muscular system

Question 1

what are the three vertebrae muscles tissues?

Answer 1

smooth, skeletal, cardiac

Question 2

characteristics of cardiac muscle

Answer 2

found in the heart, involuntary, makes up tissues of circulatory pumps, uninucleate, striated (stripped apperance), held together by intercalated discs, does change internal volume as it contracts

Question 3

characteristics of smooth muscle

Answer 3

found in veins/arteries, found in walls of stomach, uterus, involuntary, uninucleate, spindle shaped cells, does change internal volume as it contracts

Question 4

characteristics of skeletal muscle

Answer 4

found attached to bone, or in eyes, responsible for movement, voluntary, striated (stripped appearance), multinucleate, cylindrical cells

Question 5

all muscle tissues can

Answer 5

extend, contract, and react (be stimulated)

Question 6

flexors

Answer 6

muscles that decrease angle in a joint

Question 7

extenders

Answer 7

muscles that extend/widen the angle in a joint

Question 8

flexors of knee

Answer 8

biceps femoris, semitendinosus, semimembranosus… make up the hamstring

Question 9

extenders of the knee

Answer 9

vastus lateralis, rectus femoris, vastus, medialis, vastus intermedius, these make up the quadriceps

Question 10

tendons

Answer 10

connect bone to muscle (think achilles tendon)

Question 11

ligaments

Answer 11

connect muscle to muscle (think ACL…)

Question 12

origin

Answer 12

closer to the body, attachment site that usually does not move when muscles contract

Question 13

insertion

Answer 13

farther from the body, attachment site that moves when the muscles contract, insertion is PULLED towards origin

Question 14

what happens when we flex/extend our arm muscles?

Answer 14

biceps contract/shorten and triceps relax/lengthen when we flex… triceps contract/shorten and biceps relax/lengthen when we extend

biceps flex muscles
triceps extend muscles

Question 15

what happens when we flex/extend our leg muscles?

Answer 15

hamstrings contracted quads relaxed when you flex, quads are contracted and hamstrings relaxed when you extend

quads extend muscles
hamstrings flex muscles

Question 16

antagonist muscles

Answer 16

muscles that do opposite actions ex: quads + hamstrings

Question 17

name largest to smallest bundle in muscles

Answer 17

muscles - fascicles - muscle fibers/cells - myofibril - myofilaments

Question 18

actin is

Answer 18

thin filaments

Question 19

myosin is

Answer 19

thick filaments

Question 20

what causes the striped striated apperance of muscle cells?

Answer 20

bundles of myofibrils contain sarcomeres, that repeat, and cause this look.

Question 21

what is the slinding filament theory?

Answer 21

this explains the contracting of muscles, and changes of muscle length within a sacromere. atp is used to “shorten” the muscle

Question 22

what are the 3 steps that occur to “shorten” the sarcomere?

Answer 22

1) CROSS BRIDGE FORMS -myosin head binds to actin through atp hydrolyzing
2) POWER STROKE - release of ADP + P allows thin filament to slide to center
3) CROSS BRIDGE BREAKS - new atp bonds and helps think filaments detach

Question 23

sarcomeres consist of

Answer 23

thick filaments - myosin, thin filaments - actin, m line - holding thick filaments together, z line - ends of sarcomere where thin filaments attach + cause striped look

Question 24

do filaments shorten?

Answer 24

no they do not shorten, they slide