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Flashcards in Chapter 11 Deck (47):
1

What is dual innervation ?

Both branches of ANS innervate most effector organs

2

Primary function of ANS

regulate organs to maintain homeostasis

3

What are the two neurons fron CNS to effector organs

Preganglionic neuron
Postganglionic neuron

4

Purpose of autonomic ganglia

communication from preganglionic to postganglionic neuron

5

What are intrinsic neurons?

modulate the flow of information to the target organs

6

What are the effector organs

Cardiac muscle
Smooth muscle
Glands
Adipose tissue

7

Where do preganglionic neurons originate?

Thoracolumbar spinal cord

8

Preganglionic exits via what

Ventral root of spinal cord and enters spinal nerve

9

Pathway for postganglionic

Leave ganglia as gray ramus and re-enter spinal nerve
Travel to effector organ in spinal nerve

10

Where do preganglionic neurons originate?

brainstem or sacral spinal cord

11

two primary receptors in the nervous system are what?

Acetylcholine and norepinephrine.

12

Acetylcoline what type of neurons

Preganglionic, parasympathetic postganglionic and sympathetic postganglionic

13

Hormones of the Adrenal Medulla and percentages

80% epinephrine and 20% norepinephrine, small amount of dopamine

14

Cholinergic means it releases what?

releases acytelcholine

15

Purpose of nicotinic cholinergic receptors?

Open channels for cations, results in depolarization. Excitatory effect on target cell

16

What is muscarinic cholinergic receptors?

Coupled to G protein, response triggered by binding of acyteylcholine depends on target cell

17

what class of cholinergic receptor found in autonomic postganglionic ? Effector organ for parasympathetic? Skeletal muscle?

Nicotinic, muscarinic, and nicotinic

18

Two main classes of adrenergic receptors.

Alpha and Beta. All coupled to G proteins

19

How many subclasses for alpha and beta

2 alpha 3 beta

20

Where are alpha adrenergic receptors located? Affinity is greater for what?

Effector organs of sympathetic nervous system, norepinephrine

21

What can be said about all Beta adrenergic receptors?

All activate cAMP

22

Where are Beta 1 Adre. Receptors located? Excitory or inhibitory? What about affinity for epinephrine and norep.

cardiac muscles and kidneys. Usually excitory, equal affinity.

23

Beta 2 located where? Inhibitory? Greater affinity for what?

some blood vessels and smooth muscle. Yes. Greater affinity for epinephrine.

24

beta 3 located where?

Adipose tissue. Excitory, equal affinity.

25

What is autonomic neuroeffector junctions?

Synapses between efferent and effector organ in ANS

26

Neurotransmitter stored where for Neuroeffector junction?

Axon swellings called varicosites. In response to action potential in postganglionic neuron.

27

Events at the neuroeffector junciton (6)

1. Action potential arrives at varicosity.
2. Voltage-gated Ca2+ channels open.
3. Ca2+ triggers exocytosis of neurotransmitter.
4. Neurotransmitter binds with receptors on effector organ.
5. response in effector organ.
6. Neurotransmitter degraded, diffuses away, reuptake.

28

What is increased and decreased during parasympathetic activity

Increase in gastrointestinal activities and decrease in heart rate and blood pressure

29

msot changes in ANS accomplished through what?

visceral reflexes(changes in the functions of organs that occur in response to changing conditions in the body

30

What do the hypothalamus, pons and medulla maintain?

Homeostasis

31

Waht do cerebral cortex and limbic system control

emotions

32

How many neurons between CNS and effector organ in SNS

one-motor neuron

33

what is the effector organ in SNS

Skeletal muscle

34

SNS originate from where?

Ventral Horn

35

What is the neurotransmitter for SNS

Acetylcholine

36

What are the receptors in skeletal muscle

Nicotinic cholinergic

37

What is a motor unit

Motor neuron and the muscle fibers it innervates

38

How many muscle fibers does a motor unit innervate

MAny

39

What is a neuromuscular junction

Synapse between a motor neuron and a muscle fiber

40

What are the two anatomical portions of the neuromuscular junction?

Terminal button= axon terminal and motor end plate= specialized muscle membrane at junction

41

All motor neurons release what?

Acetylcholine

42

What type of receptors are on skeletal muscle cells

nicotinic cholinergic

43

All synapses are what for neuromuscular junction

Excitatory

44

what degrades acetylcholine in synaptic cleft

Acetylcholinesterase

45

Activation of motor neuron depends on what

Summation os EPSPs and IPSPs

46

Action potential in motor neuron triggers what

release of acetylcholine at neuromuscular junciton

47

8 steps of cummunicaiton at the neuromuscular junciton

1. Action potential arrives at terminal button.
2. Voltage-gated calcium channels open.
3. Calcium enter cell triggering release of ACh
4. ACh diffuses accross cleft and binds to nicotinic receptors on motor end plate
5.ACh triggers opening of channels for small cations sodium and potassium
6.Net movement of positive charge in = depolarization
7. EPP causes action potential in muscle cell
8. Action potential spreads through muscle causing contraction