questions that have shown up in an aqa exam that i didnt get

Question 1

biopsychology

why can neurons only go one direction?

3 marks

Answer 1

the neurons are released from the presynaptic, and the complimentary binding sites on receptors are found on the post synaptic membrane. This makes it impossible for information to flow both directions as the neurons must go from the pre-synapse to the post-synapse.

i mentioned the movement of the presynaptic to the post synaptic but was incorrect in crediting it to diffusion. It is satisfactory to mention the receptor sites. To achieve 3 marks you must explain why it is impossible as well, instead of only mentioning the points of synaptic transmission. Using depolorisation and repolarisation is also correct, but can be a gamble and is best to leave out.

Question 2

biopsychology

briefly explain one function of the endocrine system

2 marks

Answer 2

secretes hormone in order to regulate many bodily functions (homeostasis)

i was correct in writing homeostasis but failed to explain HOW it does this (secretes hormones). It is important to remember that there are 2 marks.

Question 3

Name two glands and explain their roles

4 marks

Answer 3

adrenal gland : secretes adrenaline, invokes the fight or flight response.
pituitary gland : controls the secretion of other hormones, or causes a direct effect (causes breasts to lactate)

i achieved 2 marks simply because of failure of recall. i was able to write the adrenal gland but failed to go into greater depths on the thyroid gland and the pituitary gland.