quiz 3: Muscles

Question 1

excitable

Answer 1

• polarized at rest and can lose it
• fires action potentials just like neurons

Question 2

contractile

Answer 2

• muscles will use action potential for contraction
• force & tension (pull or push)

Question 3

what are the three types of muscle tissues

Answer 3

• cardiac
• smooth
• skeletal

Question 4

skeletal muscles

Answer 4

• associates with bones
• push and pulls on bones to create movement of the body
• is a sinsission
• has striations that mark boundaries between sarcomeres
• has many nuclei

Question 5

sinsission

Answer 5

1 large cell that never goes through cytokenisis. it will continue to grow making a long skeletal muscle.

Question 6

cardiac muscle

Answer 6

• makes up myocardium (allows for heart to contract and beat)
• has striations and sarcomeres
• intercalated disks
• gap junctions
• nucleus located before branching point
• somatic motor neuron has to talk to each cell

Question 7

smooth muscle

Answer 7

• goes around hollow organs & walls of blood vessels
• the myosin and actin inside are flimsy
• goes from big to small towards the center or away from it
• myosin grabs onto anything it can find

Question 8

what two muscle tissues are the most similar? what makes them different?

Answer 8

cardiac and skeletal muscles are very similar. what makes them different is how thy are initiated

Question 9

sarcomeres

Answer 9

the part of the muscle tissue that is actually contracting

Question 10

intercalated disks

Answer 10

where the cardiac muscle branches and is full of gap junctions

Question 11

gap junctions

Answer 11

cell membrane is attached to each other and has channels to allow for transportation of large things like ribosomes.

Question 12

which muscle is controlled by the motor division of PNS?

Answer 12

skeletal

Question 13

which muscle only responds to signals from somatic motor neurons?

Answer 13

skeletal

Question 14

origin meaning

Answer 14

closest to the trunk

Question 14

which muscle is attached to bones and tendons

Answer 14

skeletal

Question 15

insertion meaning

Answer 15

more distal or more mobile attachment

Question 16

flexor

Answer 16

brings bones closer

Question 17

exstensor

Answer 17

moves bone away

Question 18

antagonistic muscle groups

Answer 18

muscles that work opposite of each other

Question 19

muscle cell is the same as what?

Answer 19

muscle fiber

Question 20

cell membrane is the same as what?

Answer 20

sarcolemma

Question 21

cytoplasm is the same as what?

Answer 21

sarcoplasm

Question 22

modified endoplasmic reticulum is the same as what?

Answer 22

sarcoplasmic reticulum

Question 23

muscle segments

Answer 23

structures made of muscle cells
- all cells inside have the same specific action and largely work together since they have the same set of neurons

Question 24

what surrounds and protects muscle cells?

Answer 24

connective tissues

Question 25

where do action potentials travels

Answer 25

along the membrane

Question 26

t-tubule

Answer 26

allows processes to happen faster since they travel straight down to its destination

Question 27

myofibril

Answer 27

long tube made of sarcomeres attached to eachother

Question 28

what is a sarcomere made up of?

Answer 28

two types of microfilaments - myosin and actin

Question 29

myosin

Answer 29

- thick - cannot move - has two "hands" that pull to shorten muscles

Question 30

Actin

Answer 30

- thin - anchored to z-disc

Question 31

A- band

Answer 31

cannot change shape (myosin)

Question 32

muscle tension

Answer 32

force created by muscle

Question 33

load

Answer 33

- the actual weight - weight or force opposing contraction

Question 34

contraction

Answer 34

- shortening - creation of tension in muscle

Question 35

relaxation

Answer 35

- lengthening - release of tension

Question 36

muscle twitch

Answer 36

- moment of initiating contracting to when it is completely reset - a single contraction- relaxation style

Question 37

two major phases of skeletal muscle contraction

Answer 37

- neuromuscular junction events - cross-bridge cycle

Question 38

neuromuscular junction events

Question 39

crossbridge

Answer 39

the physical connection between myosin and actin

Question 40

cycle

Answer 40

happens over and over again as long as tropomyosin is out of the way

Question 41

myosin heads

Answer 41

- are arranged in pairs (arms) movine 180 degrees out of sync which makes the load move smoothly

Question 42

the steps for myosin to pull on actin

Answer 42

- as soon as tropomyosin moves, myosin can attach right away to actin and form a transient state (no tension but they are attached) - ATP will bind with myosin and release it from the actin - to hydrolyze ATP, ATPase comes and turns it into ADP & Pi - energy from reaction is used to change the shape of myosin and is stored in the myosin head - myosin begins to pull on actin performing the power stroke, causing contraction - ADP & Pi pop off and myosin returns to its original cocked state

Question 43

what are the two types of contractions?

Answer 43

- isometric - isotonic

Question 44

isometric contractions

Answer 44

create force without moving a load iso=same metric=length

Question 45

isotonic contractions

Answer 45

- create force and move load - where there is change in shape - concentric action - eccentric action

Question 46

concentric action

Answer 46

shortening action

Question 47

eccentric action

Answer 47

- lengthening action - the load is moving the muscle more than the muscle is moving the load - resist movement so the load doesn't go down too fast

Question 48

elastic series elements

Answer 48

things that are stretchy and are in line

Question 49

tetanic contraction

Answer 49

- muscle twitch length is longer than refractory period for the actual muscle - this means that the muscle potentially can receive more than one action potential in the time it takes a twitch to complete

Question 50

tetanus

Answer 50

- temporal summation sustained contraction - contraction is maintained by repeated stimulation

Question 51

fused

Answer 51

when there is no variation in force

Question 52

unfused

Answer 52

you can see individual responses - the little bit of relaxation in between helps muscle fatigue slower

Question 53

maximal tetanic contraction

Answer 53

the contraction will not get any further than this point and will fatigue faster

Question 54

summation

Answer 54

muscle will contract harder for longer.