Module 3 Homeostasis and Structure of the Nervous System Flashcards

1
Q

Define homeostasis

A

The body maintaining a constant environment and changes in conditions that challenge its constant environment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Stages of maintaining homeostasis

A

Senses detect changes, integration centres stimulate effectors (interprets signals), effectors respond to changed conditions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Define positive and negative feedback

A

Whether the changes require a positive or negative feedback from body (concept)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is positive feedback

A

When the environment is stable and constant, the body doesn’t have to do anything but continue its processes and maintain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is negative feedback

A

When theres changes in the environment that the internal environment needs to adjust to and revert back to constant state. Adjustments cease when set point is reached

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Difference between endocrine and nervous system

A

endocrine is slow, duration is long and more general, nervous is fast, duration is short more specific

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What does the central nervous system (CNS) consist of

A

Brain, spinal cord,

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what is part of the Peripheral nervous system

A

all other nervous tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

describe features of the brain

A

Located in the cranial cavity, surrounded by meninges, bathed in cerebrospinal fluid (the brain moves around in this fluid and provides nutrients), dense collection of neurons (receiving info, integrated and determining what to do), has white matter (cable of information coming in and out of centre) and grey matter (Processing centre).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Name the 4 regions of the brain

A

Cerebrum, Diencephalon, cerebellum, brainstem

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Which is the largest part of the brain

A

Cerebrum- generates conscious thought, responsible for memory, reasoning emotions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

which region of the brain is the main junction for sensory inputs

A

Diencephalon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the fluid that protects the brain called and where is it formed

A

Cerebrospinal fluid, made in ventricles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Which region of the brain generates breathing patterns and heart rhythm

A

Brain stem

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

which cells produce cerebrospinal fluid

A

ependymal cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

which cells protect neurons from bacteria

A

microglial cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Name the 5 spinal nerves and where they are

A

cervical(neck), thoracic (chest) , lumbar (abdomen), sacral (pelvis), coccygeal (tailbone).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is a nerve

A

A collection of neurons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Define neuron

A

functioning cells generating an electrical signal, a nerve is a collection of them.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is afferent

A

Afferent means it will come out and COME INTO the spinal chord and AFFECT the nervous system. Sensory nerve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is efferent

A

Efferent is coming out of the central nervous system and is AN EFFECT of the CNS. Motor nerve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What parts of the body do spinal nerves receive/ transmit signals to

A

all over the body not so much the head

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What parts of the body do cranial nerves receive/transmit signals to

A

Mostly the head, but vagus goes to all over the body.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Name the parts of a neuron

A

Dendrites, cell body, axon, axon terminal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

How do neurons generate electrical signals

A

Occurs because of difference in charge over gradient, cation leaks out of cells and causes a charge

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is a voltage difference

A

Potassium leaks back out causing an imbalance inside becomes negative and outside becomes positive, allows neurons to generate electrical signals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

How are signals stimulated

A

dendrites pick up signals, cell body integrates, sends to axon if threshold is reached an action potential is formed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

where does action potential occur

A

at axon hillock

29
Q

Where in the spinal cord do sensory neurons enter?

A

dosal surface (SAD)

30
Q

Where is the most basic integration of sensory input?

A

at the receptor field and goes into the spinal cord

31
Q

describe the path of a sensory stimulus from receptor ti the sensory cortex

A
  1. receptor field to spinal cord 2. up spinal cord to thalamus 3. thalamus to cortex
32
Q

what is the most basic level of control of the somatic system

A

spinal cord

33
Q

where in the spinal cord do motor neurons emerge from

A

ventral- efferent

34
Q

what is the highest level of control of the somatic system

A

cerebellum

35
Q

what is the parasympathetic system

A

rest and digest.

36
Q

what are the effects of the cranial nerves

A

constrict pupils, saliva secretion, nasal secretion

37
Q

what are the effects of the vagus nerve

A

increase secretion, muscle contraction, relax sphincter , glucose uptake(liver), contracts gallbladder

38
Q

What are the vagus effects on the cardiovascular system

A

reduce heart rate, constrict bronchioles

39
Q

what is the sympathetic system

A

fight or flight- from thoracic and lumbar nerves, ganglia in spinal cord or plexus

40
Q

Give an example of negative feedback

A

Thermorecptors detect temperature, brain integrates signals and alters blood flow, alters muscle activity, alters behaviour, ceases alternation when normal

41
Q

an example of positive feedback

A

a tear. platelet system: some platelets on site, release chemical to attract more, platelet plug is fully formed.

42
Q

example of endocrine response

A

blood glucose. pancreas senses glucose, releases insulin, liver stores glucose, tissue takes up more glucose

43
Q

example of nervous response

A

blood pressure. sensors detect decrease, brain integrates response, HR increases -vasoconstriction, BP returns to normal

44
Q

what is the cation inside the cell

A

potassium

45
Q

what is the cation outside the cell

A

sodium

46
Q

how is an action potential formed- basic

A

axon reaches threshold, tells cell to transmit signal start AP occurs at axon hillock

47
Q

describe the net effect

A

depolarisation- sodium enters cell, repolarisation - sodium stops entering, potassium leaves, hyper polarisation - too much potassium leaves cell.

48
Q

describe saltatory conduction

A

Action potential propagating down a myelinated neuron. action potentials in myelinated neurons: gaps in myelin = nodes of Ranvier, AP travels faster down the axon

49
Q

what is absolute refractory period

A

when an action potential cannot be created, occurs when there is already one in progress

50
Q

what is relative refractory period

A

when it is difficult to stimulate an action potential (axon less sensitive), when cell is hyper polarised

51
Q

what is a synapse

A

the gap between the action potential and target cell, signal to release neurotransmitter. neurotransmitter affects target cell

52
Q

describe the components of the synapse

A

presynaptic neuron, postsynaptic target, synaptic cleft, neurotransmitter, receptor for neurotransmitter

53
Q

describe the conversion of a signal

A

voltage gated sodium channels open in synapse and lets calcium in = vesicle binds membrane, vesicle releases neurotransmitter to synapse.

54
Q

movement of which ion is mostly responsible for resting membrane potential

A

potassium and moves out of cells

55
Q

which ion triggers vesicle fusion and neurotransmitter release in the axon terminal

A

calcium

56
Q

what 5 structures does the cortex have

A

frontal, parietal, occipital, temporal, insular.

57
Q

what functional areas does the cortex have

A

sensory, motor, association areas

58
Q

name the functional associated areas

A

premotor and motor, somatosensory and somatosensory association, primary visual and visual association, auditory and auditory association

59
Q

what is the pre-frontal cortex responsible for

A

memory and reasoning

60
Q

what is the posterior association responsible for

A

sensing environment

61
Q

what is the limbic system responsible for

A

emotions

62
Q

where is the thalamus and what does it do

A

in diencephalon, relays sensory neuron input to sensory cortex(s)

63
Q

where is the hypothalamus and what does it do

A

in diencephalon, involuntary signal integration, homeostatic control centre, regulates hormone secretion

64
Q

what does the cerebellum do in terms of regulating signals

A

fine control of motor activity, received information from sensory receptors, motor cortex and sensory areas, fine tunes motor cortex output

65
Q

what does the brain stem do

A

controls visual+auditory reflexes, regulates respiratory rate, controls heart rate, blood vessels, generates respiratory and GI reflexes

66
Q

describe how a reflex occurs

A

reflex is generated in the spinal cord, opposed muscle sets in limbs cause flexion or extension, spinal cord inhibits one set and and stimulates the other to cause withdrawal. In crossed extensor, opposite signals in different limbs causes one to flex and one to extend

67
Q

what does the parasympathetic system do

A

stimulates secretions from the salivary glands, nose and constricts pupils. reduces cardiovascular and respiratory activity, reduces heart rate and constricts airways. increases gastrointestinal activity, secretion, motility, glucose storage and bladder contractions

68
Q

what effects does the sympathetic system have

A

increases heart rate, blood pressure, respiration, inhibits gastrointestinal system