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Flashcards in The Central nervous system Deck (20)
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1

What makes up the central nervous system?

Made up of the brain and the spinal cord

2

What makes up the peripheral nervous system

nerves

3

Structures that protect the CNS

- Bone
- The meninges
- Cerebrospinal fluid

4

Bone protecting the CNS

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

5

The meningies

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

6

Cerebrospinal fluid

- 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

7

Role of the CSF

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

8

Ridges of the cerebral cortex

Gryi

9

Folds of the cerebral cortex

Sulci

10

Longitudinal fissure

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

11

Lobes of the cerebrum

- Frontal
- Temporal
- Parietal
- Occipital

12

Three types of tracts in white matter

- 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

13

Functions of the cerebral cortex

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

14

Functioning areas of the cerebral cortex

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

15

Corpus callosum

- 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

16

Cerebellum functions

- 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

17

The hypothalamus regulates

- 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

18

Medulla oblongata

- 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

19

Spinal cord

- 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

20

Functions of the spinal cord

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