Biopsychology exam questions + answers

Q1. Give one difference between the autonomic nervous system and the somatic nervous system. (1 mark)

[AO1 = 1]

• The autonomic nervous system is involuntary whereas the somatic nervous system is under conscious control.
• ANS controls smooth muscles and glands whereas the SNS controls skeletal muscles. 

Q2. Identify the two components of the peripheral nervous system, and explain two differences in thioer organisation and/or functions. (4 marks)

[AO1 = 2   AO3 = 2]

One mark each for components of the peripheral nervous system - the somatic nervous system (SNS) and the autonomic nervous system (ANS).

Plus

One mark for each for relevant difference explained.

• the SNS has sensory and motor pathways, while the ANS is purely motor;
• the ANS controls internal organs and glands of the body while the SNS controls skeletal muscle, movement etc;
• ANS control centres are in the brain stem whilst SNS carries commands from the motor cortext. 

Q3. Briefly outline how excitation and inhibition are involved in synaptic transmission. (4 marks)

[AO1 = 4]

Possible Content:

• Neurotransmitters can be excitatory or inhibitory (most can be both but GABA is purely inhibitory).
• If the neurotransmitter is excitatory then the post synaptic neuron is more likely to fire an impulse.
• If the neurotransmitter is inhibitory then the post synaptic neuron is less likely to fire an impulse. 
• The excitatory and inhibitory influences are summed. If the net effect on the post synaptic neuron is inhibitory, the neuron will be less likely to 'fire' and if the net effect is excitatory, the neuron will be more likely to fire. 

Q4. Outline the structures and processes involved in synaptic transmission. (6 marks) 

[AO1 = 6]

Content:

The synaptic cleft; pre and post synaptic membranes; postsynaptic receptor sites, neurotransmitters in vesicles in the presynaptic terminal, release of neurotransmitters into the synaptic cleft when stimulated by nerve impulses (action potentials) arriving at the presynaptic terminal, combination of neurotransmitters wiht postsynaptic receptors; postsynaptic effects either excitatory (depolarisation) or inhibitory (hyperpolarisation).

Q5. Raoul has recently been prescribed a drug for mental illness. He looks on the interent to find out more about the drug but he does not undertsand the phrase 'synaptic transmission'. 

Write a brief explanation of synaptic transmission in the brain to help Raoul to understand how his drug might work. (3 marks)

[AO2 = 3]

1 mark for any three of the following points:

• Transmission involves impulses crossing a space or gap beteen an axon terminus and the adjacent neuron (the synapse/synaptic cleft)
• Neurotransmitters are chemicals released from vesicles on the presynaptic neuron 
• They travel/diffuse across the synapsenand lock onto receptor sites on recieveing/postsynaptic neuron
• Some neurotransmitters increase the rate of firing in the receiving neurons and others decrease the rate of firing
• Psychoactive drugs work by affecting (increasing or inhibiting) the transmission of neurotransmitters across the synapse 

Q12. You are walking home at night. it is dark and you hear someone running behind you. Your breathing quickens, your mouth dries and your heart pounds. Then you hear your friend call…