Microsoft Word - midterm #2 2019 shortened
BIO 3302 Animal Physiology II - Midterm #2
KM Gilmour NAME: _________________________________
November 25th, 2019
80 min STUDENT #: ____________________________
Cellular phones, unauthorized electronic devices or course notes (unless an open-book exam) are
not allowed during this exam. Phones and devices must be turned off and put away in your bag.
Do not keep them in your possession, such as in your pockets. If caught with such a device or
document, the following may occur: academic fraud allegations will be filed which may result in
you obtaining a 0 (zero) for the exam.
By signing below, you acknowledge that you have ensured that you are complying with the above
statement.
SIGNATURE: _________________________________
Part A: Answer the following questions in the space provided on the question sheet. (1 mark per
answer unless otherwise stated; 24 marks in total)
1. The hyperventilation experienced by a human at high altitude is stimulated by a fall in blood PO2
that is detected by type I (glomus) cells located in the carotid body. It results in an acid-base
distu
ance best described as a respiratory OR metabolic (select one) acidosis OR alkalosis (select
one).
2. Compensation for a metabolic acidosis is a challenge to ionic homeostasis in a marine teleost such
as the clownfish because…
a. Sea water is more highly buffered than fresh water, reducing the effectiveness of the acid-
trapping mechanism.
. Fish cannot afford to hypoventilate because O2 uptake would be compromised.
c. Acid excretion in exchange for Na+ uptake by gill ionocytes adds to the salt load the fish must
excrete.
d. Marine teleost fish lack a rectal gland to excrete excess NaCl.
e. All of the above explain why compensation for a metabolic acidosis is a challenge to ionic
homeostasis in a marine teleost.
2
4. The cell in the figure at right illustrates a suite of structural
characteristics that is often found in cells specialised fo
the function of
_______________________________________.
a. Identify two of these structural characteristics and in
each case explain its functional significance. (2
marks)
. Assume that this cell was found in the salt-secreting gland of the Galapagos marine iguana, and
add to the diagram above the three key mem
ane proteins expected to be found in a salt-
secreting cell. (3 marks)
5. The figure at right presents the main inorganic and
organic solutes in the extracellular fluids of three water-
eathing verte
ates.
Which bar (A, B or C) represents an osmoconformer that
ionoregulates? ____________
The animal represented by which bar (A, B or C) would
experience water loss to the su
ounding environment?
____________
O
sm
ol
a
ity
(m
O
sm
ol
L-
1 )
0
200
400
600
800
1000
1200 Na+
Cl-
Other cations
Other anions
urea
methylamines
sea
wa
ter A B C
3
7. The sketch at right illustrates the pressures that drive
glomerular filtration.
a. Calculate the hydrostatic pressure gradient (show you
calculation):
. Which pressure is controlled by autoregulatory
mechanisms? ___________
8. Xenopus (the African clawed frog) is an exception to the rule that adult amphibians are
ammonotelic OR ureotelic OR uricotelic (select one) because it remains fully aquatic as an adult
and therefore excretes ammonia OR urea OR uric acid (select one).
9. The sketch at right illustrates a mammalian nephron
and nephrons found in teleost fish from marine and
freshwater environments.
a. Explain the functional significance of the
structural difference between nephrons B and C.
(2 marks)
. Explain the functional significance of the structural difference between nephrons A and D. (2
marks)
4
Part B: Answer the following questions in the exam booklet. (19 marks in total)
1. List two structural adaptations for life in a desert that are displayed by the kangaroo rat, and explain
(BRIEFLY) the functional significance of each. (4 marks)
2. A group of (fictional) BIO 3302 students decided to investigate the effects of several solutions on
kidney function. Urine flow rate (UFR), urine pH and urine osmotic concentration were measured
following consumption of 500 mL of water, 2% NaCl, lemonade or beer. The data collected 1 h
after consumption of the test solution are presented below together with “control” data for a student
that drank water only when thirsty. Which student drank 500 mL of water, and what is the main
hormonal response responsible for adjusting kidney function in this student? Please explain your
easoning. (5 marks)
Name UFR
(mL h-1 kg-1)
Urine pH
(pH units)
Urine osmotic
concentration
(mmol kg-1)
Opah Winfrey XXXXXXXXXX
Brad Pike XXXXXXXXXX
Angelfish Jolie XXXXXXXXXX
Carpi B XXXXXXXXXX
Control XXXXXXXXXX
Microsoft Word - midterm #2 2017
BIO 3302 Animal Physiology II - Midterm #2
NAME: _________________________________ November 23rd, 2017
80 min
STUDENT #: ____________________________
Cellular phones, unauthorized electronic devices or course notes (unless an open-book exam) are
not allowed during this exam. Phones and devices must be turned off and put away in your bag.
Do not keep them in your possession, such as in your pockets. If caught with such a device or
document, the following may occur: academic fraud allegations will be filed which may result in
you obtaining a 0 (zero) for the exam.
By signing below, you acknowledge that you have ensured that you are complying with the above
statement.
SIGNATURE: _________________________________
Part A: Answer the following questions in the space provided on the question sheet. (1 mark per
answer unless otherwise stated; 23 marks in total)
1. Minor fluctuations in filtrate flow are detected by the ____________________________________
which signals to the ______________________________________________ to release vasoactive
compounds that act on the afferent arteriole to adjust glomerular blood pressure and hence
filtration.
2. The Magadi tilapia is an unusual teleost fish because…
a. It retains ammonia as the end-product of nitrogen metabolism even when it emerges from
water.
. It is a facultative ureotele that excretes urea across the gill in discrete pulses that occur about
once in every 24-h period.
c. It is an obligate ureotele that cannot excrete ammonia because of the high pH of the water in
which it lives.
d. It accumulates high levels of urea and the counter-balancing solute TMAO as an
osmoregulatory strategy to prevent water loss in its marine environment.
e. It excretes uric acid.
3. An increase in which of the following will decrease urinary Na+ loss?
a. Circulating angiotensinogen levels
. Circulating aldosterone levels
c. Circulating ADH levels
d. Circulating atrial natriuretic peptide (ANP) levels
e. Increases in all of the above cause urinary Na+ loss to decrease
2
5. Mammals are more resistant to water loss than amphibians. List two structural features that
contribute to this difference, and
iefly explain their significance. (4 marks)
6. Active NaCl excretion by the ________________________________________________ of the
Galapagos marine iguana is an example of a regulated OR obligatory (select one) exchange.
7. On the axes at right, sketch the relationship
etween body fluid osmolarity and the osmolarity
of the external environment for the
ine shrimp,
Artemia. (1 mark)
In seawater, this animal is best described as a
(select one) euryhaline OR stenohaline (select
one) hyperosmotic OR iso-osmotic OR hypo-
osmotic (select one) regulator OR conformer. Bo
dy
fl
ui
ds
o
sm
ol
a
ity
(m
O
sm
ol
L-
1 )
0
XXXXXXXXXX
Environmental osmolarity (mOsmol L-1)
0
1500
1000
500
Iso-osmotic
line
3
9. True OR false (select one): Exposure of rainbow trout to hyperoxic (high O2) water causes a
espiratory alkalosis.
a. Justify your answer.
. The activity of what cell type in the gill would increase to co
ect the acid-base distu
ance?
10. You drink three large pints of beer in rapid succession. Which one of the following best describes
the renal response that will occur?
a. No change in urine flow rate or osmolarity.
. Decreased production of urine; the urine is more concentrated than normal.
c. Increased production of dilute urine.
d. Decreased production of urine; the urine is highly acidic.
e. Increased production of urine of normal osmolarity.
Which one of the following best describes the hormonal response to beer consumption; this
hormonal response results in the above renal response?
a. Increased ADH levels in conjunction with a fall in aldosterone levels.
. The concentration of atrial natriuretic peptide (ANP) increased.
c. No change in any of ADH, aldosterone or ANP levels.
d. The ADH concentration fell.
e. Increased ADH levels in conjunction with an increase in angiotensin II levels.
4
Part B: Answer the following questions in the exam booklet. (20 marks in total)
1. Sam the sockeye salmon spent his first year of life in a freshwater stream. He is now ready to
move into the ocean but must first go through ‘smoltification’, the physiological transition from a
freshwater teleost to a marine teleost. Explain the physiological changes that occur, using you
knowledge of the ionoregulatory and osmoregulatory challenges faced by teleost fish in freshwate
versus marine environments and the strategies they use to overcome these challenges. (8 marks)
2. Structure and function are often intimately linked in physiological systems, i.e. structures may be
uniquely adapted to ca
y out particular functions, or the function of a particular system is made
possible by its structure. Discuss such structure-function relationships with respect to the filtration
mechanism of the verte
ate kidney. (6 marks)