Physiology

Question 1

three types of muscle

Answer 1

skeletal, cardiac, smooth

Question 2

striated muscle

Answer 2

cardiac and skeletal

Question 3

unstriated muscle

Answer 3

smooth muscle

Question 4

how is striation visualised under a microscope

Answer 4

alternating dark bands (myosin) and light bands (actin)

Question 5

voluntary muscles innervated by somatic nervous system

Answer 5

skeletal

Question 6

involuntary muscles innervated by ANS

Answer 6

cardiac and smooth

Question 7

where and when is calcium released from

Answer 7

lateral sacs of sarcoplasmic reticulum when surface action potential spreads down transverse t tubules

Question 8

what is a motor unit

Answer 8

single alpha motor neuron and all the skeletal muscle fibres it innervates

Question 9

do muscles which serve for fine movement have more or fewer fibres per motor unit?

Answer 9

fewer

Question 10

levels of muscle organisation

Answer 10

muscle - muscle fibre - myofibril - sarcomere

Question 11

light appearance in myofibril

Answer 11

actin

Question 12

dark appearance in myofibril

Answer 12

myosin

Question 13

what are the functional units of muscle

Answer 13

sarcomeres

Question 14

what is the functional unit of any organ

Answer 14

the smallest component capable of performing all the functions of that organ

Question 15

What is an A band

Answer 15

thick filaments along with portions of thin filaments that overlap in both ends of thick filaments

Question 16

What is an H zone

Answer 16

lighter area within middle of A band where thin filaments don’t reach

Question 17

What is an M line

Answer 17

extends vertically down middle of A band within the centre of H zone

Question 18

What is an I band

Answer 18

consists of remaining portion of thin filaments that do not project in A band

Question 19

what produces muscle tension

Answer 19

sliding of actin on myosin

Question 20

factors determining gradation of skeletal muscle

Answer 20

number of muscle fibres contracting within the muscle and tension developed by each contracting muscle fibre

Question 21

Prolonged muscle contraction resulting from many APs in a short time

Answer 21

tetanus

Question 22

can cardiac muscle be tetanised?

Answer 22

no

Question 23

name for a single contraction in skeletal muscle

Answer 23

twitch

Question 24

two types of skeletal muscle contraction

Answer 24

isotonic and isometric

Question 25

what is isotonic contraction used for

Answer 25

body movements and moving objects | muscle tension constant when muscle length changes

Question 26

what is isometric contraction used for

Answer 26

supporting objects in fixed positions and maintaining body posture muscle tension develops at constant muscle length

Question 27

Knee jerk

Answer 27

spinal segment L3/4 | femoral nerve

Question 28

Ankle Jerk

Answer 28

S1/2 | tibial nerve

Question 29

Biceps jerk

Answer 29

C5/6 | musculocutaneous nerve

Question 30

brachioradialis jerk

Answer 30

C5/6 | radial nerve

Question 31

Triceps jerk

Answer 31

C6/7 | radial nerve

Question 32

what are the sensory receptors for the stretch reflex

Answer 32

muscle spindles/intrafusal fibres

Question 33

Type 1 fibres

Answer 33

slow oxidative | prolonged relatively low-work aerobic activities - posture, walking

Question 34

Type 2a fibres

Answer 34

fast oxidative | aerobic and anaerobic metabolism and useful in prolonged relatively moderate work activities - jogging

Question 35

Type 2x fibres

Answer 35

fast glycolytic | anaerobic metabolism, used for short term high intensity activities like jumping

Question 36

stages of synaptic transmission

Answer 36

``` synthesis storage release receptor activation transmitter inactivation ```

Question 37

neurotransmitter at NMJ

Answer 37

acetylcholine

Question 38

end plate potential (epp)

Answer 38

depolarisation of skeletal muscle fibres as a result of neurotransmitter binding to postsynaptic membrane in NMJ

Question 39

electrical response to one quantum of transmitter

Answer 39

miniature end plate potential (mepp)

Question 40

auto-antibodies in neuromyotonia (Isaac's syndrome)

Answer 40

voltage activated potassium channels in the motor neurone

Question 41

auto-antibodies in Lambert-Eaton myesthenic syndrome

Answer 41

voltage activated calcium channels in motor neurone terminal

Question 42

auto-antibodies in myasthenia Gravis

Answer 42

nicotinic ACh receptors in the endplate

Question 43

drugs for neuromyotonia

Answer 43

anti-convulsants

Question 44

drugs for Lambert Eaton syndrome

Answer 44

anticholinesterases and potassium channel blockers

Question 45

drugs for myasthenia gravis

Answer 45

anticholinesterases in diagnosis and pyridostigimine for long term treatment along with immunosuppressants

Question 46

three main types of joint

Answer 46

fibrous (synarthrosis) cartilaginous (amphiarthrosis) synovial (diarthrosis)

Question 47

why does synovial fluid have a high viscosity?

Answer 47

due to presence of hyaluronic acid

Question 48

functions of synovial fluid (5)

Answer 48

lubrication facilitates joint movement minimises wear and tear aids in nutrition of articular cartilage supplies chondrocytes with O2 and nutrients and removes CO2 and waste

Question 49

structure of ECM of articular cartilage

Answer 49

water, collagen and proteoglycans

Question 50

function of water in ECM

Answer 50

maintains resiliency of tissue and contributes to nutrition and lubrication system

Question 51

function of collagen in ECM

Answer 51

tensile stiffness and strength

Question 52

function of proteoglycan in ECM

Answer 52

responsible for compressive properties associated with load bearing

Question 53

how do chondrocytes receive nutrients and oxygen?

Answer 53

via synovial fluid because articular cartilage is avascular

Question 54

catabolic factors of cartilage matrix turnover

Answer 54

stimulate proteolytic enzymes and inhibit proteoglycan synthesis e.g. TNFa and IL1

Question 55

anabolic factors of cartilage matrix turnover

Answer 55

stimulate proteoglycan synthesis and counteract effects of IL1 e.g. TGFb and IGF1

Question 56

markers of cartilage breakdown

Answer 56

serum and synovial keratin sulphate and type 2 collagen

Question 57

three types of pain

Answer 57

nociceptive inflammatory pathological

Question 58

adaptive pain

Answer 58

nociceptive | inflammatory

Question 59

maladaptive pain

Answer 59

pathological

Question 60

pain responsible for withdrawal reflex

Answer 60

nociceptive

Question 61

pain which is activated by the immune system

Answer 61

inflammatory

Question 62

pain which results from abnormal nervous system function

Answer 62

pathological

Question 63

subtypes of nociceptor

Answer 63

A-delta fibres | C fibres

Question 64

A-delta fibres

Answer 64

thinly myelinated mechanical/thermal nociceptors mediate fast/first pain

Question 65

C fibres

Answer 65

unmyelinated | second or slow pain

Question 66

subset of C fibres

Answer 66

peptidergic polymodal nociceptors | afferent and efferent

Question 67

function of afferent C fibres

Answer 67

transmit nociceptive information from CNS via release of glutamate and peptides within dorsal horn

Question 68

function of efferent C fibres

Answer 68

release pro-inflammatory mediators from peripheral terminals - neurogenic inflammation

Question 69

Two peptides involved in neurogenic inflammation

Answer 69

SP and CGRP

Question 70

function of SP

Answer 70

causes vasodilation and extravastion of plasma proteins and a release of histamine from mast cells and sensitisation of surrounding nociceptors

Question 71

function of CGRP

Answer 71

induces vasodilation

Question 72

primary neurotransmitter in dorsal horn

Answer 72

glutamate

Question 73

in which laminae of Rexed do nociceptive c and a-delta fibres terminate

Answer 73

I and II

Question 74

Cells receiving A-beta fibres are

Answer 74

proprioceptive

Question 75

two major nociceptive tracts

Answer 75

spinothalamic and spinoreticular tracts

Question 76

what does spinothalamic tract detect

Answer 76

where is the pain coming from and how bad is it

Question 77

what does spinoreticular tract detect

Answer 77

autonomic responses to pain - emotional side, how bad is it etc. largely transmits slow C fibre pain