Flashcards in Chapter 8 Deck (44):
0
How many muscles do we have
600
1
Fibrous connective tissue covering muscles
Fascia
2
Add muscles to bone
Tendons
3
Sheet of connective tissue which attaches muscles to muscle
Aponeurosis
4
Single muscle cell
Muscle fiber
5
Fibers made out of proteins myosin (thick) and actin (thin) that plays a role
Myofibrils
6
What produces striations?
Myofibrils
7
Connection between motor neuron and muscle fiber
Neuromuscular junction
8
Motor neuron and muscle fibers it controls
Motor unit
9
Neurotransmitter that stimulates a skeletal muscle fiber
Acetylcholine
10
Steps for stimulus for contraction
Muscle impulses signals the release of calcium ions
Linkages form between actin and myosin and muscle fibers contract
Acetylcholine is decomposed by enzyme acetylcholinesterase
Calcium ion transported back
Linkages between actin and myosin break and muscle fiber relaxes
11
What is the energy source for contraction
ATP
12
Red pigment in blood that carries oxygen
Hemoglobin
13
Reddish brown pigment, only found in muscles that carries oxygen
Myoglobin
14
What is the advantage of having hemoglobin and myoglobin in the same place
This reduces muscle requirement for continuous blood supply
15
How does lactic acid form
During strenuous exercise, oxygen deficiency may cause lactic acid to accumulate in muscles
16
Amount of oxygen liver requires to convert lactic acid to glucose and to restore ATP and creatine phosphate
Oxygen debt
17
3 causes of muscle fatigue
Caused by lactic acid, poor blood supply, or lack of acetylcholine in motor neurons
18
Minimal strength required to cause contractions
Threshold stimulus
19
Recording of an electrically stimulated muscle
Myogram
20
Single contraction that lasts only a fraction of a second
Twitch
21
Delay between time stimulus was applied and time muscle responded
Latent period
22
Increased force of contraction by a muscle when twitches occur so rapidly that next twitch occurs before previous one relaxes
Summation
23
Forceful, sustained contraction without even partial relaxation
Tetanic contraction ????
24
Explain process of recruitment of motor units
Increase in # of motor units being activated as more motor neurons respond to higher stimuli
As stimulus increases, requirement of motor units continue until all possible units are activated and muscle contracts with maximum tension
25
Summation and recruitment together can produce sustained contraction of increasing strength
Sustained contractions
26
When a muscle is a rest, some sustained contraction occur
Muscle tone
27
Name 2 types of smooth muscle and differ them
Multiunit smooth muscle- fibers separated and less organized found in iris of eye and walls of blood vessels, contract only in respond to stimulation from motor nerves
Lisceral- sheets of cells in close contact, follow in walls of hollow organs, can stimulate each other and cause repeated contractions=rhythmically
28
Wavelike motion occurring in intestines to force contents along
Peristalsis
29
Immovable end of the muscle
Origin
30
Moveable end of the muscle
Insertion
31
Provides most of the movement
Prime mover (agonist)
32
Assist the prime mover
Synergists
33
Resists action of prime mover
Antagonists
34
Criteria they use in naming muscles (6) q
Size, shape, location, action, # of attachments, and direction of fibers
35
Factors that limit endurance
Loss of muscle glycogen
Loss of fat reserves
Low level of blood sugar
Lack of oxygen
Accumulation of lactic acid (lack of oxy)
Heat build up in muscles
36
3 types of muscle fuel
Carbohydrates-primary fuel
Fat-secondary fuel
Protein- never be a source of fuel
37
Hitting the wall
When muscles run out of glycogen and become uncoordinated and hurt
38
Depletion
Your muscles will learn to store more fuel if their supply is used up frequently
39
Carbohydrate packing
Limit carb in take for three days, then next 3 days eat many carbs
40
Bonking
Body runs out of liver glycogen, blood sugar drops, brain can't function properly
41
Similarities and differences between smooth and skeletal q
Smooth lacks striations; skeletal has them
BOTH contain actin and myosin; BOTH make contractions happen
Smooth-2 neurotransmitters(acetylcholine and norepinephrine); skeletal only one (acetylcholine)
Smooth-contracts slower but maintains contraction longer than skeletal
42
Similarities of cardiac and smooth
Similarities of cardiac and skeletal
1. Involuntary and have myosin and actin
2. Composed of striated cells
43