Past paper questions to learn

Question 1

What effect does fertiliser have

Answer 1

-More nitrate available for uptake by crop plant
-More nitrogen for protein synthesis

Question 2

Why are bats a good resevoir

Answer 2

-similar physiology to humans
-social animals resulting in large contact with humans
-fly large ranges and potentially in contact with other organisms

Question 3

What is the importance of reverse transcriptase in retroviruses

Answer 3

reverse transcriptase allows conversion of (single stranded) RNA into
(double stranded) DNA;
allowing incorporation into host genome

Question 4

How does a substance which interacts with the active site of acetylcholinesterase affect the post synpatic neurone

Answer 4

Blocking the active site of the enzyme and prevents formation of the
enzyme-substrate complex;
so acetylcholine remains bound to receptor and neurone cannot
repolarise;

Question 5

How does a longer loop of henle function to conserve water

Answer 5

The loop of henle creates a high salt concentration in the medulla. The longer the loop of henle, the more water is reabsorbed from the collecting duct into the blood (vasa recta system). It allows for more concentrated urine to be produced. Necessary to conserve water/ prevent dehydration