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MBChB1 Phase 1 > Week 8 > Flashcards

Week 8 Flashcards

1
Q

Nervous system functionS?

A
  • communication: between areas of the body
  • behviour: personality by frontal lobe
  • regulation: bresthing, HR, movement, temperature
  • stores information: memories
  • sensation: pain, touvh, feelings
  • emotions
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2
Q

what is the central nervous system composed of?

A

brain and spinal cord

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3
Q

what is the peripheral nervous system composed of?

A

spinal and cranial nerves

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4
Q

how many spinal nerves are there?

A

31 pairs

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5
Q

how many pairs of cranial nerves are there?
where do they come from?
where do they supply?

A

12
brain and brainstem
head and neck structures bar vagus nerve

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6
Q

what does somatic mean?

A

cell of the body, not germ line cell

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7
Q

what does visceral mean?

A

internal organs in main cavities of body

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8
Q

what does afferent mean?

A

arrives into spinal cord and brain

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9
Q

why does efferent mean?

A

exits brain and spinal cord

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10
Q

what does motor mean?

A

supplies muscle

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11
Q

what does autonomic nervous system mean?

A

involuntary part of body functions

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12
Q

what are somatic efferents supplying?

A

skeletal muscle

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13
Q

what do visceral efferents supply? difference between them and other neuronal pathways?

A

smooth muscle, glands, cardiac muscle
2 neurons in pathway, usually 1

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14
Q

what do longitudinal fissure seperqte?

A

2 cerebral hemispheres

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15
Q

what are the 2 layers of brain matter?

A

outer grey matter, inner white matter

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16
Q

what are gyri vs sulci? purpose?

A

gyri - brain ridges, stick out
sulci - spaces between grooves
increases surface area

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17
Q

when does brain folding happen?

A

embryological development

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18
Q

structure and function of brainstem?

A

midbrain, pons and medulla
breathing and HR control

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19
Q

what is brain coning?

A

swelling in brain presses on brainstem and impacts respiratory and cardiac systems

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20
Q

cerebellum fucntion?

A

controls movement and coordination

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21
Q

what is the telencephalon?

A

cerebrum

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22
Q

what is the diencephalon?

A

thalamus, hypothalamus

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23
Q

thalamus function?

A

relay station of sensory/motor systems
regulates sleep, consiousness, awakeness

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24
Q

hypothalamus function?

A

regulates endocrine system via pituatry gland
thermoregulation

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25
Q

what is the forebrain?

A

telencephalon and diencephalon

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26
Q

what is the mesencephalon, function?

A

midbrain
vision, hearing, motor function, arousal

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27
Q

what is the hindbrain or rhombencephalon?

A

part of developing brain

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28
Q

function of frontal lobe?

A

executive functions
long term memory, speech, movement, personality

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29
Q

what is the parietal lobe function?

A

sensory integration, language interpretation, spatial/visual perception

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30
Q

occipital lobe function?

A

visual processing - colour/light

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31
Q

temporal lobe function?

A

auditory cortex, memory, understanding language

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32
Q

function of cell body in neuron?

A

contains nucleus/mitochondria
interprets information around it via dendrites

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33
Q

function of dendrites in neurons?

A

take information from periphery and communicate with nerves around it

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34
Q

function of axons in neurons?

A

conducting portion

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35
Q

function of myelin sheath in neuron, what makes it? structure?

A

encases neuron, allows faster propogation of nerve impulses
produced by schwann cells/oligodendrocytes
made iof fat

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36
Q

function of node of ranvier?

A

between myelin sheaths
allows rapid transmission of nerve impulses

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37
Q

function of axon terminals?

A

allows communication with other axon terminals

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38
Q

function of astrocytes? how?

A

nutrient supply to neurons in CNS
link to blood vessels
also form blood brain barrier
structural support

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39
Q

function of microglia?

A

defence role (phagocytic)

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40
Q

function of ependymal cells?

A

produces CSF and circulate it

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41
Q

function of oligodendrocytes?

A

neuronal support
myelin formation in CNS

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42
Q

function of schwann cells?

A

neuronal support
myelin formation in PNS

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43
Q

what cells surrpund central canal?

A

ependymal cells

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44
Q

function of corpus callosum? what does crossing of fibres mean?

A

links cerebral hemispheres
crossing meand R brain controls left body, L brain controls R body

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45
Q

what does FAST stand for?

A

F - face drooping
A - arm weakness
S - speech difficulty
T - time to call emergency services
used in strokes

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46
Q

areas of glasgow coma sclae?

A

eye opening -4
verbal response - 5
motor response - 6

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47
Q

what is the conus medullaris?

A

lower end of spinal cord at L1/2

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48
Q

what is the cauda equina? where found?

A

nerve rootlets at L2-5
sits in space called lumbar cistem, formed by subarachnoid spaces from conus medullarys to S2

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49
Q

where can CSF be extracted?

A

subarachnoid space in cauda equina

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50
Q

Where does afferent sensory information from brain enter first in spinal cord?

A

dorsal root ganglion, then dorsal horn

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51
Q

where are aautonomic efferent nuclei found? function?

A

lateral grey horn
mediate sympathetic nervous system

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52
Q

how do efferent signals get to muscles?

A

via ventral root

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53
Q

what are meninges? 3 layers?

A

3 layers wrapping rounf brain and spinal cord
dura, arachnoid, pia

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54
Q

structure of dura mater?

A

thick membran made of dense irregular connective tissue
2 layers - periosteal, meningeal
joined directly to skull bone

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55
Q

structure of arachnoid mater?

A

…

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56
Q

structure of pia mater?

A

innermost layer
delicate
allows blood vessels to pass through annd nourish brain

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57
Q

where are falx cerebri found? function?

A

longitudinal fissure, prevents brain movement

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58
Q

how many different types of spinal nerves are there?

A

8 cervical
12 thoracic
5 lumbar
5 sacral
1 coccygeal

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59
Q

which axons are found in each spinal nerve?

A

sensory and motor axons

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60
Q

what are dermatomes?

A

individual region of skin supplied by sensory neurons

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61
Q

what are myotomes?

A

blocks of muscle supplied by motor axons

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62
Q

why doesnt C1 have a dermatome?

A

doesnt have dorsal root, only motor root supplying head/neck muscles

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63
Q

what are v1/v2 dermatomes associated with?

A

trigeminal nerve

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64
Q

function of dermatomes clinically?

A

helps locate whats wrong if theres pain in a certain area

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65
Q

structure of psudounipolar neuron?

A

1 extension from cell body splits into 2 branches - one goes to PNS, one to CNS

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66
Q

Structure of multipolar neuron? found in?

A

single axon and many dendrites, usually motor neurons

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67
Q

structure of autonomic multipolar neurons? what does it supply?

A

synapse between 2 neurons, supplies glands, heart, gut

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68
Q

name 12 cranial nerves and their functions.

A
  • olfactory: smell
  • optic: vision
  • oculomotor: eye movements
  • trochlear: eye movements
  • trigeminal: motor to muslces of mastication and general sensory to face
  • abducens: eye movements
  • facial: muscles of facial expresiion
  • vestibococchlear: hearing and balance
  • glossopharangeal: swallowing, taste
  • vagus: wandering nerve supplying heart, lungs, gut
  • spinal accessory: neck muscles
  • hypoglossal: tongue muscles
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69
Q

2 parts of somatic nervous system?

A

sensory and motor system

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70
Q

2 fibres of autonomic nervous system?

A

visceral afferent and visceral efferent

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71
Q

2 types of visceral efferent fibres?

A

sympathetic and parasympathetic

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72
Q

where are sympathetic fibres found?

A

T1-L2

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73
Q

where are parasymapthetic fibres found?

A

S2-S4

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74
Q

what do nociceptive fibres detect?

A

pain sensation

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75
Q

how many neurons are in the effector pathway of the autonomic nervous system?

A

2

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76
Q

what does caudal mean in regards to the brain?

A

below or towards the back

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77
Q

what does dorsal and ventral mean in the brain?

A

dorsal is above longitudinal axis of forebrain
ventral below

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78
Q

what does rostral mean in the brain?

A

towards the front

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79
Q

where are unipolar neurons usually found?

A

sensory neurons

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80
Q

where are bipolar neurons usually found?

A

interneurons

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81
Q

where are multipolar neurons usually found?

A

motorneuron/interneuron

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82
Q

where are pyramidal neurons usually found?

A

forebrain e.g. cerebral cortex

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83
Q

the dysfunction of which glial cell can cause multiple sclerosis?

A

oligodendrocytes

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84
Q

the dysfunction of which glial cell can cause guillan-barre syndrome?

A

schwann cell

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85
Q

what is a glioma? what is a glioblastoma?

A

glioma is brain tumor
glioblastoma i grade IV glioma. aggressive form

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86
Q

which cell types are found in grey matter?

A

cell bodies
dendrites
axon termini
glial cells e.g. astrocytes
blood vessels

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87
Q

which cell types are found in white mater?

A

myelinated axons
glial cells - oligodendrocytes
blood vessels

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88
Q

what is the deep lobe of the brain?

A

limbic lobe

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89
Q

which cranial nerves arise from the brainstem?

A

CN III - XII

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90
Q

which system has functions in the medulla?

A

autonomic nervous system

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91
Q

where are reflex centres found in the brain? what does this require?

A

medulla e.g. vomiting
nuclei

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92
Q

what is another name for grey matter?

A

cerebral cortex

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93
Q

what functions are in the prefrontal corteX?

A

cognition
personality
behaviour
mood

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94
Q

what happens if brocas area is damaged? where is this area?

A

speech impaired but can comprehend speech
towards front of brain between frontal and parietal lobe

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95
Q

what happens if wenickes area is damaged? where is this area?

A

fluent speech but no meaning, cant comprehend speech
towards back of brain between temporal and parietal lobes

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96
Q

what is contained in limbic system?

A

amygdala and hippocampus

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97
Q

function of amygdala?

A

emotions and emotional behaviour

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98
Q

function of hippocampus?

A

learnign and memory

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99
Q

function of basal ganglia?

A

controls movement

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100
Q

function of corpus callosum?

A

communication between brain parts

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101
Q

where is language production and comprehension usually in the brain?

A

left hemisphere

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102
Q

what happens if your brain is split down the corpus callosum?

A

cant verbally describe image shown in left visual field as fibres cross over between hemispheres in CC

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103
Q

what is the spinal cord an extension of?

A

brainstem

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104
Q

what spinal nerves control diaphragm?

A

C345 keep the diaphragm alive

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105
Q

which spinal nerves cotrol knee and foot movement

A

L3-S1

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106
Q

which spinal nerves are involved in sympathetic activity?

A

T1-12

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107
Q

which nerves are involved in parasympathetic activity?

A

Cranial nerves and S4

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108
Q

function of the filum terminale?

A

suspends spinal cord in CSF

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109
Q

what is the conus medullaris?

A

end of spinal cord

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110
Q

what are spinal cord tracts?

A

bundles of nerve fibres running up and down spinal cord

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111
Q

function of spinothalamic tract? ascending or descending?

A

ascending, sensory, pain and temperature

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112
Q

function of corticospinal tract? ascending or descending?

A

descending
motor
voluntary movement

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113
Q

what does decussate mean? when is it used?

A

cross over
spinal cord tracts

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114
Q

meaning of ipsilateral and contralateral in relation to spinal cord tracts?

A

ipsilateral: same side
contralateral: opposite side

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115
Q

What are partial spinal cord injuries? Where is function lost?

A

damage to specific spinal tracts
loss of function below level of injury
if tracts decussate below, lose function on contralateral side
if none, ipsilateral side

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116
Q

why do the 2 dura mater layers seperate?

A

to form venous sinuses

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117
Q

when does the epidural potential space occur?

A

when meningeal artieries supplying dura rupture, causes haematoma, space fills with blood

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118
Q

when does the subdural potential space occur?

A

when bridging veins connecting to venous sinuses rupture, causes haematoma, space fills with blood

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119
Q

what is within the subarachnoid space?

A

csf
cerebral arteries/veins
connective arachnoid trabeculae

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120
Q

what is different about the meninges at the spinal cord?

A

one layer of dura mater
epidural space contains fat and venous plexus

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121
Q

what is meningitis an inflammation of?

A

pia and arachnoid mater and subarachnoid space

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122
Q

which infections cause meningitis?

A

viral and bacterial

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123
Q

what is seen in a lumbar puncture when someone has meningitis?

A

increased WBCs in CSF +/- bacteria

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124
Q

where do you do a lumbar puncture?

A

between L4-5

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125
Q

Which parts of the brain does CSF fill?

A

ventricles and subarachnoid space

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126
Q

how much csf is there in total?

A

125-150ml

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127
Q

functions of CSF?

A

cushions brain against movement and own weight
provides stable chemical environment for brain e.g. electrolyte levels
nutrient and waste exchange between nervous tissue and blood

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128
Q

how might neurodegenerative disease be related to CSF?

A

reduced CSF turnover = metabolic waste buildup

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129
Q

what is the daily turnover of csf?

A

500ml/day

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130
Q

where is CSF produced?

A

chorid plexus - lateral and 4th ventricles

131
Q

what is circulation of CSF driven by?

A

new production

132
Q

what is caused by excess CSF levels?

A

hydrocephalus

133
Q

what is different in CSF compared to plasma?

A

few cells
lower protein
different electrolyte levels

134
Q

what is the blood brain barrier?

A

several features preventing harmful substances getting into brain and spinal cord from blood

135
Q

how do capillaries in nervous tissue act as a blood brain barrier?

A
  • tight junctions between endothelial cells restrict movement
  • thick continuous BM
  • astrocytes processes cover vessel
136
Q

how do ependymocytes act as a blood brain barrier, where do they line?

A

line ventricles and spinal canal
- tight junctions restrict movement

137
Q

which areas of the blood brain barrier have higher permeability?

A

area postrema in medulla: toxin detection for vomiting
pituatry gland in endocrine system secretes hormones

138
Q

what happens when the blood brain barrier is diseased?

A

toxins can get into CNS and cause problems

139
Q

functions of blood brain barrier?

A
  • keeps out toxins, pathogens etc.
  • stops fluctuation of ions, nutrient, metabolite concentrations in CNS
140
Q

what would happen if the blood brain barrier was defective and increased potassium leaked into the CNS?

A

it would affect nerve impulses

141
Q

what is the blood brain barrier permable to?

A
  • water, small lipophilic molecules, gases by diffusion
  • glucose, amino acids by active transport
142
Q

what exactly is a signal?

A

ion movement or movement of electrical charge

143
Q

examples of signals?

A

gap junctions between cardiac myocytes
nerve cells along cell membrane

144
Q

how quickly do neurons transmit signals? what does speed depend on?

A

up to 120m/s
type of neuron

145
Q

which system has slow signalling?

A

endocrine

146
Q

what is the longest neuron in the body?

A

base of spine to big toe

147
Q

what is an impulse/action potential?

A

wave of altered charge along nerve cell membrane that sweeps along axon

148
Q

what is the membrane potential maintained by?

A

ion pumps in plasma membrane

149
Q

whta is usually the electrical potential difference across neuron plasma membrane

A

-70mV

150
Q

when is an action potentual generated?

A

when nerve cell is stimulated

151
Q

what happens in an action potential?

A

depolarisation: voltage gated sodium channels open and flow into the cell, membrane potential increases
repolarisation: potassium channels open at 30 mV and flow out of the cell, sodium channels close
hyperpolarisation: potassium channels close, sodium channels reset and return to rest

152
Q

what is hyperpolarisation?

A

too many

153
Q

what is hyperpolarisation?

A

too many potassium leave cell so the cell becomes very negatuve

154
Q

how does the membrane return to resting potential after hyperpolarisation?

A

ion diffusion

155
Q

how is an impulse prevented from going backwards along a neruon?

A

refractory period

156
Q

what is a refractory period?

A

time immediately following AP when new AP cannot be initiated in same area of membrane

157
Q

what is the absolute refractory period?

A

sodium channels close and cannot be activated for short period of time

158
Q

what is the relative refractory period?

A

sodium channels could open but harder to reach ap due to hyperpolarisation

159
Q

which 4 ion channels are present in the hydrophobic membrane?

A

leakage, voltage ligand and mechanically gates

160
Q

what is the stimuli for opening leakage channels?

A

randomly opens

161
Q

what is the stimuli for opening voltage gated channels?

A

changes in membrane potential

162
Q

what is the stimuli for opening ligand gated channels?

A

specific ligand binding to receptor

163
Q

what is the stimuli for opening mechanically gated channels?

A

tension in the membrane

164
Q

what is the distribution of sodium and potassium ions at rest?

A

more sodium ions on outside of cell
more postassium ions on inside

165
Q

where does the sodium potassium pump get energy to pump ions across a conc gradient?

A

energy from the hydrolysis of ATP

166
Q

what happens in the sodium potassium pump?

A

3 sodium out, 2 potassium in

167
Q

which ion channels are open at rest? what does this do?

A

leakage channels for sodium and potassium
keeps resting potential at -70

168
Q

what membrane potential figure causes an AP?

A

-55mV

169
Q

what happens if the membrane does not reach -55mV?

A

sodium potassium pump restores membrane potnetial

170
Q

what is a graded potential?

A

small changes in membrane potential

171
Q

which inputs to dendrites starts an AP?

A

excitatory pre-synaptic potentials
inhibitory pre-synaptic potentials

172
Q

what do excitatory pre-synaptic potentials do?

A

increase chances of AP initiation

173
Q

what do inhibitory pre-synaptic potentials do?

A

decreases chances of AP initiation

174
Q

what is spatial summation?

A

summation of inputs from different areas of cell e.g. from different dendrites

175
Q

what is temporal summation?

A

input occurs multiple times from same dendrites, repeated inputs in short time = summation

176
Q

does Ap frequcny or magnitude vary?

A

ap frequcency varies
magnitude stays the same

177
Q

what is the signal intensity in a neuron caused by?

A

AP frequency

178
Q

what do APs cross at the end of a neuone?

A

synapse

179
Q

what is a signal reflex arc?

A

neural pathways containing multiple nerve cells such as relay neuron

180
Q

function of neurotransmitters in signalling?

A

can help transmit signal across a synapse

181
Q

when are neurotransmitters released, where do they bind?

A

when AP reaches pre-synaptic neuron termini
bind to receptors of post synaptic neuron

182
Q

which type of signal are neurotransmitters?

A

chemical

183
Q

which type of chemical signal can be excitatry or inhibitory?

A

neuotransmitters - promote/inhibit formation of AP in receiving neuron

184
Q

example of amino acid neurotransmitter?

A

glutamate: excitatory
gaba: inhibitory

185
Q

example of monoamine neurotransmitter?

A

dopamine, serotonin

186
Q

where is acetycholine derived from? function in signalling?

A

choline
neurotransmitter

187
Q

example of peptide neutrotransmitters?

A

substance P
endorphins

188
Q

which type of receptor is GABA-A?

A

ion channel

189
Q

what happens when GABA ligand binds to GAPA-A?

A

conformation change opens ion channel
ions flow along conc gradient
AP happens in pre synaptic neuron
triggers release of vesicles contianing GABA
diffuse actoss synapse and binds to gaba a

190
Q

what flows into the cell when GABA binds? what happens?

A

negative chlorine
hyperpolarisation

191
Q

which medcines use GABA and why?

A

benzodizepines, ethanol, some anaesthetic
inhibition of APs causes sedative action

192
Q

how is GABA switched off?

A

reuptake into presynaptic cell by transporters
enzymes degrade neurotransmitters

193
Q

which type of receptor is nAChR?

A

sodium ion channel receptor

194
Q

what happens when ACh binds to nAChR at neuromuscular junction?

A

sodium entry causes depolarisation of muscle cell membrane which intiates contraction

195
Q

how is ACh effects switched off?

A

acethylcholinsterase removes ACh

196
Q

what is the cause of myasthenia gravis?

A

muscle weakness:
autoimmune antibodies attach ACh receptors at neuromuscular junction

197
Q

treatment for myasthenia gravis?

A

AChE inhivitors enhances NMJ transmission

198
Q

what excatly is the heartbeat?

A

electrical impulse travels along heart tissue causes contraction of heart muscle via gap junctions

199
Q

which cells spread charge throughout the heart? which order? how?

A

purkinje fibres
atria first then ventricles
ions flow between adjacent myocytes via gap junctions

200
Q

which cells have the alpha globin gene?

A

all, only some make alpha globin protein through

201
Q

what is transcription?

A

turning DNA to RNA

202
Q

what is translation?

A

turning RNA to protein

203
Q

which RNA doesnt translate?

A

tRNA
rRNA
miR

204
Q

what is a genome?

A

sequence of all DNA in an organism

205
Q

what is a gene?

A

unit of inheritance, some code for proteins

206
Q

difference between exons and introns?

A

exons - excellent, keep in
introns, intruder, keep out

207
Q

what is the UTR?

A

untranslated region, end of transcript that doesnt get translated

208
Q

which way is rna translated?

A

5’ to 3’ end

209
Q

what is the cap addition site?

A

adds protective nucleotide to RNA

210
Q

what is PolyA addition site?

A

adds protective nucleotide to RNA

211
Q

3 steps of transcription?

A

initiation: RNA polymerase pulls DNA strands apart
Elongation: RNA gets longer forming transcription bubble
Termination: RNA synthesis stops

212
Q

what is splicing, what does this?

A

removes introns
spliceosome

213
Q

where is mRNA translates?

A

cytoplasm

214
Q

where do transcription factors bind and what do they do?

A

bind to short but specific DNA sequences
affect rate of transcription by turning genes on or off, activates or represses

215
Q

what are master regulators?

A

transcription factors determining how much protein will be made from a gene

216
Q

examples of transcription factors?

A

p53 and E2F
nuclear hormone receptors e.g. oestrogen/testosterone receptors

217
Q

where do steroids act on?

A

transcription factors

218
Q

how does RNA polymerase 2 bind to DNA as it cannot do it itself?

A

general/basal TFs act as a bridge between DNA and RNA polymerase

219
Q

where do transcription factors bind to?

A

TATA box and CAT box

220
Q

what is the promoter?

A

transcription factors bind here to influence how much protein is expressed

221
Q

what happens when the TATA box is muatted in beta globin gene promoter?

A

thalassaemia - severe anaemia

222
Q

what happens when the CCR5 promoter is mutated?

A

affects rate that HIV progresses to aids

223
Q

what happens when there are mutations in the factor IX promoter?

A

haemophilia b

224
Q

what happens when there are mutations in the LDLR promoter?

A

familial hypercholerolemia

225
Q

what stabilises the transcription intitiation complex?

A

TFs on upstream enhancer elements

226
Q

what can make it more or less likely to activate a promoter?

A

enhancer/silencer

227
Q

how is p53 an activator and repressor?

A

activates transcription of p21, cell cycle arrest and DNA repair
respressor of transcription of surviviv, apoptosis

228
Q

how is E2F an activator?

A

activates transcription of genes needed for S phase

229
Q

how is Oct-1 a repressor?

A

respresses transcription of TSH in all cells

230
Q

where is TSH transcribed?

A

thyrotrophs in pituatry

231
Q

what does snail repress?

A

e cdherin in epithelial cancers, less cell-cell adhesion, more inhasive ability

232
Q

what mutations are frequently found in enhancers or silencers?

A

single nucleotide polymorphisms

233
Q

what keeps DNA closed to TFs?

A

nucleosomes

234
Q

what are locus control regions?

A

super enhancers
open chromatin spanning several genes

235
Q

example of super enhancer?

A

globin genes
TF binds to globin LCR in erythrocytes
opens DNA of all globin genes
gene expression possible

236
Q

what happens when LCR are mutated? disease?

A

locus stays closed
globin expression very low
hispanic thalassaemia

237
Q

what is consititutive gene expression?

A

genes that are expressed in all cells all the time at the same levels
housekeeping genes: maintain basic cell function

238
Q

examples of housekeeping/constitutive genes?

A

beta-actin for microfilaments
ribosomal proteins
GAPDH in glycolysis
general/basal transcription factors

239
Q

what promoter do constitutive genes have?

A

constitutive promoter

240
Q

what are inducible genes?

A

genes only expressed in certain tissues or cells at certain times

241
Q

examples of inducible genes?

A

protein coding genes
cell specific: CD4,CD8, Collagen I and II, globin, myelin
time specific: cyclins, melatonin, inflammatory cytokines

242
Q

clinical significance of time specific expression?

A

teratoma, cancer, hereditary persistence of fetal hemoglobin

243
Q

what is splicing?

A

removal of introns by spliceosome

244
Q

what is an isoform?

A

different mRNAs from same gene

245
Q

what can affect splicing?

A

single nucleotide polymorphisms

246
Q

what happens when there is a snp in beta globin first intron?

A

thalassaemia

247
Q

what happens when dysstrophin is alernative spliced?

A

duchennes muscular dystropy

248
Q

what happens when cftr is alternative spliced?

A

modifies severity of cystic fubrosis

249
Q

what happens when tau is alternativrly spliced?

A

frontotemporal dementia with parkinsonism

250
Q

what are microRNAs? function?

A

short rna sequencecs
complementary binding to mRNA to initiate its destructuin
can reduce gene expression post translationally

251
Q

what are microRNAs involved in pathogenically?

A

cancer

252
Q

what is the genome?

A

sequence of all the DNA in an organism

253
Q

what is the transcriptome? what can it be used for?

A

all mRNAS in given tissue or cell at a given time
differentiate between diseases

254
Q

what is the proteome?

A

all the proteins in a cell/tissue/tumor

255
Q

what increases antibiotic resistance?

A

selection pressure from repeated exposure to antibiotics

256
Q

what folows the emergence of antibiotic resistance?

A

a novel agent

257
Q

how does clostridium difficile cause damage to the body?

A

lives in the gut and colonises the bowel where it releases toxins
can cause ibs

258
Q

what is the increased numbers of c diff cases linked to?

A

increased antibitotic resistance

259
Q

what is antibiotic stewardship?

A
  • reduce antibitoic consumption
  • restrict worst offender agents
    -promote logical antibioticc choices
  • limit co-lateral damage
260
Q

what is guided antibiotic therapy?

A
  • identifying cause of infection and selecting agent based on sensitivity testing
261
Q

what is empirical antibiotic therapy?

A

best educated guess therapy based on clinical acumen
when therapy cannot wait for culture

262
Q

what is prophylactic antibiotic therapy?

A

preventing infection before it begins

263
Q

which infections wuld you use guided therapy for?

A

mild ones that can wait a few days
cystitis, mild wound infecions

264
Q

which infections would you use empirical therapy for?

A

severe infection
sepsis/meningitis

265
Q

when would you use prophylactic therapy?

A

healthy people exposed to: surgery, injury, infected material
immunocompomised individuals: hiv, transplants, splenectomy

266
Q

what are the target effects of antibiotics?

A
  • highly toxic to bacteria causing infecion
  • penetrate body area affected by infection
  • limit release of toxins from bacteria
  • convenient administration
267
Q

what co-lateral damage should be limited with antibiotics?

A
  • non-toxic
  • limited effect on colonising bacteria
  • low potential for bacteria to escape treatmet through resistance
268
Q

what needs to be achieved with narrow spectrum/guidedtherapy antibiotics?

A
  • use antibiotic which has limited action to the bacteria causing infection
  • limit penetration to site of infection
  • cure patient with as little impact on colonisation and resistance as possibel
269
Q

what needs to be achieved with broad spectrum/empirical therapy antibiotics?

A
  • use antibiotic which has extensive action against ant bacteria which may be causing infection
  • need to penetrate broadly throughout the body
  • accept that impact on colonisation and resistance may be greater
270
Q

what do bactericidal antibiotics do to achieve sterilisation? what can this cause?

A

directly kill bacteria
release of toxins and inflammatory material

271
Q

how do bacteriostatic antibiotics work? what do they require to clear bacteria? what is this called?

A

suppress growth but dont directly sterilise infected site
requires additional factors to clear bacteria from immune system
immune mediated killing

272
Q

4 antibiotic targets?

A

cell wall
metabolism
DNA/RNA
ribosome

273
Q

why are penicillin good antibiotics?

A

rapidly kill bacteria
low toxicity

274
Q

how do penicilins/beta lactam antibiotics work?

A

insert beta lactam ring into peptidoglycan cell wall to inhibit cell wall synthesis
cell lysis will occur

275
Q

what can a penicillin allergy result in?

A

rash or anaphylaxis

276
Q

how many people report penicilin alergy compared to how many people actually have a penicillin allergy?

A

10 percent
1 percent

277
Q

why is penicillin allergy label associated with poorer clinical outcomes?

A

they are effective antibiotics in many diseases e.g. cancer and alternatives dont work as well

278
Q

name 3 beta lactam drugs? where do they target?

A

penicllin
cephalosporins
cerbapenems
cell wall

279
Q

where do vanomycin antibiotics work and what are they useful against? where do they target?

A

large molecule cannot penetrate gram negative cell wall so gram positive
useful against penicillin resistant drugs e.g. mrsa
cell wall

280
Q

what are doxycycline and clarithromycin effective against? where do they target?

A

intracellular pathogens as they are highly concentrated there
infections caused by both gram positive and negative organisms e.g. chest infections
ribosomes

281
Q

what are ciprofloxacin effective against? where do they target? issue with them?

A

broad spectrum
damage dna
resistance is now widespread

282
Q

what is trimethoprim used for? where do they target? problem?

A

non severe uti
target metabolism
resistance is widespread
first antibiotic

283
Q

what are antibiotics derived from?

A

micro organisms

284
Q

what are 3 primary mechanisms of resistance?

A

mutation of target site
inactivating enzymes
limmiting acces - reduced permability

285
Q

how can beta lactams be inactivated?

A

beta- lactamase destrosy beta lactam ring

286
Q

how can beta lactamases be overcpme?

A

beta lactamase inhibitors
beta lactamase stable drugs

287
Q

what is the somatic nervous system?

A

part of peripheral nervous system
carries motor and sensory information to CNS
part of body which you can control

288
Q

what is the autonomic nervous system?

A

part of nervous system controlled uncounsciously

289
Q

what are the two parts of the peripheral nervous system?

A

sympathetic and parasympathetic

290
Q

which part of peripheral nervous system is fight or flight?

A

sympathetic

291
Q

what is the origin of sympathetic output? exception?

A

thoracolumbar spinal cord
cervical ganglia - extension of sympathetic chain, supplies head and neck e.g. to dry mouth and dilate pupils

292
Q

what is the sympathetic neurotransmitter at the preganglionic synapse?

A

acetycholine

293
Q

what is the sympathetic neurotransmitter at the post ganglionic synapse?

A

noradrenaline

294
Q

what does the sympathetic nervous system do when it encounters a threat?

A

pupils dilate to see more
mouth dry to provide moisture in organs
adrenaline release from adrenal glands to speed up heart and increase contraction
inotropy: strength of heart contractions increase
chtonotropy: rate of cardiac contraction increases
vasodilation: in skeletal muscles so more oxygen delivered, in skin so heat is lost
reduced blood supply to gut to induce constipation
urinary/fluid retention
sweating

295
Q

what does the renal system do in symapthetic response?

A

vasocontriction - reduced blood supply to kidneys as you want blood in muscles
increased renin to promote further vasocontriction

296
Q

what is the post ganglionic neurotransmitter in sweat glands and deep muscle vessels?

A

acetycholine

297
Q

function of alpha 1 receptor?

A

arteriole constriction: causes increased blood pressure, increased flow around the body, more oxygen to blood vessels/organs

298
Q

function of alpha 2 receptor?

A

coronary/venous vasoconstriction

299
Q

function of beta 1 receptors?

A

increase heart rate and contractility of the heart

300
Q

function of beta 2 receptors?

A

smooth muscle relaxation:
uterus - so you dont give birth
gut - constipation
bladder - fluid retention
lungs- bronchodilation
eye - dilation
skeletal blood vessles - more o2 to muscles

301
Q

what happens when the parasympathetic nervous system is activated?

A

pupillary constriction to improve near vision
nasal engorgement - maximise sensory absoprtion
excess salivation to eat
increased gastric secretions and blood flow
slow heart rate
bronchoconstrition
urination/defecation

302
Q

origin of parasympathetic nervous systen?

A

craniosacral outflow

303
Q

where is parasymapthetic ganglia? where do they diffuse?

A

near site of action
vagus

304
Q

what are the ganglionic neurotransmitter in parasympatheric nervous system?

A

acethycholine pre and post

305
Q

where is sympathetic ganglia?

A

next to spinal cord

306
Q

what cranial and sacral nerves are the origins of parasympathetic nervous system?

A

c - 3,7,9,10
s - 2,3,4

307
Q

2 types of parasympathetic receptors?

A

muscarinic receptors
nicotinic receptors

308
Q

function of m2 receptor?

A

slow heart rate to normal rhythym

309
Q

function of m3 receptor?

A

increase salivary production
increase blood supply to gut
increase bladde contraction
constrict pupils

310
Q

function of muscarinic receptors antagonists?

A

reduce affect of ach on heart
increases heart rate

311
Q

what is the lung m3 receptor agonists?

A

tiotropium/ipratropium

312
Q

what is the bladder m3 receptor agonists?

A

oxybutinin

313
Q

what is the gut m3 receptor agonists?

A

mebervine

314
Q

what is the eyes m3 receptor agonists?

A

pilocarpine

315
Q

muscarinic receptors in brain?

A

m1
m4
m5

316
Q

what are n1 receptors involved with?

A

motor neurons

317
Q

what are n2 receptors involved with?

A

autonomic nervous system

318
Q

functions of the brain stem?

A

cranial nerve function
conduit function - connects brain to rest of body
integrative functions

319
Q

what does coning of the brain cause?

A

raised pressure
cerebellar tonsillar herniation
ischaemia of brainstem

320
Q

what can brain stem death cause?

A

paralysis/unconsiousness
apneoea
loss of cranial nerve function

321
Q

how can you test brain stem death?

A

known irreversible cortical death
excluson criteria met
unconscious, apneic

322
Q

the gene for which protein would be constitutively expressed?

A

translation initiation factor

323
Q

which gene would be repressed in a neuron?

A

keratin

324
Q

in which part of the cell is the splieosome found?

A

nucleus

MBChB1 Phase 1 (12 decks)

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