muscles physiology; building of muscle organ - cells, tissue, organ and muscle contraction process and regulation

Question 1

4 functions of muscular tissue

Answer 1

producing body movement s
stabilising body positions
movement of substances within the body
producing heat

Question 2

5 properties of muscle tissue

Answer 2

excitability 
conductivity 
contractility 
extensibility 
elasticity

Question 3

Muscle tissue.
what does it consist of?
what 3 types are they?

Answer 3

elongated cells called muscle fibres or myocytes that are modified for contraction using ATP as energy

skeletal
cardiac
smooth

Question 4

what are the 5 components of the connective tissue of the muscle? EPETA

Answer 4

Epimysium
perimysium
endomysium
tendons and aponeurosis

Question 5

Nerve and blood supply.
what are muscles innervated by?
each muscle fibre is in contact with one or more capillaries. what do capillaries do?

Answer 5

somatic motor neurons

supply oxygen and nutrients and remove heat and waste products

Question 6

sarcoplasm.
2 structure
2 function

Answer 6

located within the cell
contains glycogen, myoglobin and calcium

provide shape to cell
hold organelles in place

Question 7

sarcoplasmic reticulum (SR) 
1 structure 
1  function

Answer 7

fluid filled system of membranous sacs

sotres Ca2+

Question 8

myofibrils
2 structure
1 functions

Answer 8

small, thread links structure in sarcoplasm
extend entire length of muscle cell

contractile organelle

Question 9

myofilaments
2 structure
1 function

Answer 9

small protein structures arranges in sarcomeres
thick - myosin. thin - actin

contraction

Question 10

myofibrils composed of 3 types of muscle proteins. what are they? 2 examples

Answer 10

contractile - myosin and actin

regulatory - troponin and tropomyosin

structural - Titian and myosin

Question 11

contractile proteins.
myosin and actin
2 structure each
1 function

Answer 11

myosin

• main component of thick filament
• shaped like 2 golf clubs twisted together

actin

• main component of thin filament
• contains myosin binding site

generate force during contraction

Question 12

regulatory proteins
tropomyosin
troponin

2 structure each
1 function

Answer 12

tropomyosin

• covers myosin in binding site of actin molecules
• strands held in place by troponin molecules

Troponin

• complex of 3 proteins
• lies within the groove between actin filaments

help switch contraction process on and off

Question 13

what are 3 structural proteins?

Answer 13

Titin
dystrophin
myomesin and nebulin

Question 14

sarcomere (basic functional unit of myofibril)

components include 4 things. what are they?

Answer 14

Z disc

bands

h zone

m line

Question 15

z disc (component of sarcomere)

1 structure
1 function

Answer 15

narrow, plate shaped region of dense protein material

act as anchoring points for thin filaments

Question 16

bands (component of sacromere)

where are they found? what patterns do they create?

Answer 16

areas where thick and thin filaments overlap and create interlocking patterns

I band (thin filaments)

A band (both thick and thin filaments0

Question 17

H zone (component of sarcomere)

where is it found? what does it contain?

Answer 17

A band

only contains thick filaments

Question 18

M line
1 structure
1 function

Answer 18

centre of A band

attachment site for thick filaments

Question 19

explain 7 steps of sliding filament mechanism

Answer 19

myosin heads attach to and walk along thin filaments

thin filaments pulled towards M line

thin filaments slide inwards meeting at centre of sarcomere

z discs come together

sarcomere shortens

muscle fibre shortens

entire muscle shortens

Question 20

what are the 4 steps at the ONSET contraction cycle?

Answer 20

SR releases Ca2+ into sarcoplasm

Ca2+ binds troponin

troponin moves tropomyosin away from binding sites on actin

initiates contraction cycle

Question 21

contraction cycle consists of 4 steps. what are they?

Answer 21

ATP hydrolysis

formation of cross bridge

power stroke

detachment of myosin and actin

Question 22

Neuromuscular junction (NMJ). 
What is it called? What two things does it allow to communicate?

Answer 22

Synapse

somatic motor neuron and skeletal muscle fibre / cell

Question 23

Motor end plate.

what region is it?

Answer 23

sarcolemma opposite synaptic end bulb

Question 24

Muscle action potential

4 steps

Answer 24

release of ACh

activate of ACh receptors

production of MAP

termination of ACH activity

Question 25

relaxation cycle

2 steps

Answer 25

degradation of ACh

sequestration of Ca+2