More on muscle :) Flashcards
1
Q
there are 2 categories of individual fibre types, name them.
A
Fast twitch and Slow twitch
2
Q
Name the fibre that is called a slow fibre.
A
Type I
3
Q
Type I are slow-______ fibres and slow-______ fibres.
A
twitch, oxidative
4
Q
Type I fibres have large amounts of ________.
A
mitochondria
5
Q
Type I fibres have a high _____ concentration.
A
myoglobin
6
Q
Name the 2 types of fast fibres.
A
Type IIb and Type IIa.
7
Q
Type IIb are fast-_____ fibres and fast-_____ fibres.
A
twitch, glycolytic
8
Q
Type IIb fibres are _____ in diameter.
A
diameter
9
Q
Type IIa are called _____ fibres.
A
intermediate
10
Q
Type IIa are _____-oxidative fibres.
A
fast
11
Q
What is Type IIa described as?
A
A hybrid of type I and type IIb, eg. in between them :)
12
Q
What fibre types will power athletes and sprinters have a high percentage of?
A
they will have a high % of fast fibres.
13
Q
______ athletes and ____ runners will have a high % of slow fibres.
A
endurance, distance
14
Q
Non-athletes have ____% slow and ____% fast fibres.
A
50, 50
15
Q
What size are Type I fibres?
A
small
16
Q
what colour are type I fibres?
A
red
17
Q
myoglobin brings _____ to muscles.
A
oxygen
18
Q
Type IIa are _____ in size and are _____ in colour.
A
intermediate, pink
19
Q
What is the myoglobin and mitochondrial content of IIa fibres?
A
Medium for both :)
20
Q
What colour are IIb fibres and why?
A
White as they have low myoglobin concentration.
21
Q
Type IIb fibres have low ______ content.
A
mitochondrial.
22
Q
The resting tension in a muscle is called muscle ______.
A
tone
23
Q
Name a sensory unit associated with a tendon that is responsible for preventing damage to the associated muscle.
A
Golgi tendon organ
24
Q
Muscle tone is controlled by the sensory ______ ______, which measures muscle stretch.
A
muscle spindle
25
Why is muscle tone important?
it is important for generating reflexes,
maintaining posture and balance,
and controlling proper function of other organ systems.
26
Name the 2 muscle contraction types.
Isotonic contraction and Isometric contraction
27
What does isotonic contraction do?
It changes skeletal muscle length
28
What does isotonic contraction result in?
Motion
29
What happens if muscle tension is greater than the load?
The muscle shortens (concentric contraction)
30
What happens if muscle tension is less than load?
the muscle lengthens (eccentric contraction)
31
_____ contraction is when the muscle shortens to 70% of its original length.
Concentric
32
_____ contraction is when the muscle lengthens/elongates to 140% of its original length.
eccentric
33
Raising a weight during a bicep curl is an example of____ contraction.
concentric
34
Lowering a weight during a bicep curl is an example of ______ contraction.
eccentric
35
What is isometric contraction?
The skeletal muscle develops tension but is prevented from changing length.
36
What happens to the length of the muscle during isometric contraction?
It stays the same.
37
_____ and _____ of contraction are inversely related.
load, speed.
38
The heavier the load (resistance) on a muscle the ______ it takes for shortening to begin.
longer
39
If there is a heavier the load, the less the muscle will ____.
shorten
40
What is a muscle twitch?
A contraction as the result of a single stimulus.
41
Name the 3 periods of muscle contraction/relaxation.
Latent period
contraction period
relaxation period
42
How long does the latent period last for?
2/3 m/secs
43
During contraction, what is developed?
Tension
44
The ___ period lasts 15 m/s.
contraction
45
how long does the relaxation period last?
25 m/s
46
Why is there always a latent period?
As the muscle has to overcome lots of resistance.
47
In the muscle twitch diagram right between contraction and relaxation is the highest point on the graph, what is this known as?
Peak Tension
48
The _____ shows differences in tension over time for a twitch in different ____ muscles.
myogram, skeletal
49
The best length-tension relationship is referred to as the muscle's what?
Optimum Resting Length
50
If the sarcomere is too small in length, what will happen?
There will be no room for sliding filament to have any effect so no tension will be produced.
51
If the sarcomere is too long what will happen?
There will be no interaction between filaments and no tension will be produced.
52
the _____ _______ length is 75%-130% of the optimal length.
normal sarcomere
53
1.2 micrometres- 3.6 micrometres is known as a sarcomere's ______ _______.
operating range.
54
Name the 3 areas affecting force regulation in muscles.
- The type and number of motor units recruited
- Initial muscle length
- Frequency of stimulation
55
If there are more motor units there will be a _____ ______.
greater force
56
If there are ______ motor units there will be a greater force.
fast
57
What (in terms of initial muscle length) produces the greatest amount of tension?
Optimum Overlap
58
The nature of the _____ _____ neural ______ affects force regulation.
motor unit, stimulation
59
The ____ of stimulation affects force regulation.
frequency
60
Name the 3 types of muscle frequencies that you can get.
Simple twitches, summation then tetanus.
61
As we increase the frequency then the muscle won't have as much time to ______.
recover
62
If the stimulus is not that frequent, ____ _____ will occur.
simple twitches
63
When the stimulus becomes slightly more frequent this will cause _______ and an increase in _____.
summation, force
64
A very frequent stimulus results in high force, this is known as ______. But the muscles will get tired and then force will drop to nothing if overworked :)
tetanus
65
Name the 2 receptors in muscle.
Muscle spindle and Golgi Tendon Organ
66
What do muscle spindles detect?
(Dynamic and static) changes in muscle length
67
___ reflexes are involved with muscle spindles.
stretch
68
Stretch on muscle causes _____ ______.
reflex contraction
69
What does the Golgi tendon organ monitor?
They monitor tension developed in muscle.
70
If the Golgi tendon organ detects a change what happens?
The loop system kicks in.
71
What does the Golgi tendon organ prevent?
It prevents damage during excessive force generation
72
Golgi tendon organ- stimulation results in reflex ________ of muscle.
relaxation
73
We "spot" people at the gym due to this reflex _____ of muscle if a change in tension is detected.
relaxation
74
What is muscle fatigue?
When a muscle can no longer perform at the required level of activity.
75
When a muscle fatigues what is there a depletion in?
There's a depletion of metabolic reserves.
76
During muscle fatigue there is a decline in ____ within the muscle fibre due to ______ _____ build up.
pH, lactic acid
77
Why do you get a sense of weariness when your muscles fatigue?
Due to low blood pH
78
____ ______ can lead to damage to the sarcolemma or sarcoplasmic reticulum.
Muscle Fatigue
79
A pathological condition can be premature muscle fatigue, what can this cause?
heart problems and blood loss etc.
80
What is muscle atrophy?
The reduction in muscle fibre size, tone and power.
81
What causes muscle atrophy?
Lack of activity (or loss of neural innervation)
82
Sedentary lifestyle, bed rest and spinal cord injury can result in what?
Muscle Atrophy
83
What is muscle hypertrophy?
Muscle fibre increases in diameter (aka. gains) ;)
84
What causes muscle hypertrophy?
repeated, exhaustive stimulation- due to training
85
In hypertrophy what remains the same?
The number of muscle fibres remain the same, just the size increases
86
What would cause an increase in mitochondria, glycolytic enzymes and larger glycogen reserves?
Muscle hypertrophy
87
The process of contraction involves firstly the ___ ______ of ________.
neural stimulation, sarcolemma
88
What does neural stimulation of sarcolemma then cause?
It causes excitation-contraction coupling
89
The interaction between thick and thin filaments is known as _____ ______ _________.
muscle fibre contraction
90
What does contraction of muscle produce?
Tension/Force production
