autonomic nervous system

Question 1

what does autonomic nervous system include + control

Answer 1

includes both central and peripheral nerve components and controls body element such as smooth muscle, cardiac muscle and glands

Question 2

what does the autonomic consist of

Answer 2

autonomic sensory neurons, intergrating centres in the cns and autonomic motor neurons

Question 3

what is the autonomic nervous system regulated by

Answer 3

hypothalamus and medulla oblongata

Question 4

types of peripheral motor neurons

Answer 4

pre-ganglion = efferent neuron leaves ventral horn from spinal cord (cell body in cns) nuclei in cns
post-ganglion = afferent neuron motor runs from ganglion to target tissue nuclei in ganglia

Question 5

features of post ganglia

Answer 5

usually unmyelinated
appear gray
can excite or inhibit
branched
greater spatial activation
slower response

Question 6

difference between sympathetic and parasympathetic

Answer 6

sympathetic is fight or flight response
parasympathetic is rest and digest

Question 7

difference between autonomic sensory and motor neurones

Answer 7

sensory side detects body temp, blood pressure ect = afferent
motor side modifies body temp, blood pressure ect = efferent

Question 8

key feature of post ganglionic neurons

Answer 8

unmyelinated

Question 9

contrast smooth muscle nmj ( ans) with a skeletal muscle nmj ( sns)

Answer 9

skeletal muscle nmj- typically have one or collection of neurones that have terminals on different fibres - activate more/less to get different degrees of contraction
smooth muscles nmj - 2 types : one similar to sns - neurones acting on individual nerve fibres to cause graded contraction , also have nerve axon running through muscle with varicosities (lumps) that act like end plates + release neurotransmitter all the way along

Question 10

what functions does sympathetic do

Answer 10

dilate pupils, inhibts saliva, relaxes bronchi, increases heart rate, inhibits acid secretion, increases glucose production and release, causes adrenaline secretion, inhibits bladder contraction

Question 11

what functions does parasympathetic do

Answer 11

constricts pupils, stimulates saliva production, constricts bronchi, slows heart rate, stimulates digestion, stimulates bile secretion and constricts bladder

Question 12

where is emergence of sympathetic nerves from spinal cord

Answer 12

between t1 ( first thoracic segment) and l2 ( 2nd lumbar segment) - middle of spinal cord. no cranial nerves

Question 13

where is emergence of parasympathetic nerves from spinal cord

Answer 13

cranial nerves, vagus nerve and splanchinic nerves ( top and bottom of cns) brainstem and sacral spinal cord

Question 14

difference in position of ganglion in para and sympathetic

Answer 14

parasympathetic - ganglion is near to effector organ or even in tissue ( short post ganglionic neurone )
sympathetic - ganglion closer to spinal cord ( longer post ganglionic neurone) most in sympathetic trunk

Question 15

what does the sympathetic contain that the parasympathetic doesnt

Answer 15

sympathetic trunk - where most of the ganglion are found (others are called distinct ganglion - have names)

Question 16

what system is the adrenal medulla controlled by

Answer 16

the sympathetic system

Question 17

what do the cortex and outer layers of the adrenal gland do

Answer 17

produce steroid based hormones - hydrocotrisone in human and coritocstirone in animals

Question 18

what does the adrenal medulla do

Answer 18

produces adrenaline and noradrenaline ( main neurotransmitters in sympathetic nervous system )

Question 19

does the adrenal medulla have a post ganglion neurone

Answer 19

no

Question 20

ratio (approx) for adrenaline to noradrenaline

Answer 20

17:3 - more adrenaline than noradrenaline

Question 21

where is noradrenaline also released from

Answer 21

sympathetic postganglionic nerve fibres (adrenaline only by adrenal medulla)

Question 22

4 different routes of sympathetic nervous system

Answer 22

1) bunch of neurones leave spinal cord, synapse in sympathetic trunk leave together and then spread out to effectors ( skin and sweat glands )
2) one singular neurone synapse in sympathetic trunk and then goes to effector
3) ganglion separate from sympathetic trunk, still goes through but doesn’t synapse
4) medulla - no post ganglion neurone

Question 23

what part of brain controls fight or flight response ( sympathetic)

Answer 23

allocortex if removed ‘dampens’ down sympathetic response = angry
limbic system = collection of structures in brain centre that controls emotions - main control of autonomic nervous system
hypothalamus = (part of limbic system) if just left - always in aggressive fight or flight mode, controls the sympathetic nervous system

Question 24

what does the limbic system contain

Answer 24

hypothalamus, amygdala and hippocampus are main parts

Question 25

sympathetic nervous system pathway in brain

Answer 25

goes through medulla

Question 26

where is the only source of adrenaline

Answer 26

adrenal medulla

Question 27

what does to much stress response do to horses

Answer 27

causes ulceration

Question 28

what does the shorter preganglionic neuron release in the sympathetic neuron

Answer 28

acetylcholine

Question 29

what does the longer preganglionic neuron release in the sympathetic neuron

Answer 29

noradrenaline

Question 30

what do the neurons (pre and post) release in the parasympathetic

Answer 30

both release acetylcholine

Question 31

what does the adrenal medulla release

Answer 31

adrenaline and noradrenaline

Question 32

what do the somatic neurons release

Answer 32

acetylcholine

Question 33

what are the two types of receptors

Answer 33

nicotinic and muscarinic

Question 34

where do you find muscarinic receptors

Answer 34

in the post ganglionic dendrites

Question 35

What is a catecholamine

Answer 35

any of a class of aromatic amines (both adrenaline and noradrenaline)

Question 36

two types of postsynaptic receptors for adrenaline and noradrenaline

Answer 36

alpha 1 + 2 and beta 1,2 + 3

Question 37

differences between alpha 1 and 2 receptors

Answer 37

alpha one = effects most sympathetic target tissues and activates phospholipase c as a secondary messenger
alpha two = effects GI tract and pancreas, decreases cAMP as a secondary messenger

Question 38

differences between beta 1,2 and 3 postsynaptic receptors

Answer 38

beta 1 = effects heart muscle and kidney,
beta 2 = some blood vessels and smooth muscle
beta 3 = effects adipose tissue
ALL increase cAMP as a secondary messenger

Question 39

what is homeostasis / how is it related to nervous system

Answer 39

is a dynamic balance between the autonomic branches

Question 40

what receptors respond to acetylcholine

Answer 40

cholinergic receptors (divided into nicotinic and muscarinic)

Question 41

what receptors respond to noradrenaline from presynaptic neurone + circulating noradrenaline (or adrenaline) from the adrenal gland

Answer 41

adrenergic receptors

Question 42

differences between nicotinic and muscarinic receptors

Answer 42

nicotinic receptors are channel proteins (allow cation diffusion when acetylcholine binding) , muscarinic receptors are membrane proteins that cause opening of ion channels indirectly through a 2nd messenger by phosphorylating
nicotinic = excitatory muscarinic = excitatory and inhibitory

Question 43

example of autonomic reflex

Answer 43

baroreceptor (heart?) when blood pressure increases sensory neurones fire faster + excite NTS which decrease sympathetic + increasing parasympathetic to slow down heart rate