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Biology - Module 5 > Animal Responses > Flashcards

Animal Responses Flashcards

1
Q

what does the CNS consist of

A

brain / spinal cord

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2
Q

what does the PNS consist of

A

all neurones in body

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3
Q

split the nervous system by functional organisation

A

somatic and autonomic

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4
Q

what is the somatic nervous system

A

voluntary / conscious control

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5
Q

what is the autonomic nervous system

A

involuntary / subconscious control

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6
Q

what can you split autonomic nervous system into

A

parasympathetic and sympathetic

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7
Q

what is the sympathetic nervous system known as

A

fight or flight

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8
Q

what is the parasympathetic nervous system known as

A

rest and digest

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9
Q

sympathetic responses

A

increases heart rate

dilates airways

redirects blood flow to the muscles

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10
Q

where do the sympathetic branches originate from

A

middle of spinal column

thoracolumbar region

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11
Q

where are the ganglia located in the sympathetic branches

A

close to spinal cord

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12
Q

are the post ganglionic fibres long or short in the sympathetic branches

A

long

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13
Q

does the sympathetic nervous system have few or many postganglionic branches and whats the purpose of this

A

many postganglionic branches

multiple organs activated at once

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14
Q

what is the neurotransmitter for sympathetic

A

norepinephrine

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15
Q

parasympathetic responses

A

slows down the heart rate

constricts airways

promotes digestion

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16
Q

where do the parasympathetic branches originate from

A

from higher up spinal column

craniosacral region

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17
Q

where are the ganglia located in the parasympathetic branches

A

close to target organs

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18
Q

are the post ganglionic fibres long or short in the parasympathetic branches

A

short

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19
Q

does the parasympathetic nervous system have few or many postganglionic branches and whats the purpose of this

A

few - targeted organs activated at a time

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20
Q

what is the neurotransmitter for parasympathetic

A

acetylcholine

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21
Q

summarise all the information on sympathetic + parasympathetic on two diagrams

A
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22
Q

salivary glands - sympathetic and parasympathetic stimulation

A

sympathetic - saliva production reduced

parasympathetic - saliva production increased

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23
Q

lung - sympathetic and parasympathetic stimulation

A

sympathetic - bronchiole muscle relaxed (more airflow)

parasympathetic - bronchiole muscle contracted

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24
Q

kidney - sympathetic and parasympathetic stimulation

A

sympathetic - decreased urine secretion

parasympathetic - increased urine secretion

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25
Q

stomach - sympathetic and parasympathetic stimulation

A

sympathetic - peristalsis reduced

parasympathetic - gastric juice secreted

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26
Q

small intestine - sympathetic and parasympathetic stimulation

A

sympathetic - peristalsis reduced

parasympathetic - digestion increased

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27
Q

what are ganglia + its function

A

collection of nerve cell bodies found outside CNS

a site of integration + relay for signals in PNS

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28
Q

are the pre and postganglionic neurones in the autonomic system myelinated

(from CNS to effector)

A

the preganglionic neurones are lightly myelinated

the postganglionic neurones are unmyelinated

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29
Q

what is the brain protected by

A

skull

protective membrane - meninges

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30
Q

what does the cerebrum control

A

voluntary actions

learning / memory / personality + conscious thought

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31
Q

what is the structure of the cerebrum

A
  • highly convoluted
  • split into left + right hemispheres which are joined by the corpus callosum (band of fibres)
  • the outer layer is the cerebral cortex
  • has sensory + motor areas
  • has white + grey matter
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32
Q

why is the cerebrum being highly convoluted significant

A

increases its SA

+ therefore capacity for complex activity

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33
Q

thickness of the cerebral cortex

A

2-4mm thick

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34
Q

function of the cerebral cortex

A

carries out most sophisticated processes

  • reasoning + decision making
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35
Q

structure of the sensory area in the cerebrum

A

size of sensory area – proportional to relative number of receptor cells present in that body part

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36
Q

function of the sensory area in the cerebrum

A

receives info from receptor cells in sense organs

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37
Q

where does the impulse go after the sensory area in cerebrum

A

passed to association areas – analysed + acted upon

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38
Q

where does the impulse go after the association area in cerebrum

A

motor areas

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39
Q

structure of the motor area in the cerebrum

A

size of motor area

– proportional to relative number of motor endings in it

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40
Q

function of the motor area in the cerebrum

A

main area that controls movement

– primary motor complex in back of frontal lobe

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41
Q

what is special about the base of the cerebrum

A

impulses from left + right side of body cross

e.g – inputs from eye pass to visual area in occipital lobe

impulses from right side of field of vision in each eye – sent to visual cortex in left hemisphere

easy to judge distance + perspective

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42
Q

where is grey matter found

A

in the cerebral cortex

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43
Q

what does grey matter contain + why is it grey

A

contains neurone cell bodies / dendrites / synapses

grey – abundance of cell bodies + lack of myelin sheath

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44
Q

function of grey matter

A

involved in processing + integrating sensory info

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45
Q

structure of grey matter and its significance

A

highly convoluted

increase SA – more neurones – more complex cognitive behaviours

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46
Q

where is white matter found

A

beneath grey matter

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47
Q

what does white matter contain

A

myelinated axons

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48
Q

function of white matter

A

forms nerve tracts – connect different regions of brain + allow communication

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49
Q

example of white matter

A

corpus callosum

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50
Q

what does the cerebellum control

A

controls unconscious functions

e.g. posture / balance / non-voluntary muscular movement

also involved in adjusting movements based on feedback to improve accuracy + efficiency over time – (motor learning)

  • essentially compares intended movement with actual movement
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51
Q

where does the cerebellum receive + relay impulses to and from

A

receives info from organs of balance in ears + tone of muscles / tendons

relays this info to motor area of cerebral cortex

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52
Q

structure of medulla oblongata

A

has many regulatory centres used in automatic control

  • cardiac centre
  • vasomotor centre
  • respiratory centre
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53
Q

function of cardiac centre in medulla oblongata

A

controls heart rate

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54
Q

function of vasomotor centre in medulla oblongata

A

controls blood pressure by controlling the contraction of smooth muscles in arteriole walls

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55
Q

function of respiratory centre in medulla oblongata

A

controls breathing rate

contains an inspiratory centre and an expiratory centre

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56
Q

overall functions of medulla oblongata

A

control reflex activities

–breathing rate + heart rate / swallowing / peristalsis / coughing

serves as a relay station for info passing from spinal cord to higher brain centres

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57
Q

what is the hypothalamus

A

main controlling region for autonomic nervous system

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58
Q

sections of hypothalamus

A

has parasympathetic + sympathetic centre

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59
Q

what does the hypothalamus control

A

controls complex patterns of behaviour = feeding / sleeping / aggression

monitors composition of blood plasma – conc of water + glucose

produces hormones as an endocrine gland

controls temp + water balance – negative feedback

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60
Q

where is the pituitary gland located

A

base of hypothalamus

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61
Q

structure of pituitary gland

A

anterior pituitary - front

posterior pituitary - back

connected by thin stalk

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62
Q

function of anterior pituitary gland

A

produces 6 hormones that regulate growth + reproduction + metabolism

e.g. FSH

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63
Q

function of posterior pituitary gland

A

stores + releases hormones produced by hypothalamus

e.g. ADH / oxytocin

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64
Q

what is the pituitary gland controlled by

A

controlled by hypothalamus through hormones

65
Q

describe the reflex arc

A

receptor – detects stimulus + creates action potential in sensory neurone

sensory neurone – carries impulse to spinal cord

relay neurone – connects sensory + motor neurone in spinal cord / brain

motor neurone – carries impulse to effector

66
Q

what is the spinal cord

A

column of nervous tissue running up back

67
Q

what is the spinal cord protected by

68
Q

draw a diagram of the spinal cord and draw the direction of impulse from the receptor to the effector

69
Q

what type of reflex is the knee-jerk reflex

A

spinal reflex

neural circuit only goes into spinal cord not brain

70
Q

describe the knee jerk reflex

A

legs tapped at patella (below kneecap) + stretches patellar tendon

stretch receptor generates action potential

passed via sensory neurones to spinal cord

relay neurone passes action potential to motor neurones

travels to the extensor muscle

quadriceps on top of thigh to contract

at same time – relay neurone inhibits motor neurone of the flexor muscle – it relaxes

contraction AND relaxation – antagonistic – cause leg to kick

71
Q

receptor for knee jerk reflex

A

stretch receptor in quadriceps muscle

72
Q

coordinator of knee jerk reflex

A

spinal cord

73
Q

effector of knee jerk reflex

A

extensor muscle

quadriceps contract

74
Q

purpose of knee jerk reflex

A

used to maintain posture + balance

75
Q

advantage of knee jerk reflex not passing through brain

A

synapses delay impulse

quicker overall

76
Q

what type of reflex is the blinking reflex

A

cranial reflex

passes through cranial nerve in brain stem // medulla

77
Q

stimulus examples for blinking reflex

A

cornea drying

being touched

hear sounds greater than 40-60dB

bright light
= protect lens + retina
= optical reflex

78
Q

describe the blinking reflex

A

stimulus causes action potential to be generated in the trigeminal nerve (receptor)

passed on via sensory neurone to the medulla

passed via motor neurones to the effector

= muscle lowers upper eyelid

= + other muscle helps pull eyelid inwards

response – eyelids close

79
Q

blinking reflex receptor

A

trigeminal nerve

80
Q

blinking reflex coordinator

81
Q

blinking reflex effector

A

multiple

  • superior levator palpebrae muscle lowers upper eyelid
  • orbicularis oculi helps pull eyelid inwards
82
Q

what does the blinking reflex indicate

A

lower brain stem functioning

83
Q

why are reflexes important for survival

A

avoid damage or reduce severity of damage

84
Q

how do reflexes increase chance of survival

A
  • being involuntary response
    = decision making regions not involved
    = prevents brain from being overloaded with situations where response is same
  • not having to be learnt
    = present at birth + immediate protection
  • Being very fast
    = Arc very short – only 1 or 2 synapses
    = Synapses delay response
85
Q

how is the flight or fight response coordinated

A

Threat detected by autonomic nervous system

Hypothalamus communicates with sympathetic nervous system + adrenal-cortical system

Sympathetic – uses neuronal connections

Adrenal – cortical system – uses hormones

86
Q

draw out a diagram for the coordination of responses for the fight or flight response

A

CRF – peptide hormone

87
Q

physical responses + their purposes for fight or flight

88
Q

main function of adrenaline in fight or flight

A

trigger liver cells to undergo glycogenolysis

= increase respiration

89
Q

what type of hormone is adrenaline

A

non steroid hormone

cant pass through membranes

90
Q

effects of adrenaline
(5)

A

stimulates muscle in iris to contract = pupils dilate

increases diameter of bronchioles by relaxing smooth muscle – increase airflow to alveoli

vasoconstriction – decrease amount of blood to gut

vasodilation – increase blood to muscles / brain

breakdown of glycogen to glucose in liver cells

91
Q

mechanism of how adrenaline increases blood glucose concentration

A

binds to receptors on liver cell

forms adrenaline-receptor complex

causes adenylyl cyclase to change shape = activated enzyme

catalyses ATP to cyclic AMP – secondary messenger

cAMP activates protein kinase enzymes – by binding to them

protein kinase phosphorylates other enzymes

catalyse break down of glycogen to glucose = glycogenolysis

92
Q

what nervous system is the heart rate controlled by

A

controlled by autonomic nervous system

93
Q

how is heart rate controlled by autonomic nervous system

A

cardio regulatory centre in medulla

= acceleratory centre - speed up
= inhibitory centre - slow down

94
Q

does the acceleratory centre use the sympathetic or parasympathetic nervous system to speed up

A

sympathetic

95
Q

does the inhibitory centre use the sympathetic or parasympathetic nervous system to slow down

A

parasympathetic

96
Q

what are the acceleratory + inhibitory centres activated by

A

baroreceptors

chemoreceptors

97
Q

how do baroreceptors activate the acceleratory + inhibitory centres

A

if blood pressure high

impulses sent to inhibitory centre in medulla

impulses along parasympathetic to SAN

98
Q

where are baroreceptors found

A

aorta

vena cava

carotid arteries

99
Q

how do chemoreceptors activate the acceleratory + inhibitory centres

A

detect changes in chemicals

e.g. carbon dioxide = by changes in pH

100
Q

describe what happens when carbon dioxide conc gets too high + low and what that activates

A

if carbon dioxide increases, pH decreases
=more carbon dioxide in blood
=more carbonic acid

increase frequency of impulses to medulla + trigger acceleratory centre

blood flow quicker to lungs to increase exhalation

if carbon dioxide decreases = pH rises

detected by chemoreceptors in walls of carotid arteries + aorta

results in reduction of frequency of nerve impulses sent to medulla

reduces frequency of impulses to SAN

heart rate back to normal

101
Q

describe how the acceleratory centre in medulla increases heart rate

A

when centre activated – impulses sent along sympathetic neurones ( accelerator nerve) to SAN

neurotransmitter - noradrenaline secreted at synapse with SAN

increases permeability of SAN cell membrane to sodium ions / calcium ions

influx of ions – enhances depolarisation

causes SAN to increase frequency of electrical waves

increased heart rate

102
Q

describe how the inhibitory centre decreases heart rate

A

when activated – impulses sent along parasympathetic neurones ( along vagus nerve ) to SAN

acetylcholine secreted with SAN

binds to receptors on SAN cell

increases permeability to potassium ions

efflux of potassium ions / hyperpolarise = slower heart rate

causes SAN to reduce frequency

reduces elevated heart rate back to resting state

103
Q

put all together in diagram - from stimulus (increase + decrease in carbon dioxide) to response (change in heart rate)

104
Q

what are the three types of muscle tissue

A

skeletal muscle

cardiac muscle

smooth muscle

105
Q

what is the bulk of muscle tissue

A

skeletal muscle tissue

106
Q

what is skeletal muscle responsible for

107
Q

where is smooth muscle found

A

walls of hollow organs = stomach + bladder

walls of blood vessels + digestive tract

108
Q

state the

  • fibre appearance
  • control
  • arrangement
  • contraction speed
  • length of contraction

for skeletal muscle

A
  • striated
  • conscious control
  • regularly arranged so muscle contracts in one direction
  • rapid speed
  • short length of contraction
109
Q

state the

  • fibre appearance
  • control
  • arrangement
  • contraction speed
  • length of contraction

for cardiac muscle

A
  • specialised striated
  • involuntary control
  • cells branch + interconnect resulting in simultaneous contraction
  • intermediate speed
  • intermediate length
110
Q

state the

  • fibre appearance
  • control
  • arrangement
  • contraction speed
  • length of contraction

for smooth muscle

A
  • non striated
  • involuntary control
  • no regular arrangement - cells can contract in different directions
  • slow speed
  • can remain contracted for a relatively long time
111
Q

structure of cardiac muscle

A
  • shows striations but fainter than skeletal muscle
  • fibres are branched + uninucleated
112
Q

structure of smooth muscle

A
  • shows no cross striations (non-striated)
  • fibres are spindle shaped + uninucleated
113
Q

which is cardiac skeletal + smooth

114
Q

plasma membrane of muscle

A

sarcolemma

115
Q

cytoplasm of muscle

A

sarcoplasm

116
Q

endoplasmic reticulum of muscle

A

sarcoplasmic reticulum

117
Q

what is a sarcomere

A

functioning unit of myofibril

118
Q

describe the structure of skeletal muscle

A

muscle fibres are long + multinucleated (strength)

T tubules - parts of sarcolemma fold inwards

lots of mitochondria + sarcoplasmic reticulum

119
Q

why are skeletal muscle fibres long + multinucleated

A

formed from many embryonic muscle cells fusing together

120
Q

how are skeletal muscles strong

A

long fibres from many muscle cells

junctions between adjacent cells are point of weakness

121
Q

purpose of t tubules

A

helps spread electrical impulse throughout sarcoplasm

ensures whole fibre contracts at same time

122
Q

structure of myofibrils

A

each muscle fibre has many myofibrils

long + cylindrical + made of protein

lined up in parallel for max force when contracting

made up of two protein filaments - actin + myosin

123
Q

what is actin

A

thinner filament

two strands twisted around eachother

124
Q

what is myosin

A

thicker filament

long / rod-shaped fibres with bulbous heads that project to one side

125
Q

structure of a muscle fibre

126
Q

zoom into a muscle

A

bone

tendon

many muscle fibres

many myofibrils

actin + myosin

127
Q

describe the structure of a myofibril

A

I band – isotopic bands
(only actin - light)

A band – anisotropic bands
(myosin + actin overlap - dark)

H zone
(only myosin)

Z line
(centre of I band)

M line
(centre of H zone)

128
Q

how to measure a sarcomere

A

difference between two z bands

129
Q

draw out a myofibril structure

130
Q

how to identify skeletal muscle

A

Individual muscle fibres
= Long + thin
= Multinucleated
= Crossed with regular pattern of fine lines

Highly structured arrangement of sarcomeres

Streaks of connective + adipose tissue

Capillaries running in-between fibres

131
Q

describe the features of fast fibres - skeletal

  • speed
  • amount of Ca 2+
  • type of respiration
  • level of activity
  • fatigue
  • colour
  • storage
  • exampe
A

Contract rapidly

myosin heads bind + unbind from the actin-binding sites 5 times faster

need large amounts of calcium ions = forming more cross bridges

Rely on anaerobic respiration

Short bursts of high-intensity activity

fatigue quickly from lactate produced

Pale – low levels of myoglobin + blood vessels

Store creatinine phosphate – rapidly make ATP from ADP

E.g. - eyelids

132
Q

describe the features of slow fibres - skeletal

  • speed
  • power
  • activity
  • respiration
  • fatigue
  • colour
  • example
A

Contract slower

Less powerful but over longer period

Endurance

Aerobic respiration

Do not fatigue easily

Red - Denser network of capillaries + High amounts of myoglobin + mitochondria

e.g. Human back + calf muscles – contract for long periods of time to keep skeleton erect when standing

133
Q

compare slow and fast fibres - skeletal

  • contraction time
  • capillaries
  • respiration
  • mitochondria
  • calcium ions
  • storage
  • fatigue
134
Q

describe the sliding filament model

A

myosin heads pull actin inwards towards centre of sarcomere

sliding causes Z lines to come together

I bands shorten

A band stays same

( Myosin filaments have NOT shortened just overlap more )

H band narrows

Sarcomeres shorten

135
Q

describe the structure of myosin

A

Globular heads

On head – binding site for ATP/ADP and actin

Tails of several hundred myosin molecules – aligned to form myosin filament

136
Q

describe what happens at the neuromuscular junction - up until sarcoplasmic reticulum

A

Action potential arrives at neuromuscular junction

Stimulates calcium ion channels to open on presynaptic membrane

Calcium ions diffuse into synaptic knob

Causes snare proteins to contract

Causes vesicles containing acetylcholine to be released via exocytosis

Acetylcholine bind to receptors on postsynaptic membrane – sarcolemma

Causes opening of sodium ion channels – influx of sodium ions

Depolarises sarcolemma

Travels down t tubules into the sarcolemma + sarcoplasmic reticulum

Stimulates calcium ion channels to open

Calcium ion travel down conc gradient into the sarcoplasm

137
Q

what is a neuromuscular junction

A

Point where a motor neurone and a skeletal fibre meet

138
Q

what is a motor unit

A

All of the muscle fibres supplied by single motor neurone

139
Q

what happens to the acetylcholine once it has caused a conformational change + opened sodium channels

A

Broken down by acetylcholinesterase into choline + ethanoic acid

diffuse back into neurone to make acetylcholine

140
Q

describe the mechanism of muscle contraction

what happens after the calcium ions have been released into the sarcoplasm?

A

Calcium ions binds to troponin – causes a change in shape

Pulls on tropomyosin – moves away from actin-myosin binding site

Charge difference between myosin head + binding site causes head to be attracted to site

Forms actin-myosin cross bridge

Force of binding causes release of ADP and Pi molecule from myosin head

As myosin head in high energy state + now no molecules holding back – flexes forward

Pulls actin filament along = POWER STROKE

ATP molecule attaches to myosin head – conformational change

Causes head to pull away from binding site + break cross link

Calcium ions attach to head + activates ATPase activity of myosin

Hydrolyses ATP to ADP + phosphate ion – releases energy

Myosin head now in high energy state + can attach at another binding site when calcium ions bind to THAT NEW troponin

141
Q

which protein is blocking the actin-myosin binding site

A

tropomyosin

142
Q

when the muscle fibre is depolarised which ions are secreted from sarcoplasmic reticulum and where do they bind to

A

calcium ions

troponin

143
Q

what causes the tropomyosin to pull away from the binding site

A

the change in shape of the troponin

when the calcium ions bind to it

144
Q

the attachment of myosin causes what change in the myosin head

A

causes ADP + Pi to be released

145
Q

what does the release of ADP + Pi cause

A

the myosin head to flex forward

146
Q

after the power stroke - what causes the detachment of the myosin head from the binding site

A

ATP binding to myosin head

147
Q

what causes myosin head to return to original high energy state

A

hydrolysis of ATP into ADP + Pi

releases energy

148
Q

what happens to move the tropomyosin back into its original position of blocking the binding site

A

the lack of a calcium ion

action potential stopped being generated

149
Q

summarise muscle contraction

150
Q

what does the hydrolysis of ATP provide energy for

A

for movement of myosin head

and active transport of calcium ions back into tubules

151
Q

energy supply during contraction

A

aerobic respiration

anaerobic respiration

creatinine phosphate

152
Q

what is creatine phosphate

A

chemical stored in muscle fibres

153
Q

how does creatinine phosphate provide energy for muscle contraction

A

Provide phosphate ion to rapidly convert ADP to ATP

154
Q

write the equation for the use of creatinine phosphate to provide energy

155
Q

what enzyme catalysis this reaction

A

creatine phosphokinase

156
Q

what is the emergency store for aerobic respiration in muscles

A

myoglobin

Single chain polypeptide

157
Q

why is myoglobin a good emergency store

A

Very high affinity for oxygen – only release oxygen at very low partial pressures

158
Q

limitation of phosphocreatine

A

limited amount

only provides extra ATP for shirt bursts

Biology - Module 5 (8 decks)

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