U3 Nervous system: Central nervous system

Question 1

What are nerves in the central nervous system called and what are the two types?

Answer 1

• Tracts
• Ascending tracts which move up the spinal cord
• Descending tracts which move down the spinal cord

Question 2

Cerebrum

Answer 2

• Largest part of the brain
• Has an outer layer of grey matter (cerebral cortex) made up of axons and cells bodies and is where processing occurs

The cerebral cortex is involved in:
- high order functions: thinking, learning, memory
- perception of senses
- initiation of voluntary muscle contraction

The cerebral cortex can be divided into three main functional areas:
- sensory areas: interpret impulses from receptors
- motor areas: control muscular movements
- association areas: intellectual and emotional processing

• Below the cerebral cortex is white matter made up of myelinated axons

Question 3

Corpus callosum

Answer 3

• A band of nerve fibres (white matter) underneath the cerebrum
• The fibres are myelinated and relay information between the hemispheres of the brain

Question 4

Thalamus

Answer 4

A relay station that all sensory information passes through before going to the cerebrum

Question 5

Hypothalamus

Answer 5

• A controller of body activities related to homeostasis
• Has a role in coordinating parts of the endocrine system by acting through the pituitary gland
• Regulates metabolism, growth, reproduction and response to stress

Question 6

Pituitary gland

Answer 6

A master gland which controls other endocrine glands by producing hormone

Question 7

Cerebellum

Answer 7

Controller of posture, balance and fine muscle coordination of voluntary muscle movements

Question 8

Pons

Answer 8

• Coordinates and transmits information between the cerebral cortex, cerebellum and spinal cord
• Contains respiratory centres
• Works with the medulla oblongata

Question 9

Medulla oblongata

Answer 9

• Joins the brain to the spinal cord

Contains reflex centres that coordinate different activities
- Cardiac centre: regulates heart rate
- Respiratory centre: controls breathing rate
- Vasomotor centre: regulates blood pressure by controlling the diameter of blood vessels

• Controls vomiting, coughing and sneezing reflexes
• Controls reflexes in head area such as blinking

Question 10

Spinal cord

Answer 10

Provides a pathway for communication between muscles, glands and the brain and the integration of autonomic and protective reflexes

Question 11

What are the lobes of the brain, their functions and areas they contain?

Answer 11

Frontal lobe
- Problem solving, emotions, personality, language
- Primary motor cortex
- Primary olfactory cortex
- Prefrontal cortex

Parietal lobe
- Processes temperature, touch, tastes and pain
- Primary sensory cortex
- Primary association area

Occipital lobe
- Processes vision
- Primary visual cortex
- Visual association area

Temporal lobe
- Recieves auditory information
- Primary auditory cortex
- Audtory association area