WAEC Biology 2017 Question 13

Question 13

Excretion

The diagram below is an illustration of the urinary tubule in a mammal. Which of the following substances is found in the part labelled II only?

A.Lipid
B.Protein
C.Salts
D.Water

Show the answer and explanation

Answer: B (Protein)

Explanation

Part II is the blood vessel bringing blood to the glomerulus. Plasma proteins are too large to be filtered, so they stay in the blood and are not found in the tubule.