Muscles

Question 1

How many muscles in body

Answer 1

400-500

Question 2

Skeletal, smooth and cardiac muscle, voluntary or involuntary?

Answer 2

Skeletal- voluntary
Smooth-involuntary
Cardiac- involuntary

Question 3

Prefix referring to muscle

Answer 3

Myo

Question 4

Muscles are made of bundles of muscle fibers made of

Answer 4

Myofibrils

Question 5

Myofibril bundles in muscle are made of

Answer 5

Myofilaments (actin and myosin)

Question 6

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

Answer 6

“Z” lines

Question 7

Actin and myosin are arranged in

Answer 7

Sacromeres

Question 8

Which myofilament is thin, which is thick

Answer 8

Actin is thin, myosin is thick

Question 9

How contraction happens

Answer 9

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

Question 10

The the actin and myosin “unlock” and the muscle

Answer 10

Lengthens and relaxes

Question 11

Proximal end of muscle is the _____

Distal end is the ______

Answer 11

Origin

Insertion

Question 12

What causes flexion and extension in limbs

Answer 12

Contraction and relaxation of muscles

Question 13

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

Answer 13

Acetylcholine (Ach)

Question 14

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

Answer 14

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

Question 15

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

Answer 15

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

Question 16

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

Answer 16

ATP (energy)

Question 17

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

Answer 17

Acetylcholine (Ach)

Question 18

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

Answer 18

Acetylcholinesterase

Question 19

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

Answer 19

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

Question 20

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

Answer 20

Rigor Mortis

Question 21

Why rigor mortis occurs

Answer 21

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

Question 22

Rigor mortis ends how long after death. Why

Answer 22

12-24 hours. The muscles start to break down

Question 23

Muscles breaking down after death is referred to as

Answer 23

Autolysis

Question 24

Exercising first uses _____ produces by aerobic respiration

Answer 24

ATP

Question 25

When oxygen runs out during exercise, what happens

Answer 25

Anaerobic respiration begins making ATP

Question 26

What causes muscles to hurt/ burn during exercise

Answer 26

The lactic acid produces by anaerobic respiration

Question 27

What multiple sclerosis does (MS)

Answer 27

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

Question 28

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

Answer 28

Body attacks nerves, peels off some protective coating | Like fraying an electric cord

Question 29

How muscle paralysis occurs (through poison)

Answer 29

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

Question 30

Examples of poisons used in darts or surgical drugs for paralysis

Answer 30

Curare botulism

Question 31

Why insecticide poising can cause spasms and seizure-like occurrences

Answer 31

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

Question 32

Indications of insecticide poisoning (like organophosphate poisoning)

Answer 32

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

Question 33

How to treat insecticide poisoning

Answer 33

Activated charcoal orally, a bath, injection of atropine

Question 34

What atropine does

Answer 34

Blocks the Ach binding sites on the muscles

Question 35

Hypocalcemia causes what in small breed dogs and cows

Answer 35

Dogs: Eclampsia Cows: milk fever

Question 36

What hypocalcemia is

Answer 36

Deficient in Ca++ and muscles won’t work

Question 37

Signs of hypocalcemia in cows and dogs

Answer 37

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

Question 38

How to treat hypocalcemia | What happens if you do this too much

Answer 38

Treat with IV calcium and increased dietary calcium. | Too much CA++ can cause heart attack

Question 39

Hypertrophy

Answer 39

Increased size of muscles (weights, testosterone)

Question 40

Atrophy

Answer 40

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

Question 41

Dystrophy

Answer 41

Degeneration of muscles

Question 42

Example of a dystrophy disease

Answer 42

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