Muscles Flashcards

1
Q

How many muscles in body

A

400-500

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

Skeletal, smooth and cardiac muscle, voluntary or involuntary?

A

Skeletal- voluntary
Smooth-involuntary
Cardiac- involuntary

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

Prefix referring to muscle

A

Myo

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

Muscles are made of bundles of muscle fibers made of

A

Myofibrils

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

Myofibril bundles in muscle are made of

A

Myofilaments (actin and myosin)

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

The “__” lines make up the striations in skeletal muscles

A

“Z” lines

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

Actin and myosin are arranged in

A

Sacromeres

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

Which myofilament is thin, which is thick

A

Actin is thin, myosin is thick

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

How contraction happens

A

Actin and myosin interlock, shortening the sacromeres, myofibrils shorten, muscle fibers shorten

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

The the actin and myosin “unlock” and the muscle

A

Lengthens and relaxes

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

Proximal end of muscle is the _____

Distal end is the ______

A

Origin

Insertion

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

What causes flexion and extension in limbs

A

Contraction and relaxation of muscles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Nerves release a chemical messenger to send information to contract muscles. This messenger is called

A

Acetylcholine (Ach)

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

The acetylcholine sent by the nerves to the muscle cells does what

A

Stimulates sarcoptic (endoplasmic) reticulum of muscle cells to release calcium (Ca++) into cytoplasm

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

What Ca++ does when it is released by the sarcoptic reticulum

A

Ca++ exposes a binding site on the actin so that myosin can bind to it

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

Once actin and myosin bind, they need this to contract and shorten

A

ATP (energy)

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

When the brain says “stop contracting” the nerves stop releasing

A

Acetylcholine (Ach)

18
Q

The Ach that was released to cause the muscles to contract, gets broken down by ___________

A

Acetylcholinesterase

19
Q

When muscles are relaxing, where does the Ca++ go that was released

A

Gets collected back into the sarcoplasmic reticulum (ATP needed here too)

20
Q

Stiffness of death (when you die and your body stiffens)

A

Rigor Mortis

21
Q

Why rigor mortis occurs

A

Ca++ is released from SR after death Bc no ATP is keeping it there. Ca permanently binds to the actin

22
Q

Rigor mortis ends how long after death. Why

A

12-24 hours. The muscles start to break down

23
Q

Muscles breaking down after death is referred to as

A

Autolysis

24
Q

Exercising first uses _____ produces by aerobic respiration

A

ATP

25
Q

When oxygen runs out during exercise, what happens

A

Anaerobic respiration begins making ATP

26
Q

What causes muscles to hurt/ burn during exercise

A

The lactic acid produces by anaerobic respiration

27
Q

What multiple sclerosis does (MS)

A

Autoimmune disease that attacks the nerves that go to the muscles. They cannot bring signals to muscles properly, muscles don’t function normally

28
Q

What MS does to the nerves to make them not send signals correctly

A

Body attacks nerves, peels off some protective coating

Like fraying an electric cord

29
Q

How muscle paralysis occurs (through poison)

A

Poisons such as curare or botulism toxin block binding sites for Ach on muscle fiber (no Ach, no contractions)

30
Q

Examples of poisons used in darts or surgical drugs for paralysis

A

Curare botulism

31
Q

Why insecticide poising can cause spasms and seizure-like occurrences

A

Some insecticides block the activity of acetylcholinesterase. Ach is not broken down, muscles continue to contract even when brain says stop

32
Q

Indications of insecticide poisoning (like organophosphate poisoning)

A

Animal stuff/spasm/seizure, increased intestinal motility (diarrhea, vomiting), constricted pupils

33
Q

How to treat insecticide poisoning

A

Activated charcoal orally, a bath, injection of atropine

34
Q

What atropine does

A

Blocks the Ach binding sites on the muscles

35
Q

Hypocalcemia causes what in small breed dogs and cows

A

Dogs: Eclampsia
Cows: milk fever

36
Q

What hypocalcemia is

A

Deficient in Ca++ and muscles won’t work

37
Q

Signs of hypocalcemia in cows and dogs

A

Cows: cold, weak, go down to ground
Dogs: hot, stiff (shiver so much that temperature spikes)

38
Q

How to treat hypocalcemia

What happens if you do this too much

A

Treat with IV calcium and increased dietary calcium.

Too much CA++ can cause heart attack

39
Q

Hypertrophy

A

Increased size of muscles (weights, testosterone)

40
Q

Atrophy

A

Decrease in size of muscle (disuse, nerve/spinal cord injuries)

41
Q

Dystrophy

A

Degeneration of muscles

42
Q

Example of a dystrophy disease

A

Duchenne’s muscular dystrophy in humans. X-linked, affects 1 in 3600 boys