Biopsychology

Question 1

Nervous system is made up of

Answer 1

cells that transmit messages around the body to respond to the surrounding.

Question 2

Central nervous system AO1

Answer 2

• Complex thought processes and commands to the rest of the body.
• Transferral of messages to and from brain to PNS.
• Made up of Brain and spinal.

Question 3

Peripheral nervous system AO1

Answer 3

• Transmits info to and from CNS to the body.

- Has two branches; autonomic nervous system and somatic nervous system.

Question 4

Autonomic nervous system AO1

Answer 4

• Transmits info to and from non-voluntary organs and systems (e.g. heart rate).
• Only motor pathways.
• Controls internal organs and glands.
• Two branches that are antagonistic; sympathetic (triggered in response to stress) and parasympathetic (returns body back to normal state).

Question 5

What is the endocrine system made up of?

Answer 5

Glands and hormones.

Question 6

What is the role of the endocrine system?

Answer 6

Regulates hormone production from glands which are required for essential body functions.

Question 7

What does the hypothalamus control?

Answer 7

Controls the release of hormones from pituitary gland..

Question 8

What does the pituitary gland control?

Answer 8

Controls release of hormones from other glands in the body, e.g. ACTH which stimulated the adrenal medulla causing them to secrete adrenaline into the bloodstream.

Question 9

What does the pineal gland release?

Answer 9

Releases Melatonin when somatic nervous system detects low levels of light, which regulates the sleep-wake cycle.

Question 10

What do the adrenal glands release?

Answer 10

Releases adrenaline and noradrenaline into the blood; this prepares the body for fight or flight by constricting blood vessels in the stomach (inhibiting digestion) and increases your heart rate.

Question 11

What do ovaries do?

Answer 11

Facilitates the release of the hormones oestrogen and progesterone.

Question 12

What do testes do?

Answer 12

Facilitates the release of the hormone testosterone.

Question 13

Fight or flight response AO1

Answer 13

1. body senses and becomes aware of a stressor in the environment.
2. Via sensory receptors and sensory neurons in the PNS, this info is sent to the hypothalamus.
3. Hypothalamus coordinates response and triggers increased levels of activity in the sympathetic branch of the ANS.
4. Adrenaline is released by adrenal medulla in the adrenal glands, and is transported in the blood to target effectors through the action of the endocrine system.
5. Results in rectum contracting, inhibited saliva production and increased breathing rate - this creates the physiological response needed to sustain the fight or flight response.
6. Once the stressor is no longer a threat, as part of the antagonistic pairing, the hypothalamus triggers less activity in the sympathetic branch and more activity in the parasympathetic branch of the ANS.
7. Triggers the rest and digest response which decreases the activity originally increased by the sympathetic branch.

Question 14

Fight of flight response AO3

Answer 14

• Contradictory evidence - Gray (1988) suggests first response to danger is to freeze not fight or flight - more common for people who want to avoid confrontation altogether, hence the ‘freeze’ response.
• Doesn’t fully explain stress in females - Taylor et al (2002) females adopted ‘tend and befriend’ response; highlights beta bias as psychs assumed females respond in same way as males until Taylor provided evidence - explanation limited but has prompted more recent research providing explanation for females.
• In modern life fight or flight may be maladaptive - stressors in modern life tend to not require you to fight or flee from so physiological responses not needed - repeated stress can cause damage to blood vessels + contribute to heart disease, therefore stress response can hinder rather than help survival.

Question 15

Motor neuron structure and function

Answer 15

• Connects CNS to muscles/glands and helps organs, glands and muscles function.
• Is multipolar (has a single axon and many dendrites allowing the integration of lots of info from other neurons).

Question 16

Relay neuron structure and function

Answer 16

• Relays info from sensory neurons to motor neurons and other relay neurons.
• Found in the brain and spinal cord.
• Is multipolar (has a single axon and many dendrites allowing the integration of lots of info from other neurons).

Question 17

Sensory neuron structure and function

Answer 17

• Transfers messages from PNS to CNS.
• Found in receptors and carry nerve impulses to the spinal cord and brain.
• Is unipolar and only goes one way.

Question 18

Structure and function of neurons AO1

Answer 18

• Cell body (stoma) contains genetic material.
• Dendrites (branches) transfer impulses from other neurons and carry the impulse to the cell body.
• Axon is a long fibre which carries nerve impulses (electrical signal - action potential) and is covered in myelin sheath (except gaps called nodes of Ranvier which the impulse jumps to).
• Axon terminal (connects one neuron to another).

Question 19

What charge does a neuron have when it is resting inside a cell compared to the outside of a cell?

Answer 19

It is negatively charges compared to the outside.

Question 20

What is synaptic transmission?

Answer 20

The process by which neighbouring neurons communicate which each other by sending chemical messages across the synapse that separates them.

Question 21

What are neurotransmitters?

Answer 21

Brain chemicals released from synaptic vesicles that relay signals across the synapse from one neuron to another. Neurotransmitters can be broadly divided into those that perform excitatory function and those that perform an inhibitory function.

Question 22

What is summation?

Answer 22

Process that decides whether a postsynaptic neuron fires.
- The excitatory and inhibitory influences are summed; if the net effect on the postsynaptic neuron is inhibitory then it is less likely to fire; if the net effect is excitary it is more likely to fire.

Question 23

What is excitation?

Answer 23

When a neurotransmitter, such as adrenaline, increases the positive charge of the postsynaptic neuron. This increases the likelihood that the neuron will fire and pass on the electrical impulse.

Question 24

What is inhibition?

Answer 24

When a neurotransmitter, such as serotonin, increases the negative charge of the postsynaptic neuron. This decreases the likelihood that the neuron will fire and pass on the electrical impulse.

Question 25

What is an action potential?

Answer 25

The creation of an electrical impulse that travels down the axon towards the end of the neuron.

Question 26

Process of synaptic transmission AO1

Answer 26

1. An electrical impulse passes down the axon of the first neuron.
2. Vesicles holding neurotransmitters move towards the presynaptic membrane.
3. Vesicles attach to the presynaptic membrane and release neurotransmitters into the synaptic cleft.
4. Neurotransmitters diffuse across the synapse and attach to receptors on the postsynaptic membrane.
5. Activity in the receptors causes change in the second neuron which increases or decreases the likelihood of an action potential in the second neuron.
6. Neurotransmitter molecules are recycled into the presynaptic neuron.