Plant and Animal Responses Flashcards
(118 cards)
1
Q
2 types of cells that make up the NS?
A
Neurons & glial cells
2
Q
Neurons?
A
transmit via APs
3
Q
Glial cells?
A
help nutrients pass into neurons, help balance the conc of ions, myelination (Schwann cells), phagocytosis, may be involved in stimulating the formation of new synapses
4
Q
2 branches of the NS?
A
Central nervous system & peripheral nervous system
5
Q
2 branches of the peripheral NS?
A
somatic NS and autonomic NS
6
Q
Autonomic NS?
A
• Anything that happens w/o thought = automatic
• input: internal muscles
output: SM & glands
7
Q
2 branches of autonomic NS?
A
- Sympathetic NS
* Parasympathetic NS
8
Q
Peripheral NS?
A
all neurons outside CNS
9
Q
Somatic NS?
A
- All to skeletal NS
* conscious control
10
Q
CNS?
A
= brain and SC
• majority of this is intermediate neurons
• includes meninges
11
Q
meninges?
A
- made of 3 layers
- protect CNS from pathogens and mechanical damage
- secretes CSF (specialised TF)
- The meninges are the connective tissue coverings of the brain and SC
12
Q
Cerebro spinal fluid?
A
- specialised TF
* Fills spaces in brain and & SC and therefore acts as a shock absorbed, also provides nutrients and O2 to cells
13
Q
Gyri of the brain?
A
the ridges
14
Q
sulci=
A
the grooves
15
Q
-itis?
A
inflammation
16
Q
CNS?
A
- Mainly IN, short dendrites, as many as 200,000 synapses with neighbouring cells (role to integrate)
- synapses can be excitatory or inhibitory (prevents AP)
- SC is really just an extension of the brain, connects and runs down the spinal canal as far as the lumber region
17
Q
in the centre of the SC…
A
is CSF
18
Q
PNS?
A
- All of the neurons outside CNS
- contains all of the neurons that connect CNS to the rest of the body
- SN carry nerve impulses from receptors to CNS
- motor neurons which carry APs from CNS to effectors
- function of the PNS is to connect CNS to periphery of the body
19
Q
SN?
A
• Carry afferent APs from PNS ➡ CNS - sensory input
20
Q
motor output?
A
• MN carry efferent APs from CNS to effectors
21
Q
Autonomic NS?
A
- The Para NS and Sympa NS are antagonistic
- when one is inhibited, other is activated
- contains all motor neurons to internal organs
- controls all SM and cardiac muscl
- self adjusting
22
Q
cell bodies of MN are outside the?
A
CNS, unlike somatic which go all the way to the effector
23
Q
if a neuron goes outside,
A
look at cell body to determine if CNS or PNS
24
Q
Autonomic cell bodies?
A
- situated in autonomic ganglia
* all contain a preganglionic neuron which carries AP from CNS to ganglion
25
Sympathetic NS?
* Axons of preganglionic neuron leave ventral root
* synapse at the ganglia
* goes to all organs
* noradrenaline used
* some use ACh (sweat glands, some blood vessels)
* fight or flight
* all signals via spinal nerves which go to ganglions
26
fight or flight repsonse?
response to stress, causes release of adrenaline
27
parasympathetic and sympathetic are?
* antagonistic
| * when one is stimulated, other is inhibited
28
fight or flight?
* release of adrenaline
* ⬆resp, ⬆HR, ⬆BR
* contraction of radial muscles of the iris to dilate pupil
* relax urethera sphincter and relax anal sphincter
* constriction of arterioles in DS
* dilation of arterioles in skeletal muscles
* saliva production stopped to save water and energy
29
Parasympathetic NS?
* All nerve pathways are either at the top or base of the SC
* No Ganglion - synapse just before the effector organ
* most neurons leave at the top in a large nerve called the vagus nerve
* NT is Ach, usually inhibitory, but cab be excitatory
30
Rest and digest?
* stimulates digestive activity - peristalsis - SM contracting pushing things along
* salivary glands
* not a very sig effect
31
which muscles contract causing the pupil to constrict?
circular muscles
32
The reflex arc?
stimulus ➡ receptor ➡ SC not CNS ➡ Effector ➡ response
33
a reflex is?
involuntary, stereotyped response to a sensory stimulus - often a survival or protective response
34
the knee-jerk reflex?
* used by the body to maintain posture and balance, allowing us to remain balanced with little conscious thought
* pain receptors in the knee detect hammer
* send signals down a sensory neuron to CNS which enter CNS thru dorsal route
* MN activated wihin SC
* MN carries AP to effector down ventral route
* effector (flexor muscle) contracts
35
reflexes can be used ti?
diagnose issues with SC. Specific reflexes test spec spinal nerves
36
Brain?
• controls how we perceive, think, learn, remember e.g.
37
Gross structure of the brain?
* Hindbrain
* Midbrain
* Forebrain
38
Hindbrain?
Pons, medulla oblongata, cerebellum
39
Midbrain?
Brain stem in Midbrain and hindbrain
40
Forebrain?
* Cerebrum
* thalamus
* hypothalamus
41
cerebrum?
learning, memory, personality, conscious thought
42
cerebellum?
unconscious functions, posture and balance
43
hypothalamus?
regulator centre, temp, H2O - contains osmoreceptors
44
medulla oblongata?
controls autonomic NS, HR, breathing
45
pituitary gland?
hormones
46
5 main brain areas?
* cerebellum
* hypothalamus
* MO
* cerebrum
* pituitary gland
47
Cerebrum [detailed]
* largest part, covers rest of the brain, it's the visible surface of the brain
* reecives sensory info ➡relates this info to past exp➡ sends impulse down MN to effectors
* controls all voluntary responses & some involuntary
48
cerebrum has 2 hemispheres?
L&R - connected via corpus callosum
49
frontal lobe?
* part of cerebrum
| * most reasoning/ decision making
50
outer layer of cerebrum is known as?
cerebral cortex
51
why does the right side of the brain receive signals from the left side of the body?
• neurons cross over at the back of the brain
52
Cerebral cortex main areas?
* frontal lobe
* parietal lobe
* temporal lobes
* occipital lobe
53
frontal lobe?
intelligence, personality, thought
54
parietal lobe?
sensory and motor function
55
temporal lobe?
emotion/auditory
56
occipital lobe?
visual
57
3 main types of functional area in the CC?
1. sensory areas
2. association areas
3. motor areas
58
sensory areas?
receive APs from sense organs - input
59
association areas?
process and co-ordinate sensory input - form associations with prev. exps - processing
60
motor areas?
APs generated and sent to effectors - output
61
Sensory area, association areas, motor areas
* each sensory area receives info from receptor cells
* size of sensory area is dependent on the sense organ
* impulse then goes to association area (analysed)
* impulse sent to motor areas, which send impulse down a NM to effector
62
main area of motor function?
primary cortex just at the back of the frontal lobe
63
association areas are often found close to?
corresponding senory areas
64
cerebellum?
* does not initiate movement, just co-ordinates
* balance receptors in the ear signal
* tweaks by changing tones in muscles and tendons
* receives input from sensory areas
* outputs APs to motor areas to fine tune motor activity
65
pons?
* relays AP from forebrain to cerebellum
| * sleep, posture
66
hippocampus?
* short term ➡ long term memory
| * part of limbic system - emotions
67
hypothalamus?
* area of forebrain found just above PG
* links NS and ES thru PG
* produces releasing factors which cause the anterior pituitary to release hormones e.g. growth hormone
* contains receptors like osmoreceptors which cause neurosecretory cells to release hormones into capillaries of posterior pituitary
* responsible for thermoregulation, osmoregulation, hunger, thirst, fatigue
68
pituitary gland?
• consists of anterior and posterior pituitary
69
medulla oblongata?
* lower portion of the brain stem, just b4 SC
* responsible for autonomic functions lik BP and breathing
* contains cardiac centre = responsible for controlling HR
70
anterior pititary?
* neurosecretory cells secrete growth hormone releasing factor
* GHRF causes endocrine cells to secrete GH
71
Posterior pituitary?
* osmoreceptors detect low blood WP and activate neurosecretory cells
* neurosecretory cells secrete ADH
72
Neurons in CNS?
relay
73
Neurons in Peripheral NS?
SN & MN
74
Somatic NS
input from sense organs, output to skeletal muscles
75
Autonomic NS
input from internal receptors, output to SM and glands
76
Sympathetic NS NT?
noradrenaline
77
Parasympathetic NS NT?
Ach
78
Adrenaline release (somatic NS)
* Adrenal medulla releases adrenaline
* stimulated by envir stimulus
* adrenaline causes fight/ flight
* Amplification cascade caused by cAMP
79
Amplification cascade?
millions of glucose molecules made from glycogen instantaneously
80
Fight or flight response
* Respiration rate inc
* causes blood pH to decrease (carbonic acid dissociates)
* causing acidosis
* so rate of CO2 excretion must inc
* HR increases to inc CO2 delivery to lungs
* this would raise blood pH back to normal
81
Control of HR: Medulla contains
* cardio acceleratory centre
| * cardioinhibtory centre
82
cardioacceleratory centre is connected to SAN via?
accelerator nerve
83
cardioinhibitory centre is connected to SAN via?
vagus nerve
84
Baroreceptors?
* detect pressure changes in aorta and carotid arteries
* if pressure is high CI stimulated
* if low CA stimulated
85
Accelerator nerve?
increases HR
86
Vagus nerve?
decreases HR
87
The cardiac centre?
controls HR, contains CIC and CAC
88
What do chemoreceptors do?
* monitor blood pH
* Too high = CI stimulated
* too low = CA stimulated
89
If HR ⬇?
* BP and pH decrease
* detected by baroreceptors and chemoreceptors
* CAC activated
* APs move along accelerator nerve
* noradrenaline released at SAN
* HR ⬆, adrenaline sec ⬆
90
if HR is too ⬆?
* pH too high as CO2 excretion too high
* baroreceptors and chemoreceptors
* CIC activated, APs along vagus nerve
* ACh released at SAN
* HR and adrenaline secretion decreases
91
nervous and hormonal communication of HR is an e.g. of
negative feedback
92
Sarco =
flesh
93
What needs to occur before a muscle can contract?
myosin binding sites need to be exposed
94
NMJ?
a synapse between a MN and muscle fibre
95
Types of muscle?
skeletal, smooth, cardiac
96
Skeletal muscle?
* attaches skeleton
| * only contract w stim from MN
97
smooth muscle?
* arteries, bronchi, airways
* all BC other than capillaries
* any BV that is not attached to a skeleton
98
cardiac muscle?
heart
99
which types of muscle are striated?
skeletal and cardiac
100
what is a muscle fibre called?
syncytium
101
SM is ran entirely by _____ NS?
autonomic
102
When muscles contract?
end up exerting a force on the bone, so we end up pulling on body parts
103
Muscles in the upper arm?
* 2 main
* when the bicep contracts it pulls the radius and ulna towards the scapular bending the arm
* at the same time, the tricep muscle lengthens
* when the tricep contracts, the arm straightens - extensor muscle
* an antagonistic pair
* so we have controlled moment
104
muscles always work in ?
pairs
105
each muscle fibre?
lies parallel to one another
106
muscle fibres can ? but we can't make more muscle
swell
107
structure of a muscle fibre?
* lots of cells where the PM has broken down between them, leading to a giant multinucleated cell
* these syncytium are surrounded by a specialised plasma membrane called the sarcolemma
* many mitochondria
* lots of SER - called sarcoplasmic reticulum
108
longitudinal stripes in a muscle fibre are called ?
myofibrils. Around these are organelles pushed to the edges
109
what are the invaginations of the sarcolemma called?
T tubules
110
sarcoplasm?
cytoplasm of muscle cell- not v much
111
actin appearance on micrograph?
thin, appears lighter
112
A band ?
myosin + interlocking actin
113
I band?
actin only
114
H band ?
where there is only myosin - no actin
115
Z line to Z line
anchor of actin
116
M line ?
anchor of myosin
117
one complete unit/sarcomere ?
Z line to Z line
118
When muscles contract,
they slide over each other and get shorter - I band
