DIRECTIONS

1.     Please PRINT your name on each page of examination immediately!!!!  NOW!!
2.     Answer the questions using a pen if you wish the right to a re-grade request.
3.     You absolutely must confine your answers to the spaces provided.  Do not
        wander off onto the back of a page, the margins around some other question, or
        such foolishness.
4.     Your handwriting (printing) must be legible.
5.     TEAR OFF THE LAST (DATA) PAGE OF THE EXAM.
6.     If you have completed the examination before the end of the 50 minute period,
        sign the honor statement below, and place the exam in the correct envelope at the
        front of the room.  If you use all of the allotted 50 minutes, please remain seated
        until all examinations have been collected.

  
I certify that I neither sought, received, nor gave any unauthorized information while taking this examination.

_____________________________________ ________________
Signature                                                                        Date

 Prove it three ways with numerical data:

1.________________________________________________________________

2.________________________________________________________________

3.________________________________________________________________

 How much of this substance is secreted/min? ________________________
 

e. How much of substance L appears in the urine/minute?	____________________
f. How much of substance K appears in the filtrate/minute?	____________________
g. Which substance is reabsorbed?	____________________
How much is reabsorbed/min?	____________________
h. What is the subject’s cardiac output?	____________________
i. What is the subject’s alveolar ventilation rate?	____________________
j. What is the E of inulin in this subject?	____________________
k. What is the clearance of inulin in this subject?	____________________
l. What % of plasma substance L appears in the filtrate in     Bowman’s Capsule?	____________________
m. How much water is reabsorbed/min?	____________________

#2.     Partial occlusion of the renal artery induces pronounced hypertension within a few days.  Please LIST the steps (a LIST, if you please!) beginning with the occlusion that lead to this hypertension:  (19 points)
 
 
 
 
 
 
 
 
 
 
 

#3.     In the lab you induce hypovolemic shock in your laboratory rat.   In an effort to then save the rat, your lab partner (who missed far too many Mam Phys lectures) suggests administering normal isotonic (300 mosm saline = 0.9%) saline. You however suggest that the rat would be better able to recover if you administer saline that included some high molecular weight Dextran molecules. Why is your plan more likely to save the animal? (22)
 
 
 
 
 
 
 
 
 
 
 
 

#4.     Use the following data to answer the following questions.  (Units, please!!!)
Total lung capacity = 5000 ml;                  Inspiratory reserve volume = 1500 ml;
Expiratory reserve volume = 2300 ml;      Residual volume = 600 ml;
Ventilation rate = 20 breaths/ min

a. Calculate tidal volume (7 pts)
       _________________________

b. You conduct an experiment in which you fill all of the conducting structures (ONLY Conducting structures!!) with 250 ml of colored vapor. Calculate alveolar (minute) ventilation. (8 pts)

       __________________________

#5.     In yet another freak laboratory accident, you manage to inject a substantial amount of sodium phosphate (an excellent plasma buffer) into your anesthetized lab rat. Very quickly you notice that the rat’s rate and depth of respiration decrease. Outline the steps of the homeostatic mechanism responsible for this response (remember to include specifically what initiates it ). (22)
 
 
 
 
 
 
 
 
 
 
 
 
 

#6.     On the following axis, draw the following oxy-hemoglobin dissociation curves and label them with the following letters.

    A.   --->   Curve with a p50 of 65 mm Hg. (6 points)
    B.   --->    Curve for same hemoglobin after  plasma pCO₂ has increased significantly. (6 points)

 
Explain why you positioned curve “B” as you did, that is why did the curve shift? (10 points)
 
 
 
 
 
 
 
 
 
 

#7. Now let's finish up with some INCREASE ( I  ), DECREASE ( D ), or NO CHANGE (No ) questions:  (2 pts each)
 

a. As GFR decreases below normal,  TPR will soon	a__________
b. As efferent arteriole diameter decreases, GFR	b__________
c. As renal sodium reabsorption increases, urine volume	c__________
d. As someone breathes through a garden hose, A pool (DRG) activity	d__________
e. As plasma POxygen increases, the amount of hemoglobin carbamino compounds	e__________
f. As vagal nerve stimulation increases, C pool (VRG) activity	f__________
g. As filtrate passes through the PCT, the filtrate concentration of inulin	g__________
h. As alveolar ventilation rate decreases, plasma pH	h__________
i. If lactic acid is injected, peripheral chemoreceptor AP firing immediately	i__________
j. As afferent arteriole diameter decreases, GFR	j__________
k. As plasma aldosterone levels increase, tubular potassium secretion	k__________
l. As renal blood flow decreases, afferent arteriole diameter	l__________
m. At the onset of expiration, transpulmonary pressure	m__________
n. As Bowman's capsule hydrostatic pressure increases, GFR	n__________
o. As fluid flows through the PCT, tubular fluid inulin concentration	o__________
p. As fluid flows through the PCT, tubular sodium content	p__________
q. As fluid flows through the DCT, tubular fluid potassium levels	q__________
r. As plasma CO2 levels increase, [Cl-] within plasma (outside of rbc’s)	r__________
s. As plasma glucose levels increase above 200mg/100 mls, tubular glucose reabsorption	s__________
t. As plasma glucose levels increase above 200 mg/100mls, renal glucose filtration	t__________
u. As plasma levels of PAH increase, Bowman's capsule filtrate levels of PAH	u__________
v. As plasma levels of PAH increase, urine PAH levels	v__________
w. As O2 levels in surrounding interstial fluid increase, pulmonary arteriole diameter	w__________
x. As lung surfactant decreases, lung compliance	x__________
y. During left ventricular failure, net filtration across pulmonary capillaries	y__________
z. When O2 levels the expired air increase, bronchiole diameter	z__________
aa. If venous reserve increases, hemoglobin p50	aa__________
ab. At the intial onset of inspiration, alveolar pressure	ab__________
ac.  As someone breathes through a garden hose, A pool DRG) activity	ac__________
ad. As arterial pO2 decreases to 75 mm Hg, O2 receptor AP firing	ad__________
ae. During exercise, TPR	ae__________

 
DATA PAGE: Tear off this page and use it for calculations and creative  doodling.

Dr. Harley Schmedlap, Jr., noted physiologist and EMT worker who specializes in reviving comatose students at MCAT test sites, gathered the following data from one of the recent test takers.  You will notice that these individuals can no longer be considered “normal” human subjects, so you may not make any assumptions about the FF or the Clearance of Inulin.  Schmedlap injected 50mg of each of 4 substances, K, L, M and V,  i.v. before gathering the following data.  Substance V did not appear in glomerular filtrate or renal tubular fluid; the other substances did appear there.
 

Substance	PA (mg/100 ml plasma)	PV (mg/100 ml plasma)	U (mg/ml)
K	2.0	1.0	3.0
L	2.0	0.5	4.5
M	2.0	1.8	0.6
V	2.0	2.0	0

Rate of urine formation =  0.8 ml/min

FF = 0.22                            Hematocrit = 0.45

HR = 70 beats/min              End Systolic Vol = 40 ml              End Diastolic Vol = 90 ml

Respiratory Rate = 12 breaths/min                                      Tidal volume = 196 ml/breath

Volume of conducting respiratory structures (dead space) = 46 ml