Muscle Flashcards

1
Q

Define bone

A

Strong and hard, made of bone cells which are fixed firmly in a matrix of collagen and calcium salts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Define cartilage

A

Tissue, hard but flexible sketetal tissue that often act as a shock absorber and prevent wear in joints

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

2 types of cartilage

A

Hyaline cartilage
- found at the end of the bones

White fibrous cartilage
Densely packed collagen in the matrix
—> great tensile strength but is less flexible

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Define tendons

A

Inelastic white fibrous tissue made up of collagen fibre
MUSCLE TO BONE

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Define ligament

A

Most elastic tissue which forms joint capsule
(JOINS BONE TOGETHER)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Define synovial fluid

A

Fluid which lubricates the most mobile joints
- act as a lubricant
- prevent wear and tear of the cartilage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Define Antagonistic pairs

A

Muscle work which work in opposition to each other pulling in opposite direction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Properties of smooth muscle

A

Involuntary control

Not striped under the microscope
—> muscle in the gut, blood vessel

Contract and fatigue slowly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Properties cardiac muscle

A

Only found in the heart

Involuntary control

Striated under the microscope (appears stripy)

The fibres are joined by special cross connection

Contract spontaneously

Doesnt get fatigue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Define sacromere

A

Basic unit of muscle structure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Define sarcoplasm

A

The cytoplasm of muscle cell
-contain many mitochondria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Function of sarcoplasmic reticulum

A

Endoplasmic recticulum found in sacromere

  • stores and release calcium ion
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Define myofibrils

A

A very long contracting fibre in skeletal muscle cells

Lying parallel to each other

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Slow twitch is used for what activity

A

Maintain posture and during long periods of activity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is fast twitch muscle used for

A

Rapid brief activity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Does slow twitch contain more myoglobin

A

Contains more myoglobin and rich blood supply
—> the extra myoglobin can release oxygen to enable continued aerobic respiration (release much more ATP)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Does fast twitch contain more or less myoglobin

A

Less myoglobin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Does slow twitch contain lots of mitochondria

A

More mitochondria
-maintain their activity without needing to respire anaerobically for any length of time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Does fast twitch contain lots of mitochondria

A

Less mitochondria and fewer blood vessels
-often perform anaerobic respiration

20
Q

Slow twitch muscle fibre…

A

Which contracts and fatigues slowly

21
Q

Fast twitch muscle fibre …

A

Contract very rapidly and strongly and fatigue quickly

22
Q

Slow twitch contain less

A

Less glycogen stores

Less creatine phosphate

23
Q

Fast twitch muscle fibre

A

Contains lots of rich glycogen stores which can be converted to glucose for both aerobic and anaerobic respiration

Contain high level of creatine phosphate which can be used to convert ATP to ADP

24
Q

Through training the muscle what changes

A

The number of muscle fibre doesn’t change but the size and type of fibre can change

25
Q

What is actin made up of

A

Made up of two chain of actin monomers joined together like a beads of necklace

26
Q

What does the actin do

A

Troponin: protein molecules attached to tropomyosin changes shape due to the binding of calcium ions leading to a conformational shape change

Pulling in the tropomyosin and revealing the myosin binding site on the actin strands

In relaxed state tropomyosin covers the myosin binding site

27
Q

What’s myosin made up of

A

Two long polypeptide chains twisted together

28
Q

Sliding filament theory

A

When action potential reaches a muscle causes a response from impulse down motor neurone to neuromuscular junction

Causing the sarcoplasmic reticulum to release calcium ions

Calcium ions bind to the binding site causing a conformational change

Troponin moves and pulls the attached tropomyosin exposing the myosin binding site on the actin strand

Myosin head binds to myosin binding site on actin forming a cross bridge

Myosin head binds to actin; myosin changes shape by bends forward moving the actin : ADP+ Pi released from myosin head

Free ATP bind to the head causing another shape change in the myosin so the binding of the head to the actin strand is broken

Activating ATPase in the myosin head, which also needs calcium ions to work

ATP is hydrolysis providing the energy to return the myosin head to its original position with ADP and Pi

Myosin head move back to the original position and cycle repeats

Sarcoplasmic recticulum sucks all calcium ion back up calcium pumped back via active transport

29
Q

Describe the role of calcium ions in the contraction of skeletal muscle

A

1) calcium ions released in response to nervous stimulation of the muscle set up contreaction of sacromere

2)calcium ion binds to troponin changing the shape of the molecules
-this changes the shape of troponin so the pull the tropomyosin this moves the tropomyosin away from the myosin binding site with the myosin head

3) calcium ions is needed for action of ATPase enzyme in the myosin heads, which enables the heads to return to their resting position

30
Q

.

A
31
Q

How is the heartbeat controlled

A

1) the sinoatrial node established a wave of electrical excitation (depolarization) which causes the atria to starting contracting. This initiate the heartbeat

2) excitation also spreads to another area AVN (atrioventricular node)

3)the AVN is excited as result of the SAN but it produces a slight delay before the wave of depolarization passes into the BUNDLE OF HIS(this make sure that the atria stop contracting before the ventricle starts)

4) the bundle of his into two branches and carries the wave of excitation on into the purkyne tissue

5) the purkyne tissue consist of conducting fibre that penetrate down the septum, spreading around the ventricle

6) as depolarization travels through the tissue it starts the contraction of the ventricles starting at the bottom and so squeezing blood out of the heart

32
Q

Formula for cardiac output

A

Cardiac volume x heart rate

33
Q

What does the sympathetic nervous system do

A

Excitatory
— noradrenaline will be used as the neurotransmitters—> to stimulate SAn

34
Q

What does the parasympathetic system do to the heart

A

Inhibitory
— acetylcholine will be used as neurotransmitters—> to inhibits SAN

35
Q

What is the role of baroreceptor and where is it found

A

Aortic and carotid bodies
They are stimulated by changes in blood pressure

36
Q

What does the baroreceptor have in common with control of heart rate when adrenaline is released

A

1) adrenaline causes the blood vessel dilate (vasodilation) thus causing the blood pressure to reduce

2) causing a reduction of stimulation of baroreceptor

3) cardiovascular control centre sends the impulse along the sympathetic nervous system to stimulate heart

4) this increases the heart rate and blood pressure again by constricting the blood vessel

37
Q

What does the baroreceptor have in common with control of heart rate when exercise stop

A

1) when excerise stops, blood pressure in the arteries increases as the heart continues to pump harder

2) the baroreceptor is stimulated and stretched

3) sending more sensory nerve impulses through the control centre which send impulses through the parasympathetic system to slow down the heart rate and blood vessel to be wider

38
Q

What does chemoreceptors found and what is it stimulated by

A

Found in medulla oblongata and aortic and carotid bodies

Stimulated by levels of carbon dioxide and oxygen and blood pH

39
Q

Process of high blood pressure

A

Detected by baroreceptor which send impulse to cardiovascular control centre

It sends impulse along the sympathetic neurone which secrete the neurotransmitters noradrenaline
—> noradrenaline binds to receptor on SAN causing it to fire more frequently

Heart rate slow down and blood pressure decrease back to normal

40
Q

Process of high O2/Low CO2/high pH levels

A

Detected by chemoreceptors which sends to cardiovascular control centre

It sends impulses along the parasympathetic neurones which secrete the neurotransmitters acetylcholine
-acetylcholine bind to receptor on SAN causing it to fire less frequently

Heart rate slow down and O2 and pH level return to normal

41
Q

When there is an increases in carbon dioxide in the blood

A

1) carbon dioxide levels goes up this decreases the pH level

2) detected by the carotid and aortic chemoreceptors

3) they send impulses along sensory neurone to the cardiovascular control centre in the oblongata

4) thus, increase the number of impulses travelling down the sympathetic nerve to the heart

5)this result in an increased heart rate, increasing the blood flow to the lungs and so more carbon dioxide is removed from the blood

42
Q

What happens when carbon dioxide level Low in the blood

A

1) carbon dioxide level is Low and the blood pH increases

2) this is detected by carotid and aortic chemoreceptors

3)the chemoreceptors respond by reducing the number of impulse send to the cardiovascular control center

4) this then reduces the number of impulses along the parasympathetic nervous system

5) decreases the heart rate

6)decreased the blood flow to the lungs

43
Q

Where is adrenaline released from

A

Adrenal medulla when in fight or flight mode

44
Q

Process of adrenaline

A

1) adrenaline is transported around the body in the blood stream

2) it will bind to receptor on the target organ (example:SAN)

3)increase the frequency of excitation

4)increase the heart rate to supply blood to the muscle cell at a faster rate

5) more blood more oxygen and glucose that reaches the muscle cell which in turn increases the rate of aerobic respiration

6) this releases mor energy that will be used during the response to the stressful or dangerous situation
4)

45
Q

How does adrenaline affect the cardiovascular control centre

A

Stimulate the cardiovascular control centre in the medulla oblongata

This increases the impulse travelling along the sympathetic neurones affecting the heart furthering speeding up the heart rate