which no endocrine response is elicited

  a. all of the above

  b. 1

  c. 2

  d. 4

  e. 1, 2 & 3


 
 
3.Which of the following statement(s) is/are true about Ras and Raf?
         Ras                                                  Raf

1. is activated by GTP binding                     phosphorylates MAPKK

2. is a monomeric GTP-binding protein           couples to adenylate cyclase

3. couples to adenylate cyclase                 is a monomeric GTP-binding protein

4. is activated by GTP binding                         binds to a subunits

5. is activated by a GNRP                   becomes membrane bound when activated

  a. 1 & 2

  b. 2 & 3

  c. 3 & 5

  d. 4 & 5

  e. 1 & 5

4. The activation of Raf typically
a. depends on Ras and is facilitated by GNRPs

b. is mediated by the a subunit of G-proteins

c. depends on GAP (GTPase activating protein)

d. is dependent on DAG formation and Ca release

e. is the direct result of fos and jun activation

5. Peptide hormones are         because         , steroid hormones are         because         , and neurotransmitters are         because 
a. stored in granules; they are small; not stored in cells; they are hydrophillic; stored in granules; small

b. stored in granules; they are hyrophobic; not stored in cells; they are hydrophillic; stored in granules;     hydrophillic

c. not stored in granules; they are hyrophillic; not stored in cells; they are lipophillic; stored in granules; hydrophillic

d. stored in granules; they are hyrophillic; not stored in cells; they are hydrophobic; stored in granules; small

e. stored in granules; they are hyrophillic; not stored in cells; they are lipophillic; stored in granules; hydrophillic

6. If a substance possess a clearance of 25 ml/min, a urine level of 50 mg/ml and the urine flow rate is 2 ml/min, then what is the plasma level of the substance?
a. 1 mg/ml

b. 0.25 ml/min

c. 0.25 mg/ml

d. 4 mg/ml

e. 4 ml/min

7. If the filtered load of the substance discussed in question 6 is 480 mg/min, then the GFR is
a. 120 mg/ml

b. 480 mg/ml

c. 100 ml/min

d. 480 ml/min

e. 120 ml/min

8. Adenylate cyclase _________, while phospholipase C __________.
a. is stimulated by Gs and uses ATP; is stimulated directly by Gq and uses PIP2 as a substrate

b. is activated by raf; forms DAG and IP3 and is activated by Ras

c. stimulates PKC and is coupled to Ca channels; stimulates CaMK and is coupled to Raf activation.

d. is stimulated by Gs; is stimulated by Gq and uses IP3 as a substrate

e. is typically coupled to G-protein activation; is typically coupled to Ras activation

9. If the GFR is 100 ml/min, when the plasma levels of a substance are 5 mg/ml, the substance has an excretion rate of 100 mg/min, however, when the plasma levels of the substance is 15 mg/ml, it has an excretion rate of 1100 mg/min. It is probable that this substance is:
a. reabsorbed and has a Tm of about 400 mg/min

b. reabsorbed and has a Tm of about 100 mg/min

c. reabsorbed and has a Tm of about 750 mg/min

d. secreted and has a Tm of about 750 mg/min

e. secreted and has a Tm of about 400 mg/min

10. The main function of the salt gradient in the renal medulla is to:
a. to differentiate water and salt reabsorption by the ascending vs descending Loop of Henle

b. serve as the driving force for diuresis by facilitating water reabsorption by the distal collecting duct

c. serve as the driving force for water reabsorption by the distal collecting duct

d. remove medullary salt by the vasa recta

e. remove medullary water by the vasa recta

11. The reabsorption of glucose takes place at the ___ through the action of a ____ that also transports ______.
a. proximal tubule; symporter; chloride

b. proximal tubule; antiporter; sodium

c. proximal tubule; antiporter; chloride

d. proximal tubule; symporter; sodium

e. proximal tubule; antiporter; HC03

12. Decreases in blood pressure are detected by _______. This causes a/an ___________, a/an ________________, and a/an _________________.
a. baroreceptors; increase vasopressin release; decrease sympathetic NS activity; decrease renin release

b. baroreceptors; increase vasopressin release; increase sympathetic NS activity; increase renin secretion

c. osmoreceptors; decrease vasopressin release; decrease sympathetic NS activity; decrease in renin release

d. baroreceptors; decrease vasopressin release; increase sympathetic NS activity; increase renin secretion

e. osmoreceptors; increase vasopressin release; increase sympathetic NS activity; increase angiotensinogen

13. Which of the following is not true about renal water reabsorption?
1. most of it occurs at proximal tubule cells where aquaporins are required

2. most of it occurs at proximal tubule cells where most Na is also reabsorbed

3. some takes place in descending Loop of Henle but it is required for countercurrent exchange

4. little takes place in collecting ducts but here it is regulated by angiotensin II

   a. 1

   b. 1 & 4

   c. 3 & 4

   d. 1 & 2

   e. 1 & 3

14. Which of the following is not true about glomerular filtration rate?
a. it is equal to the clearance rate for substances that are freely filtered

b. it is relatively unchanged over normal increases in blood pressure

c. it can average up to 180 l/day

d. it can be measured with inulin or creatinine

e. none of the above

15. Hypothalamic diabetes insipidus can be due to __________________, while nephrogenic diabetes insipidus can be due to ___________________.
a. diminished ADH production; mutations in the aquaporin protein

b. hypothalamic production of insulin; toxins generated in the kidney

c. overproduction of ADH; mutations in aquaporins

d. overproduction of hypothalamic releasing factors; overproduction of renin

e. mutations in the aquaporin protein; mutations in the ADH protein

16. Aldosterone is produced when ______________. It acts at the ______________ by ______________ the activity of ___________________ which results in _______________ sodium excretion.
a. blood volume is low; loop of Henle; increasing; Na/K ATPase; decreased

b. blood volume is high; proximal tubule; increasing; Na/K ATPase; decreased

c. blood volume is high; collecting duct; decreasing; Na/K ATPase; increased

d. blood volume is high; collecting duct; increasing; Na/K ATPase; increased

e. blood volume is low; collecting duct; increasing; Na/K ATPase; decreased

17. In the most of the obligate Na, Cl and H2O is linked to a located on the cells.
a. distal collecting duct; reabsorption; Na/K ATPase; basolateral membrane

b. distal collecting duct; reabsorption; N/H symporter; basolateral membrane

c. proximal tubule; reabsorption; Na/H symporter; basolateral membrane

d. proximal tubule; reabsorption; Na/K ATPase; basolateral membrane

e. proximal tubule; reabsorption; Na/K ATPase; apical membrane

18. When circulating volume is increased stretch receptors in the __________ cause the release of ___________, while _________________ causes the _______________ release of _________________.
a. hypothalamus; ADH; aortic stretch; increased; renin

b. aorta; epinephrine; decreased sympathetic NS activity; decreased; atrial natriuretic peptide

c. aorta; renin; decreased sympathetic NS activity; decreased; atrial natriuretic peptide

d. atria; atrial natriuretic peptide; increased angiotensin II; increased; aldosterone

e. atria; atrial natriuretic peptide; decreased angiotensin II; decreased; aldosterone

19. You evaluate a patient presenting with the following symptoms and lab results: Inappropriately high urine volume (approx. 10 L/day), extremely high ADH levels, high renin and angiotensin II, low atrial natriuretic peptide levels. You make the diagnosis as:
a. nephrogenic diabetes mellitus

b. hypothalamic diabetes mellitus

c. nephrogenic diabetes insipidus

d. diabetes mellitus

e. Addison's disease

20. Metabolic acidosis is characterized by _____________ due to _______________, while metabolic alkalosis is characterized by _____________ due to _______________.
a. low plasma pH; inadequate H secretion by kidneys; high plasma pH; too much non-volatile base

b. high plasma pH; too much H secretion by kidneys; low plasma pH; too little non-volatile base

c. low plasma pH; too much H secretion by kidneys; high plasma pH; too little non-volatile base

d. high plasma pH; inadequate H secretion by kidneys; low plasma pH; too much non-volatile base

e. low plasma pH; inadequate HC03 secretion by kidneys; high plasma pH; too much H in urine

21. Which of the following is not true for any lipophillic hormone?
a. translocates to the nucleus when ligand binds

b. always bound to specific hormone response elements

c. bind hsp90 in the cytoplasm

d. are synthesized partly in the smooth endoplasmic reticulum

e. none of the above

22. You evaluate a patient presenting the following symptoms: weight loss, increased heart rate, increased food intake. The following lab values are available: increased 131I uptake, low TSH, high T3/T4. You make the diagnosis as:
a. hyperthyroidism due to insufficient TSH

b. hyperthyroidism due to insufficient TRH

c. hyperthyroidism due to insufficient dietary iodide

d. hyperthyroidism due to Grave's disease

e. hyperthyroidism due to Cushing's syndrome

23. Which of the following is not true about throid hormone?
a. T3 is more potent than T4

b. is originally produced as part of thyroglobulin

c. binds to receptors located on DNA

d. released in direct response to TRH

e. is acted upon by peroxidase during its biosynthesis

24. Under normal conditions in humans feedback regulation of biosynthesis is regulated primarily by .
a. thyroid stimulating hormone; thyroglobulin

b. adrenocorticotropic hormone; cortisol

c. antidiuretic hormone; aldosterone

d. follicle stimulating hormone; corticosterone

e. adrenocorticotropic hormone; corticosterone

25. You evaluate a patient presenting the following symptoms: loss of appetite, muscle weakness, weight loss. The following lab values are available: decreased plasma cortisol, increased ACTH, neither metyrapone or CRH challenge alter plasma cortisol. You make the diagnosis as:
a. pituitary adenoma (ACTH secreting)

b. corticotrope insufficiency

c. adenocarcinoma

d. adrenal hyperplasia

e. adrenal insufficiency

26. An individual with an XY chromosome pair is found to have testes, no internal sexual organs, and the external genetalia of a male. This is most likey the result of which of the following:
a. non-functional DHT receptors

b. non-functional testosterone receptors

c. lack of testes determination factor production

d. non-functional antimullerian hormone

e. overproduction of estrogen

27. LH is produced by __________ and it regulates ___________ and __________, while FSH, which is produced by __________________, regulates _____________ and ______________.
a. gonadotropes; testosterone synthesis; estradiol synthesis; gonadotropes; Graffian follicle growth; spermatogenesis

b. luteotropes; testosterone synthesis; estradiol synthesis; gonadotropes; Graffian follicle growth; spermatogenesis

c. gonadotropes; testosterone synthesis; estradiol synthesis; gonadotropes; Leydig cell growth; spermatogenesis

d. gonadotropes; testosterone synthesis; cortisol synthesis; gonadotropes; Graffian follicle growth; spermatogenesis

e. luteotropes; testosterone synthesis; estradiol synthesis; follitropes; Graffian follicle growth; spermatogenesis

28. In a normal male the proper development of the internal reproductive organs depends on
a. Mullerian hormone secretion

b. Wolffian duct development and dihydrotestosterone

c. Mullerian duct development

d. Anti-mullerian hormone

e. Wolffian duct development and testosterone

29. Which of the following is not true about the role of androgens and androgen receptors in males?
a. DHT is produced from testosterone by 5-a-reductase

b. DHT deficiency causes feminization of the internal genetalia

c. 5-a-reductase deficiency can cause feminization of the external genetalia

d. testosterone is produced by the testes while DHT is not

e. DHT acts at steroid receptors in the brain

30. Which of the following is not true about the endocrine regulation of ovulation?
a. progesterone is high only during the luteal phase

b. an LH surge triggers ovulation

c. granule cells are a major source of estradiol

d. FSH is lower than LH during most of the follicular growth phase

e. estradiol always serves as a negative modulator of LH production

31. The addition of cholesterol to the sperm plasma membrane
a. takes place during capacitation

b. takes place in the male reproductive tract

c. a key step in the final stage of fertilization

d. is impaired in persons taking Ca channel blockers

e. is required for "recognition" of the zona pellucida by sperm

32. Capacitation
a. can be activated by Ca channel blockers

b. occurs in the epididymus and involves Ca influx

c. occurs in the female reproductive tract and requires Ca influx

d. involves cholesterol uptake by the sperm plasma membrane

e. is impaired in men taking b-blockers

33. is a cardiac derived hormone that is released from the heart by and causes , while is a synthesized in the & controls water reabsorption in .
a. Atrial natriuretic factor; increased plasma volume; increased sodium excretion; antidiuretic hormone; neurohormone; hypothalamus; the adrenal gland

b. Atrial natriuretic factor; decreased plasma volume; increased sodium excretion; antidiuretic hormone; neurohormone; hypothalamus; collecting duct cells

c. Adrenalin; high blood pressure; vasoconstriction; adrenal corticotropic hormone; pituitary; adrenals

d. Adrenal cortical hormone; increased atrial stretch; increased water excretion; antidiuretic hormone; neurohormone; hypothalamus; collecting duct cells

e. Atrial natriuretic factor; increased plasma volume; increased sodium excretion; antidiuretic hormone; neurohormone; hypothalamus; collecting duct cells

34. Many present-day female contraceptive drugs mimic by supplying which function(s) primarily by which usually .
a. the corpus luteum; progestrone & estrogen; blocking FSH/LH release; prevents ovulation

b. the developing follicle; progestrone & estrogen; blocking FSH/LH release; prevents ovulation

c. the corpus luteum; estrogen; blocking FSH/LH release; prevents ovulation

d. false luteal phase; estradiol; blocking FSH; prevents ovulation

e. the proliferative phase; estradiol & progesterone; blocking FSH/LH release; prevents ovulation

35. The filtration fraction amounts to _________ of the plasma entering the glomerulus.
a. 20%

b. 0.20%

c. about half

d. 75%

e. 100%

PART B: (80 points total).

1. (18 points) In the pituitary the        cells of the          lobe produce the hormone          which activates the production of          by adrenal fasciculata cells. However, in the          of the adrenal gland,          is the major hormone produced which also serves as a neurotransmitter in the          nervous system.

In a patients suffering from hyperproduction of cortisol, metyrapone as a diagnostic tool. If metyrapone causes increased 11-deoxycortisol, then the problem could be with the (name a gland)          which may be under producting; over producing (circle one) the hormone           .

In the pituitary the           lobe is responsible for storing the hormone           which acts on receptors on           cells to increase the activity of           signal transduction system which ultimately causes vasoconstriction. This same hormone can also act on           receptors on           cells to increase the activity of           signal transduction system. 

2. (6 points) Diagram the endocrine loops of the hypothalamic/pituitary/thyroid axis naming each tissue and hormone clearly.

Click here to link to the answer for Essay Question 2

3. (10 points) Diagram the cellular pathways by which thyroxine (thyroid hormone) is produced.

Click here to link to the answer for Essay Question 3

4. (10 points) Diagram the molecular pathway by which Site A on the thyroglobulin molecule is converted to T4. 

Click here to link to the answer for Essay Question 4