The Central nervous system

Question 1

What makes up the central nervous system?

Answer 1

Made up of the brain and the spinal cord

Question 2

What makes up the peripheral nervous system

Answer 2

nerves

Question 3

Structures that protect the CNS

Answer 3

• Bone
• The meninges
• Cerebrospinal fluid

Question 4

Bone protecting the CNS

Answer 4

The brain is protected by the cranium, and the spinal cord runs through an opening in the vertebrae called the vertebral canal

Question 5

The meningies

Answer 5

The meninges are found inside the bones, and covering the surface of the brain and spinal cord. They are made up of three layers of connective tissue including:

• The dura mater (attached to the bone)
• The arachnoid
• The sub-arachnoid space
• And the pia mater

Question 6

Cerebrospinal fluid

Answer 6

• Occupies a space between the middle and inner layers of meninges
• It also circulates through cavities in the brain and through a canal in the centre of the spinal cord
• Is a watery fluid containing a few calls and some glucose, protein, urea and salts

Question 7

Role of the CSF

Answer 7

• To act as a shock absorber
• To support the brain
• To transport nutrients

Question 8

Ridges of the cerebral cortex

Answer 8

Gryi

Question 9

Folds of the cerebral cortex

Answer 9

Sulci

Question 10

Longitudinal fissure

Answer 10

A deep grove that almost separates the cerebrum into two halves, the cerebral hemispheres

Question 11

Lobes of the cerebrum

Answer 11

• Frontal
• Temporal
• Parietal
• Occipital

Question 12

Three types of tracts in white matter

Answer 12

• Connect various areas of the cortex within the same hemispheres
• Carry impulses between the left and right hemispheres
• Connect the cortex to other parts of the brain or to the spinal cord

Question 13

Functions of the cerebral cortex

Answer 13

• Thinking, reasoning, learning
• Memory
• Intelligence
• Sense of responsibility
• Perception of the senses
• Initiation of voluntary muscle contraction

Question 14

Functioning areas of the cerebral cortex

Answer 14

• Sensory areas: interpret impulses from receptors
• Motor areas: controls muscular movements
• Association areas: concerned with intellectual and emotional processes

Question 15

Corpus callosum

Answer 15

• A wide band of nerve fibres that lie underneath the cerebrum at the base of the longitudinal fissure
• Nerve fibres in the corpus callosum connect the left and right hemispheres of the brain

Question 16

Cerebellum functions

Answer 16

• Exercises control over posture and balance
• Co-ordination of voluntary muscle movement
• Receives sensory information from the inner ear
• Receives sensory information from stretch receptors in the skeletal muscles
• All processes are sub-conscious

Question 17

The hypothalamus regulates

Answer 17

• The autonomic nervous system (HR, BP, digestive juices, movement of alimentary canal, pupil diameter)
• Body temperature
• Food and water intake
• Patterns of waking and sleeping
• Contractions of urinary bladder
• Emotional responses
• Secretion of hormones

Question 18

Medulla oblongata

Answer 18

• It is a continuation of the spinal cord
• It is about 3cm long and extends from just above the point where the spinal cord enters the skull
  Contains:
• The cardiac centre: regulates the rate and force of the heart beat
• Respiratory centres: control rate and depth of breathing
• Vasomotor centre: regulates diameter of blood vessels

Question 19

Spinal cord

Answer 19

• a cylindrical structure that extends form the foramen magnum to the L2
• approximately 44cm long
• enclosed in the vertebral canal
• three meningeal layers
• the dura mater is not joined to the bone, allowing the cord to bend when the spine is bent
• white matter surrounds the grey

Central canal contains CSF

Question 20

Functions of the spinal cord

Answer 20

• carry sensory impulses up to the brain and motor impulses down from the brain
• integrate certain reflexes