nervous system and autonomic nervous system

Question 1

name the 3 layers of highly vascularised CT that separates the brain from nervous tissues.

Answer 1

pia mater - innermost, attached tightly to surface of brain and spinal cord

arachnoid mater - highly elastic, network of blood vessels in poorly protected sub-arachnoid space.

dura mater - outermost layer, “hard mother”, further divided to periosteal and meningeal layers

Question 2

what purpose does cerebral spinal fluid hold?

Answer 2

nourishes brain, protection by floating.

Circulates through subarachnoid space, via ventricles

Question 3

what is the function of the blood brain barrier?

Answer 3

controls substances that reach cells of CNS from bloodstream

Question 4

what three regions do neurons divide into?

Answer 4

dendrites - incoming signals

soma - central cell body

axon - outgoing info

Question 5

define Guillain Barre syndrome

Answer 5

autoimmune destruction of Schwann cells in PNS

Question 6

motor neurons

Answer 6

part of CNS, connect to muscles, glands, organs.

From spinal cord to skeletal muscles/smooth muscles

Question 7

sensory neurons

Answer 7

activated by sensory input from environment

Question 8

afferent signal

Answer 8

PNS, sensory signal towards the brain.

Question 9

efferent signal

Answer 9

CNS, motor arms, away from brain to muscle

Question 10

what two classes are nervous system classified into?

Answer 10

neuronal - CNS

ganglia - PNS

Question 11

neuropathic pain

Answer 11

pain arises from the damage to the somatic nervous system

Question 12

nociceptive pain

Answer 12

results from the activation of pain receptors (nociceptors), indicating POTENTIAL HARM!

Question 13

What is the Autonomic Nervous System?

Answer 13

controls all involuntary functions

heart rate, blood pressure, digestion,

Question 14

Sympathetic Nervous System

Answer 14

Responsible for the ‘fight or flight’ response, triggered by stressful situations.

Arises from the thoracic and lumbar divisions of the spinal cord; T1-T12 and L1-L2, thoracolumbar

Question 15

Parasympathetic Nervous System

Answer 15

Regulates basal activities, ‘rest and digest’.

Arises from the brainstem and sacral spinal cord cranio-sacral; c1-C7 and L1-L5

Question 16

Actions of the Autonomic Nervous System on pre-ganglion cells

Answer 16

the same for sympathetic and parasympathetic

neurotransmitter released is acethylcholine

act on nicotinic receptors

Question 17

Actions of the Autonomic Nervous System on post-ganglionic cells

Answer 17

differ b/w sympathetic and parasympathetic

sympathetic release noradrenaline and act on adrenoreceptors of tissue

parasympathetic release acetylcholine and act on muscarinic receptors on tissue

Question 18

noradrenaline can have opposing effects on the same types of tissues located in different parts of the body depending on adrenergic receptor. what are they?

Answer 18

α1 - Smooth muscle contraction, notably in blood vessel walls

α2 - Various effects in CNS

β1 - Increased heart rate and cardiac output

β2 - Smooth muscle relaxation; in bronchi, bladder, blood vessel walls

Question 19

vasovagal syncope

Answer 19

sudden fainting

caused by fear, pain, prolonged standing, phobias

Question 20

common drugs targeting sympathetic nervous system

Answer 20

beta antagonist - salbutamol for asthma, stimulates beta 2 receptor

beta blockers - atenolol for heart, antagonise beta 1 receptor

alpha blockers - relax muscles, antagonise alpha 1