ANPH - exam 1 (Answered) 60
Questions and Correct Answers. 100%
Correct, 2024/2025.
(3) All muscle fibers are?
excitable, extensible, elastic
Skeletal muscles - 3 layers
epimysium - connects to tissues
perimysium
endomysium
Purpose of skeletal muscles (3)
maintain posture
stabilizes joints
generates heat
Sarcolemma
cell membrane
Saroplasm
cytoplasm
Sarcoplasmic reticulum
specialized smooth ER
Sarcomere
functional unit of muscle fiber
Tropomyosin and Troponin
regulatory protein
Myofibril
long filament in the sarcoplasm (contain thin actin and myosin filaments)
Skeletal muscle sliding filament theory
1. myosin head splits ATP
2. Myosin head attaches to actin = crossbridges
3. Myosin head pulls to sarcomere center
4. Crossbridges detach
Muscle strength is determined by what?
how many fibers are stimulated + number of motor nerve fibers activated by the motor cortex
, Concentric isotonic
force > resistance
muscle shortens
Eccentric isotonic
resistance > force
muscle lengthens
Hypotonia
lack of tone
brain does not send enough impulses to the muscles
Hypertonia
increased muscle tone
too much signals from the brain to the muscles
Slow twitch fibers
need constant supply of oxidative blood
- burns thru slowly
Fast twitch
- generates ADP
- burns thru quickly
Fast glycolytic
tires quickly because it burns thru blood supply quickly
Steps of Sliding filament theory
1. Myosin splits ATP -> ADP + P
2. Myosin binds to actin
3. Myosin heads rotate towards center
4. Cross bridges detach from action + form ATP (power)
A band
length of the fiber
when overlapped = creates parts of thin fibers
I band
area where thin fibers that don't overlap
- decreases during contraction
H band
area where thick fibers don't overlap
- decreases during contraction
M band
Questions and Correct Answers. 100%
Correct, 2024/2025.
(3) All muscle fibers are?
excitable, extensible, elastic
Skeletal muscles - 3 layers
epimysium - connects to tissues
perimysium
endomysium
Purpose of skeletal muscles (3)
maintain posture
stabilizes joints
generates heat
Sarcolemma
cell membrane
Saroplasm
cytoplasm
Sarcoplasmic reticulum
specialized smooth ER
Sarcomere
functional unit of muscle fiber
Tropomyosin and Troponin
regulatory protein
Myofibril
long filament in the sarcoplasm (contain thin actin and myosin filaments)
Skeletal muscle sliding filament theory
1. myosin head splits ATP
2. Myosin head attaches to actin = crossbridges
3. Myosin head pulls to sarcomere center
4. Crossbridges detach
Muscle strength is determined by what?
how many fibers are stimulated + number of motor nerve fibers activated by the motor cortex
, Concentric isotonic
force > resistance
muscle shortens
Eccentric isotonic
resistance > force
muscle lengthens
Hypotonia
lack of tone
brain does not send enough impulses to the muscles
Hypertonia
increased muscle tone
too much signals from the brain to the muscles
Slow twitch fibers
need constant supply of oxidative blood
- burns thru slowly
Fast twitch
- generates ADP
- burns thru quickly
Fast glycolytic
tires quickly because it burns thru blood supply quickly
Steps of Sliding filament theory
1. Myosin splits ATP -> ADP + P
2. Myosin binds to actin
3. Myosin heads rotate towards center
4. Cross bridges detach from action + form ATP (power)
A band
length of the fiber
when overlapped = creates parts of thin fibers
I band
area where thin fibers that don't overlap
- decreases during contraction
H band
area where thick fibers don't overlap
- decreases during contraction
M band
