Cellular and Micro-cellular components of nervous system

Question 1

How much energy consumption does the brain account for

Answer 1

20%

Question 2

Characteristics of the neuron

Answer 2

Longevity
Do not divide
High metabolic rate

Question 3

What are the 6 types of glial cells

Answer 3

Astrocytes
Microglia
Ependymal
Oligodendrocytes
Schwann cells
Satellite cells

Question 4

Which of the 6 glial cells are neurogliail in the CNS

Answer 4

Astrocytes
Microglia
Ependymal
Oligodendrocytes

Question 5

What are the ependymal cells

Answer 5

Cells that line the cavities and ventricles of the brain and spinal cord
Can specialise as secretory epithelium and produce cerebrospinal fluid

Question 6

What is the Blood brain barrier formed by

Answer 6

Astrocytes

Question 7

What do astrocytes do

Answer 7

Help form BBB
Secrete neurotrophic factors
Provide substrates for ATP production
Take up K+, water, neurotransmitter

Question 8

What are the microglia

Answer 8

modified immune cells that act as scavengers

Question 9

What do oligodendrocytes do

Answer 9

form myelin sheath

Question 10

What is the function of schwann cells

Answer 10

Produce myelin sheath in the PNS
Protects and insulates axons
Maintains microenvironment
Assist neuronal repair
Enables Saltatory conduction

Question 11

What is a unipolar neuron

Answer 11

Single axon
Branches to connect to spinal cord or CNS neurons
Dendrits are where it receives inputs
Have chemically gated ion channels

Question 12

What neuron would you class as unipolar

Answer 12

sensory neuron

Question 13

What is a bipolar neuron

Answer 13

SIngle dendrite

SIngle axon

Question 14

Example of bipolar neuron

Answer 14

sensory neuron in ear, eye and nose

Question 15

What are multipolar neurons

Answer 15

Single myelinated axon

Multiple densrites

Question 16

What are multipolar neurons found as

Answer 16

Interneurons

Motor neurons

Question 17

Explain the pathway of noradrenaline in noradrenergic synapses

Answer 17

SYnthesied in presynaptic terminal from precursors and stored in vesicles
Released after AP
Binds to receptors
Reuptake by presynaptic neuron - reused or broken down by monamine oxidase

Question 18

What receptors do noradrenaline bind to

Answer 18

alpha2 on presynaptic

alpha1 or beta1 on postsynaptic cell

Question 19

What is alpha1 receptors involved in

Answer 19

Ocular - mydriasis (dialation)
Blood vessel - vasoconstriction
Male genitals - ejaculation
Bladder, neck and prostate - contraction

Question 20

What is the alpha2 receptor

Answer 20

Located on presynaptic terminal
Inhibits release of norepinephrine
Located in PNS and CNS

Question 21

What is beta2 receptor involved in

Answer 21

Bronchi - dialation
Uterus - relaxation of uterine smooth muscle
Arterioles in heart, lungs, skeletal muscles - vasodialation
Glycogenolysis
Enhances skeletal msucle contraction

Question 22

Passage of adrenalin

Answer 22

Synthesized in adrenal medulla
Stored in vesicles in adrenal medulla
Released into bloodstream after AP
Travels throughout the body but is metabolized by the liver

Question 23

What is the function of nicotinic receptors

Answer 23

Promotes ganglionic transmission at all ganglia

Causes skeletal muscle contraction

Question 24

What is the function of muscarinic

Answer 24

Increased gland secretion
Contraction of smooth muscle
Slow heart rate
Contraction of iris and ciliary

Question 25

Pathway of ACh

Answer 25

synthesized in presynaptic terminal from choline and acetylcoenzyme A
Stored in vesicles and released with AP
Binds to receptors on postsynaptic cell
Broken down by acetylcholinesterase
Choline is reabsorbed to synthesize more ACh

Question 26

What receptors mediate responsed to adrenaline and noradrenaline

Answer 26

Adrengenic receptors like Alpha and beta

Question 27

What receptors mediate responsed t acetylcholine

Answer 27

Cholinergic receptors like muscarinic