LIFE SCIENCES 2018
CLASS TEST 2
UNIT 2: EXCRETION
SURNAME:__________MEMO____________________ STUDENT NR. ___________________
Question 1 [10]
Choose the alternative that best completes the statement or answers the question. Only encircle the
correct letter.
1.1 A marine sea star was mistakenly placed in freshwater and it died. What is the most likely
explanation for its death?
A) The sea star was stressed and needed more time to acclimate to new conditions.
B) The sea star is hyperosmotic to the freshwater, and it could not osmoregulate .
C) The osmoregulatory system of the sea star could not handle the change in ionic
content presented by the freshwater.
D) The contractile vacuoles used to regulate water content ruptured in the freshwater.
E) The cells of the sea star dehydrated and lost the ability to metabolize.
1.2 Which feature of osmoregulation is found in both marine and freshwater bony fish?
A) loss of water through the gills.
B) gain of salt through the gills.
C) loss of water in the urine.
D) no drinking of water.
E) gain of water through food.
1.3 Where and from what compound(s) is urea produced?
A) Liver from NH3 and CO2.
B) Liver from glycogen.
C) Kidneys from glucose.
D) Kidneys from glycerol and fatty acids.
E) Bladder from uric acid and H2O.
1 | Page
, LIFE SCIENCES 2018
1.4 What is the main nitrogenous waste excreted by birds?
A) ammonia
B) nitrate
C) nitrite
D) urea
E) uric acid
1.5 Which of the following nitrogenous wastes requires hardly any water for its excretion?
A) amino acid
B) urea
C) uric acid
D) ammonia
E) nitrogen gas
1.6 Which group possess excretory structures known as nephridia?
A) flatworms
B) earthworms
C) insects
D) vertebrates
E) cnidarians
1.7 The transfer of fluid from the glomerulus to Bowman's capsule
A) results from active transport.
B) transfers large molecules as easily as small ones.
C) is very selective as to which subprotein sized molecules are transferred.
D) is mainly a consequence of blood pressure in the capillaries of the glomerulus
E) usually includes the transfer of red blood cells to the Bowman's capsule.
1.8 Which of the following would contain blood in a normally functioning nephron?
A) vasa recta
B) Bowman's capsule
2 | Page
CLASS TEST 2
UNIT 2: EXCRETION
SURNAME:__________MEMO____________________ STUDENT NR. ___________________
Question 1 [10]
Choose the alternative that best completes the statement or answers the question. Only encircle the
correct letter.
1.1 A marine sea star was mistakenly placed in freshwater and it died. What is the most likely
explanation for its death?
A) The sea star was stressed and needed more time to acclimate to new conditions.
B) The sea star is hyperosmotic to the freshwater, and it could not osmoregulate .
C) The osmoregulatory system of the sea star could not handle the change in ionic
content presented by the freshwater.
D) The contractile vacuoles used to regulate water content ruptured in the freshwater.
E) The cells of the sea star dehydrated and lost the ability to metabolize.
1.2 Which feature of osmoregulation is found in both marine and freshwater bony fish?
A) loss of water through the gills.
B) gain of salt through the gills.
C) loss of water in the urine.
D) no drinking of water.
E) gain of water through food.
1.3 Where and from what compound(s) is urea produced?
A) Liver from NH3 and CO2.
B) Liver from glycogen.
C) Kidneys from glucose.
D) Kidneys from glycerol and fatty acids.
E) Bladder from uric acid and H2O.
1 | Page
, LIFE SCIENCES 2018
1.4 What is the main nitrogenous waste excreted by birds?
A) ammonia
B) nitrate
C) nitrite
D) urea
E) uric acid
1.5 Which of the following nitrogenous wastes requires hardly any water for its excretion?
A) amino acid
B) urea
C) uric acid
D) ammonia
E) nitrogen gas
1.6 Which group possess excretory structures known as nephridia?
A) flatworms
B) earthworms
C) insects
D) vertebrates
E) cnidarians
1.7 The transfer of fluid from the glomerulus to Bowman's capsule
A) results from active transport.
B) transfers large molecules as easily as small ones.
C) is very selective as to which subprotein sized molecules are transferred.
D) is mainly a consequence of blood pressure in the capillaries of the glomerulus
E) usually includes the transfer of red blood cells to the Bowman's capsule.
1.8 Which of the following would contain blood in a normally functioning nephron?
A) vasa recta
B) Bowman's capsule
2 | Page
