Cells and Tissues of the Nervous System

Question 1

What kind of cells are neurons?

Answer 1

Excitable cells

Question 2

What are impulses through neurons carried as?

Answer 2

Action potentials

Question 3

What kind of cells are glial cells?

Answer 3

Non-excitable supporting cells

Question 4

What is the cytoplasm in the cell body of a neuron called?

Answer 4

Perikaryon

Question 5

What is the cytoplasm in the axon of a neuron called?

Answer 5

Axoplasm

Question 6

What are dendrites stimulated by?

Answer 6

Environmental changes of the activities of other cells

Question 7

What does the cell body of a neuron contain?

Answer 7

Nucleus
Mitochondria
Ribosomes
+ other organelles

Question 8

What does the axon of a neuron do?

Answer 8

Conducts nerve impulses (AP) toward synaptic terminals

Question 9

What does the synaptic terminals do?

Answer 9

Affect another neuron or effector organ (muscle or gland)

Question 10

What is the role of the myelin sheath?

Answer 10

Increases conduction speed in axons by saltatory conduction

Question 11

What is the myelin sheath formed by in the PNS?

Answer 11

Schwann cells

Question 12

What is the myelin sheath formed by in the CNS?

Answer 12

Oligodendrocytes

Question 13

What is the clinical importance of the myelin sheath in multiple sclerosis?

Answer 13

Patchy loss/scarring of myelin sheath (demyelination) results in nerve conduction across affected axons to be abnormal = MS

Question 14

What do glial cells in the CNS do?

Answer 14

Ependymal cells - Line ventricles

Question 15

What do glial cells in the PNS do?

Answer 15

Satellite cells - Surround neuronal cell bodies

Question 16

What do glial cells in the CNS contain?

Answer 16

Astrocytes
Oligodendrocytes
Microglia

Question 17

What do astrocytes do?

Answer 17

Have end feet = surround synapses and capillaries

Help in K+ buffering

Question 18

What do oligodendrocytes do?

Answer 18

Myelination

Question 19

What do microglia?

Answer 19

Phagocytosis

Scar tissue formation

Question 20

What do glial cells in the PNS contain?

Answer 20

Schwann cells

Question 21

What do schwann cells do?

Answer 21

Myelination

Question 22

What is the blood brain barrier?

Answer 22

A protective mechanism that helps to keep a stable environment for the brain
Prevents harmful amino acids and ions in bloodstream + blood cells entering the brain

Question 23

Where are the exceptions where the BBB is absent?

Answer 23

In a few ‘circumventricular’ organs (e.g. parts of hypothalamus, posterior pituitary)

Question 24

What is the basic role of the cerebrum?

Answer 24

Consciousness

Question 25

What is the basic role of the cerebellum?

Answer 25

Balance and coordination

Question 26

What is the basic role of the brainstem?

Answer 26

``` Vital centres (e.g. cardioresp.) Pathway for fibre tracts ```

Question 27

What are the lateral ventricles?

Answer 27

C-shaped cavities that lie in the cerebral hemispheres

Question 28

What is the interventricular forament?

Answer 28

Connects lateral ventricles with the 3rd ventricle

Question 29

Where is the 3rd ventricle?

Answer 29

Cavity within the diencephalon

Question 30

Where is the cerebral aqueduct?

Answer 30

Lies in the midbrain

Question 31

Where is the 4th ventricle?

Answer 31

Lies in the hindbrain

Question 32

What is the dura mater structure like?

Answer 32

Tough Fibrous Has dural folds

Question 33

What is the pia mater structure like?

Answer 33

Vascularised | Dips into folds of the brain

Question 34

What is the subdural space?

Answer 34

Potential space traversed by blood vessels penetrating into the CNS

Question 35

What does the subarachnoid space contain?

Answer 35

CSF

Question 36

What is CSF?

Answer 36

Fluid inside the cavity of the brain and central canal of the spinal cord Also present surrounds brain and spinal cord between meninges layers

Question 37

What is the CSF responsible for?

Answer 37

Maintaining intracranial pressure

Question 38

Where is CSF present?

Answer 38

Inside ventricles | Between pia and arachnoid

Question 39

Where is CSF formed?

Answer 39

By choroid plexus in each ventricle

Question 40

Where is CSF absorbed?

Answer 40

By arachnoid villi into sagittal sinus (venous channel in brain)