animal locomotion-skeleton and muscles

Question 1

what are skeletons for

Answer 1

body support, locomotion, protection

Question 2

what are the three broad catigories of skeletons

Answer 2

hydrostatic, exoskeleton, endoskeleton

Question 3

what skeleton type has limited protection

Answer 3

hydrostatic

Question 4

what skeleton type must be shead for growth and what is this process called

Answer 4

its called ecdysis and exoskeletons do this

Question 5

what skeleton type is exposed to bodily fluids and H+ as a byproduct of metabolism

Answer 5

endoskeleton

Question 6

what are the two types of endoskeletons

Answer 6

-calcium carbonate and protein fibers, it easily devolves in acid (starfish)
-calcium phosphate and protein fibers, more resistant to acid, internal stores of Ca+ and PO4- (us)

Question 7

what do vertebrate skeletons rely on

Answer 7

Ca++ homestasis

Question 8

in vertebrate skeletons what is blood Ca++ tightly regulated by

Answer 8

endocrine negative feedback loops

Question 9

what are muscles responsible for

Answer 9

responsible for movement of body

Question 10

where are contractile cells found

Answer 10

in all animals

Question 11

what did true muscle first evolve in

Answer 11

cnidarins

Question 12

what are muscle contractions

Answer 12

shortening based in interactions between:
supporting filament (actin)
a motor protein (myosin)

Question 13

what are the three types of vertebrate muscle

Answer 13

skeletal, cardiac, and smooth

Question 14

what muscle is volentary

Answer 14

skeletal muscle

Question 15

what muscle is striated

Answer 15

skeletal, and cardiac

Question 16

what muscle is unstriated

Answer 16

smooth muscle

Question 17

what is involuntary muscle

Answer 17

cardiac and smooth

Question 18

what is neurogenic muscle

Answer 18

voluntary muscle

Question 19

what is myogenic muscle

Answer 19

involuntary muscle

Question 20

all muscle is…

Answer 20

bioelectric (produces membrane action potential)

Question 21

what is the average and largest usual length of a skeletal muscle cell

Answer 21

ave 3cm, up to 30cm

Question 22

what does shortening of the muscle generate

Answer 22

force and movement

Question 23

what is proximal insertion of muscle

Answer 23

muscle connects closer to the joint-speed

Question 24

what is the distal insertion of a muscle

Answer 24

further away from the joint- strength

Question 25

what are antagonistic pairs

Answer 25

muscles are grouped as such

Question 26

can antagonistic pairs be active at the same time

Answer 26

yes

Question 27

what is sliding filament theory

Answer 27

explains muscle contraction

Question 28

what is the composition of a muscle

Answer 28

muscle---bundle of muscle fibers---muscle fiber---myofibril

Question 29

what is a portion of a myofibril

Answer 29

M line - Z line - A band (H zone in middle) I band

Question 30

on a myofibril what is the dark band and what is the light band

Answer 30

dark A band, light I band

Question 31

how does the neuromuscular junction work

Answer 31

-it has a motor neuron axon terminal (presynaptic) -muscle fiber (postsynaptic) -acetylcholine causes a muscle fibre depolarization -depol results in muscle action potentials

Question 32

what are some features of the neuromuscular junction

Answer 32

-it has acetylcholine gated cation channels (nicotinic receptor) -and indents on the plasma mem of the cell for increased SA

Question 33

how is muscle AP conducted to the interior of the muscle fiber

Answer 33

along the membrane of the t-tubules

Question 34

what is the plasma membrane and the T tubules of the interior of the muscle fiber like

Answer 34

plasma mem- sarcolemma (folded) T tubles- continous with the sarcolemma

Question 35

when you hear the word sarco what can you assume

Answer 35

that its related to muscle

Question 36

what is the sarcoplasmic reticulum

Answer 36

-its like the ER -it stores Ca+ -keeps cytoplasmic Ca+ low, SR Ca+ high

Question 37

how does the sarcoplasmic reticulum keep the Ca+ gradient how it should be

Answer 37

-uses Ca-ATPase to pump Ca++ form cytoplasm to sarcoplasm

Question 38

what us a ryanodine receptor (RyR)

Answer 38

Ca++ channel in sarcolemma

Question 39

what is a dihydropyridine receptor (DHPR)

Answer 39

voltage gated channels in t-tubule membrane-at rest plugs RyR

Question 40

what does the muscle action potential (MAP) do to dihydropyridine receptor (DHPR)

Answer 40

-it produces a conformational change in DHPR -which unblocks RyR -Ca+ defuses out of sarcoplasmic reticulum into sarcoplasm along large concentration gradient

Question 41

what are muscle cell contractions stimulated by

Answer 41

motor neurons form somatic nervous system

Question 42

one myofibril is many...

Answer 42

sarcomeres

Question 43

what part of the myofilaments is myosin

Answer 43

A band

Question 44

what part of the myofilaments is actin

Answer 44

I band

Question 45

what is the H zone on a myofibril

Answer 45

myosin only, bisected by M line

Question 46

what is the Z disk on a myofibril

Answer 46

it anchors actin

Question 47

what is the M line on a myofibril

Answer 47

it anchors myosin

Question 48

what regulates interactions with actin and myosin

Answer 48

troponin and tropomyosin

Question 49

what happens when actin and myosin come into contact

Answer 49

interactions make contractions, actin slides on myosin

Question 50

what gets pulled closer as actin and myosin come into contact

Answer 50

Z line gets pulled closer

Question 51

what causes actin and myosin to move filaments past eachother

Answer 51

change in myosin shape after cross bridge formation

Question 52

where does Ca2+ bind to on actin filaments

Answer 52

it binds to troponin

Question 53

what happens in presents of high sarcoplasmic Ca+

Answer 53

the cycle of binding and unbinding continues

Question 54

what is ATP required for when it comes to cross bridge binding

Answer 54

-required to detach actin/myosin -also needed for Ca+ pump on sarcolemma

Question 55

what happens if no ATP is produced to detach actin and myosin

Answer 55

then filaments remain bound (rigor mortis)

Question 56

what is the muscle contraction due to

Answer 56

-continual crossbridgle cycling -the formation of many crossbridges per sarcomere

Question 57

what is the length of a sarcomere

Answer 57

2.5 micro m

Question 58

what is the distance each sarcomere can shorten

Answer 58

0.25 micro m

Question 59

what is neural regulation of skeletal muscles

Answer 59

reflex arcs

Question 60

what is reflex arcs

Answer 60

stretch receptors and motor neurons connected to the CNS

Question 61

how do reflex arcs operate

Answer 61

-automatically -integrated with conscious motor control by CNS

Question 62

what are reflex arcs important for

Answer 62

in posture, coordinating limb movements

Question 63

what does neural stimulation always do to skeletal muscles

Answer 63

it always shortens it

Question 64

what is one motor unit

Answer 64

motor unit=one neuron plus all muscle fibers it contacts

Question 65

what controls muscle activity

Answer 65

threshold

Question 66

what will a a restimulated action potentials with rest in between result in

Answer 66

single twitches

Question 67

what will a action potental that has been restimulated before it has completely relax result in

Answer 67

summed twitches

Question 68

what is tetanus

Answer 68

-if muscle is stimulated so rapidly that it doesnt have opportunity to relax at all between stimuli -at the end it goes down because stimulations ceases or fatuigue begins

Question 69

what is an example of stretch activated muscles

Answer 69

asynchronous flight muscle

Question 70

what are asynchronous flight muscles

Answer 70

-smaller SR-more sarcomeres -indirectly attached to wing Mn AP:cantractions <1 (one AP leads to many contractions of muscle) -mechanical coupling, more efficent use of ATP