Section II

Questions 13 - 16

Question 13
The lines J-K and M-L in the following diagram are parallel. Find the length of MN (give your answer as a fraction).

Question 14
The diagram shows some of the bones and muscles of the ankle joint.

What changes take place when someone with their feet flat on the ground starts to go on tiptoe?

A gastrocnemius muscle contracts, ankle joint extends

B gastrocnemius muscle contracts, ankle joint flexes

C gastrocnemius muscle relaxes, ankle joint extends

D gastrocnemius muscle relaxes, ankle joint flexes

Question 15
The following equation represents the reversible reaction, responsible for the formation of ammonia (NH₃).

N_{2 (g)} + 3H_{2 (g)} <--> 2NH_{3 (g)}

An increase in pressure in this system will result in which one of the following?

A a decrease in the rate of reaction

B an increase in the amount of N2

C an increase in the amount of ammonia

D an increase in the amount of H2

E none of the above

Question 16
The diagrams show two blood vessels in cross-section. Both diagrams are at a magnification of x 20.

How does vessel X differ from vessel Y?

A Has valves, carries blood away from the heart.

B Has valves, carries blood towards the heart.

C Has no valves, carries blood away from the heart.

D Has no valves, carries blood towards the heart.

Answers for questions 13-16