biopsychology

Question 1

what is the structure neurons?

Answer 1

• cell body: contains the nucleus (chromosomes), from the cell body.
• dendrites: extend from the cell body and carry electrical impulses from other neurons towards the cell body.
• axon carries the impulses away from the cell body and is covered by a fatty layer of myelin sheath which increases the speed of transmission.
• nodes of ranvier: the breaks in the myelin sheath which force impulses to jump across the gaps and speed up the transmission.

Question 2

what are the types of neurons?

Answer 2

• Motor: Carry sianals from the central nervous system to the effectors (muscles/glands). Short dendrites and long axons.
• Relay: Connect sensory neurons to motor neurons or other relay neurons.
  Short dendrites and short axons.
• Sensory: Carry signals from receptors to the central nervous system. Long dendrites and short axons

Question 3

what is synaptic transmission?

Answer 3

• Neurons do not make direct contact.
• There is a very small gap between neurons called a synapse. -
• The signal needs to cross this gap to continue on its journey to, or from, the CNS.
• This is done using neurontransmitters which diffuse across the gap between the two neurons.

Question 4

what is the process for synaptic transmission?

Answer 4

1. An electrical impulse called an action potential travels along the axon of the transmitting neuron to the dendrites.
2. This triggers the nerve-ending of the pre-synaptic neuron to release neurotransmitters from synaptic vesicles.
3. These chemicals diffuse across the synapse and bind with receptor sites on the membrane of the post-synaptic neuron.
4. This stimulates the post-synaptic neuron to transmit the electrical impulse.
5. Reuptake: some of the neurotransmitter is reabsorbed back into the pre-synaptic neuron or is broken down by enzymes.

Question 5

what is the endocrine system?

Answer 5

consists of glands which produce hormones which are released in the blood stream to control vital functions of the body.

Question 6

functions of Glands and Hormones:

Answer 6

Pituitary Gland:
- Master gland that controls other glands as well, as releasing
ACTH during the stress response and oxytocin during childbirth.

Hypothalamus:
- Stimulates and activates the pituitary gland.

Pineal Gland:
- Releases melatonin to control biorhythms such as the sleep-wake cycle.

Thyroid Gland:
- Releases thyroxine to control metabolism.

Adrenal Gland:
- Adrenal medulla releases adrenaline/noradrenaline in fight
or flight. Adrenal Cortex releases cortisol in chronic stress
response.

Ovaries:
- Regulates the menstrual cycle and pregnancy by releasing oestrogen.

Testes:
- Produce testosterone for male sex characteristics and muscle growth.

Question 7

what is the fight or flight response?

Answer 7

The endocrine system and autonomic nervous system work alongside each other during the fight or flight response.

Question 8

what is the fight or flight process?

Answer 8

• A stressor is perceived in the environment
• The amyadala sends a stress sianal to the hypothalamus
• The hypothalamus activares the pituirary gland which triggers the sympathetic nervous system (SNS)
• The SNS the activates the adrenal medulla
• The adrenal medulla releases adrenaline/noradrenaline
• The release of adrenaline/noradrenaline
  prepares the body for fight or flight
• After a few minutes the parasympathetic branch activates bringing the body back to normal

Question 9

what is the role of adrenaline?

Answer 9

• Increases heartrate and breathing rate
• Dilates pupils
• Inhibits digestion and saliva production
• Increased sweat

Question 10

what is localisation?

Answer 10

the theory that specific parts of the brain are associated with particular functions