muscular Flashcards
1
Q
responsible for movement of the arms, legs, heart, and other parts of the body; maintenance of posture; respiration; production of body heat; communication; constriction of organs and vessels; and heartbeat.
A
mucles
2
Q
responsible for most body movements
A
skeletal muscle
3
Q
found in the walls of hollow organs and tubes and moves substances through them
A
smooth muscle
4
Q
in the heart and pumps blood.
A
cardiac muscle
5
Q
shortens forcefully
A
contractility
6
Q
responds to stimuli
A
excitability
7
Q
can be stretched and still contract
A
extensibility
8
Q
recoils to resting length
A
elasticity
9
Q
shortens forcefully but lengthens passively
A
muscle tissue
10
Q
associated with connective tissue, blood vessels, and nerves.
A
skeletal muscle fibers
11
Q
bundles of muscle fibers, are covered by the connective tissue layer called the perimysium.
A
muscle fascicles
12
Q
The entire muscle is surrounded by a connective tissue layer
A
epimysium
13
Q
extend together with arteries and veins through the connective tissue of skeletal muscles.
A
motor neurons
14
Q
axons of motor neurons branch, and each branch projects to a muscle fiber to form a neuromuscular junction.
A
perimysium
15
Q
axons of motor neurons branch, and each branch projects to a muscle fiber to form a neuromuscular junction.
A
perimysium
16
Q
single cell consisting of a plasma membrane (sarcolemma), cytoplasm (sarcoplasm), several nuclei, and myofibrils.
A
muscle fiber
17
Q
what components of a muscle fiber include the sarcolemma, the T tubules, and the sarcoplasmic reticulum.
A
electrical components
18
Q
what components of a muscle fiber include the myofibrils and the myofilaments.
A
mechanical component
19
Q
composed of two major protein fibers: actin and myosin.
A
myofibrils
20
Q
consist of actin (composed of G actin monomers), tropomyosin, and troponin.
A
actin myofilaments
21
Q
consisting of heads and a rodlike portion, constitute myosin myofilaments.
A
myosin molecules
22
Q
forms when the myosin binds to the actin.
A
cross bridge
23
Q
organized to form sarcomeres.
A
actin and myosin
24
Q
bound by Z disks that hold actin myofilaments.
A
sarcomeres
25
the location where a motor neuron is in close proximity to the muscle fiber.
neuromuscular junction
26
contains synaptic vesicles that house the neurotransmitter, acetylcholine.
motor neuron axon terminal
27
-are polarized, which means that a charge difference, called the resting membrane potential
-becomes polarized because the tendency for K+ to diffuse out of the cell is resisted by the negative charges of ions and molecules inside the cell.
plasma membrane
28
-responsible for membrane permeability and the resting membrane potential.
-responsible for producing action potentials.
ion channels
29
The charge difference across the plasma membrane of cells
resting membrane potential
30
-results from an increase in the permeability of the plasma membrane to Na+.
-the action potential results when many Na+ channels open in an all-or-none fashion.
depolarization
31
the action potential occurs when the Nat channels close and the K+ channels open briefly.
repolarization
32
separates the presynaptic terminal of the axon from the motor end-plate of the muscle fiber.
synaptic cleft
33
released from the presynaptic terminal binds to receptors of the motor end-plate, thereby changing membrane permeability and producing an action potential.
acetylcholine
34
splits acetylcholine into acetic acid and choline.
acetylcholinesterase
35
reabsorbed into the presynaptic terminal to re-form acetylcholine.
choline
36
a T tubule and two terminal cisternae (an enlarged area of sarcoplasmic reticulum).
triad
37
move into the T tubule system, causing Ca* channels to open and release Ca2+ from the sarcoplasmic reticulum.
action potentials
38
diffuse from the sarcoplasmic reticulum to the myofilaments and bind to troponin, causing tropomyosin to move and expose active sites on actin to myosin.
calcium ions
39
occurs when myosin heads bind to active sites on actin, myosin changes shape, and actin is pulled past the myosin.
contraction
40
occurs when calcium is taken up by the sarcoplasmic reticulum, ATP binds to myosin, and tropomyosin moves back so that active sites on actin are no longer exposed to myosin.
relaxation
41
-required for the cycle of cross-bridge formation, movement, and release.
-required to transport Ca+ into the sarcoplasmic reticulum and to maintain normal concentration gradients across the plasma membrane.
ATP
42
-transported into the sarcoplasmic reticulum.
-diffuse away from troponin, preventing further cross bridge formation
calcium ions
43
-the contraction of a single muscle fiber or a whole muscle in response to a stimulus.
-has lag, contraction, and relaxation phases.
muscle twitch
44
results in graded contractions of increased force through either summation or recruitment.
stimulus of increasing magnitude
45
partial relaxation between contractions; complete tetanus is no relaxation between contractions.
incomplete tetanus
46
increases the force of contraction (wave summation).
stimulus of increasing frequency
47
cause muscles to shorten and tension to increase.
concentric contraction
48
cause muscle to lengthen and tension to decrease gradually.
eccentric contractions
49
the maintenance of steady tension for long periods.
muscle tone
50
break down ATP slowly and have a well-developed blood supply, many mitochondria, and myoglobin.
slow twitch muscle fibers
51
break down ATP rapidly.
fast twitch muscle fibers
52
have a well-developed blood supply, more mitochondria, and more myoglobin.
type IIa muscle fibers
53
have large amounts of glycogen, a poor blood supply, fewer mitochondria, and little myoglobin.
type IIb muscle fibers
54
hypertrophy
muscle increase
55
atrophy
muscle decrease
56
develops type Ilb muscle fibers.
anaerobic exercise
57
develops type I muscle fibers and changes type IIb muscle fibers into type Ila fast-twitch muscle fibers.
aerobic exercise
58
-The ATP synthesized by anaerobic respiration provides energy for a short time during intense exercise.
-produces ATP less efficiently but more rapidly than aerobic respiration. Lactate levels increase because of anaerobic respiration.
anaerobic respiration
59
-The ATP synthesized by aerobic respiration produces energy for muscle contractions under resting conditions or during exercises such as long-distance running. Although ATP is produced more efficiently, it is produced more slowly.
-produces more ATTP than anaerobic respiration, but at a slower rate.
aerobic respiration
60
the decreased ability to do work, can be caused by the central nervous system, depletion of ATP in muscles, or depletion of acetylcholine in the neuromuscular junction.
fatigue
61
the inability of muscles to contract or relax
physiological contracture
62
stiff muscles after death result from inadequate amounts of ATP.
rigor mortis
63
caused by inflammation in the muscle.
soreness
64
spindle-shaped with a single nucleus. They have actin myofilaments and myosin myofilaments but are not striated.
smooth muscle cells
65
poorly developed, and caveolae may function as a T tubule system.
sarcoplasmic reticulum
66
are striated, have a single nucleus, are connected by intercalated disks (and thus function as a single unit), and are capable of autorhythmicity.
cardiac muscle fibers
67
causes a certain movement
agonist
68
acts in opposition to the agonist.
antagonist
69
muscles that function together to produce movement.
synergists
70
mainly responsible for a movement.
prime movers
71
stabilize the action of prime movers.
fixators
72
The origins of facial muscles
skull bones or fascia
73
into the skin, causing movement of the facial skin, lips, and eyelids.
insertions
74
Three pairs of muscles close the jaw; gravity opens the jaw. Forced opening is caused by the lateral pterygoids and the hyoid muscles.
mastication
75
muscles change the shape of the tongue; extrinsic tongue muscles move the tongue.
intrinsic tongue
76
can depress the jaw and assist in swallowing.
hyoid muscles
77
open and close the openings to the nasal cavity, auditory tubes, and larynx.
muscles
78
the origins of these muscles are mainly on the cervical vertebrac (except for the sternocleidomastoid); the insertions are on the occipital bone
neck muscles
79
-These muscles extend, laterally flex, rotate, or flex the vertebral column.
-A more superficial group of muscles runs from the pelvis to the skull, extending from the vertebrae to the ribs.
-A deep group of muscles connects adjacent vertebrae.
vertebral column muscles
80
-Most respiratory movement is caused by the diaphragm.
-Muscles attached to the ribs aid in respiration.
thoracic muscles
81
hold and protect abdominal organs and cause flexion, rotation, and lateral flexion of the vertebral column.
abdominal wall muscles
82
These muscles support the abdominal organs inferiorly.
pelvic diaphragm and perineum muscles
83
how many are the muscles attach the scapula to the trunk and enable the scapula to function as an anchor point for the muscles and bones of the arm
six
84
how many muscles attach the humerus to the scapula.
seven
85
how many muscles attach the humerus to the trunk.
two additional muscles
86
These muscles cause flexion and extension of the shoulder and abduction, adduction, rotation, and circumduction of the arm.
arm movements
87
the elbow are accomplished by three muscles in the arm and two in the forearm.
flexion and extension
88
accomplished primarily by forearm muscles.
supination and pronation
89
muscles in the forearm.
extrinsic hand muscles
90
muscles are in the hand
instrinsic hand muscles
91
cause flexion of the hip.
anterior pelvic muscles
92
responsible for extension of the hip and abduction and rotation of the thigh.
muscles of the buttocks
93
extend the leg,
anterior thigh muscles
94
flex the leg.
posterior thigh muscles
95
muscles flex the hip and extend the knee.
anterior compartment
96
muscles adduct the thigh.
medial compartment
97
muscles extend the hip and flex the knee.
posterior compartment
98
cause dorsiflexion, inversion, or eversion of the foot and extension of the toes.
anterior compartment
99
plantar flex and evert the foot
lateral compartment
100
flex the leg, plantar flex and invert the foot, and flex the toes.
posterior compartment
101
flex or extend, and abduct or adduct, the toes.
intrinsic foot muscle
