Topic 9.4 Structure and function of the mammalian nervous system

Question 1

Name the two main divisions of the nervous system

Answer 1

Central nervous system

Peripheral nervous system (all neurons that are not part of the CNS).

Question 2

Describe the central nervous system

Answer 2

Comprised of brain and spinal cord.

Specialised system of nerve cells processes stimuli and propogates impulses.

Question 3

Name the two main divisions of the peripheral nervous system.

Answer 3

Voluntary (under conscious control)

Autonomic (not under conscious control)

Question 4

Name the two main division of the autonomic nervous system

Answer 4

Sympathetic

Parasympathetically

Act antagonistically to regulate response of effectors e.g. heart rate

Question 5

Describe the sympathetic nervous system

Answer 5

• Usually stimulates effectors (coordinates fight-or-flight response).
• Neurotransmitter noradrenaline.
• Ganlia are located near CNS

Question 6

Describe the parasympathetic nervous system

Answer 6

• Usually inhibits effectors (coordinates rest/digest response).
• Neurotransmitter actylcholine.
• Ganglia located far from CNS.

Question 7

Describe the structure of the spinal cord

Answer 7

Cylindrical bundle of nerve fibres runs from brain stem to lower back. Surrounded by spinal vertabrae.

Consists of nerve tissues (neurons, glia, ganglia, blood vessels). 31 Pairs of spinal nerves.

Grey matter: H-shaped region contains neurons
White matter: myelinated axons

Question 8

Name the groups of the spinal nerves

Answer 8

Cervical spinal nerves = signals to back of head

Thoracic spinal nerves = signals to chest and back muscles

Lumbar spinal nerves = signals to lowwer abdomen and back

Sacral spinal nerves = signals to thighs and lower legs

Coccygeal nerve transmits from skin on lower back

Question 9

Identify the location and function of the cerebellum

Answer 9

Located in the back lower portion of the brain.

• Controls execution (not initiation) of movement e.g. timing, balance, coordination, posture.
• Possible role in cognition e.g. attention and language.

Question 10

Identify the location and function of the medulla oblongata

Answer 10

Located at the base of the brain.

Controls a range of autonomous functions, including breathing and heart rate (location of cardioacceleratory/ deceleratory centres).

Question 11

Identify the location and function of the cerebrum

Answer 11

Uppermost part of the brain is organised into lobes which control voluntry functions e.g. initiating movement, speech, thought.

Question 12

Identify the location and function of the hypothalamus

Answer 12

Between cerebrum and medulla oblongata in middle of the brain.

Includes anterior pituitary gland (secretes metablolic and reproductive hormones).

Involved in thermo and osmoregulation.