Font size
WorksheetsMuscular System Contract
Total questions: 85
Worksheet time: 1hrs 25mins
Myofilaments bundled together make:
Myofibrils
Fascicles
Fibers
The whole muscle
Myofibrils bundled together make:
One Cell; Fascicles
One Cell; Muscle Fibers
The whole Muscle
Fibers bundled together make:
Myofibrils
One cell
Fascicle
The whole muscle
Fascicles bundled together make:
Myofribrils
One cell; Muscle fibers
The whole muscle
The connective tissue covering 1 skeletal muscle cell fiber is called __________.
Epimysium
Perimysium
Aponeurosis
Endomysium
The connective tissue covering a bundle of skeletal muscle fibers (Fascicles) is called __________.
Perimysium
Endomysium
Epimysium
Aponeurosis
The connective tissue covering the whole muscle is called __________.
Aponeurosis
Endomysium
Perimysium
Epimysium
Tendons are made of what type of connective tissue?
Dense irregular connective tissue
Reticular connective tissue
Areolar connective tissue
Dense regular connective tissue
A sheet of tendons is called a(n):
Endomysium
Aponeurosis
Perimysium
Epimysium
What term is used for this feature: muscles that can receive signals from the nervous system and respond to a stimulus.
Excitability
Contractibility
Extensibility
Elasticity
What term is used for this feature: muscles can shorten forcibly when stimulated, they contract.
Excitability
Contractibility
Extensibility
Elasticity
What term is used for this feature: muscles can stretch beyond their resting length.
Excitability
Contractibility
Extensibility
Elasticity
What term is used for this feature: muscles can return back to their resting length (it can bounce back.)
Excitability
Contractibility
Extensibility
Elasticity
What is another name for the plasma membrane of a muscle cell?
Sarcolema
Sarcoplasm
Myoglobin
Aponeurosis
What is another name for the cytoplasm of a muscle cell?
Sarcolema
Sarcoplasm
Myoglobin
Aponeurosis
What is the function of myoglobin?
Carries CO2 from the muscles to the lungs
Makes ATPase
Gives energy to the muscle cell
Stores extra O2 inside a muscle cell
Why do muscles need a lot of mitochondria?
They need to make a lot of ATP to contract the muscle
They need to make a lot of ATP to signal to the brain
They need to store O2 inside the cells
They need energy for the sarcoplasm to contract
Which type of muscle gets tired?
Cardiac
Smooth
Skeletal
What is stored inside the sarcoplasmic reticulum?
K+
Na+
Ca2+
Cl-
What is the name of the sarcoplasmic reticulum in other cells?
Rough endoplasmic reticulum
Smooth endoplasmic reticulum
Golgi body apparatus
What is the function of T-tubules?
Conduct electrical signals from the sarcolema
Conduct electrical signals from the sarcoplasm
Conduct electrical signals from the dendrites
Conduct electrical signals from the Ca2+ channels
Which of the following is included in a triad?
Sarcoplasmic Reticulum 1
Tropomyosin
Troponin C
Sarcoplasmic Reticulum 2
T-tubules
What does the thick myofilament include?
Actin, Troponin, and Tropomyosin
Troponin and Tropomyosin
Only Tropomyosin
Only Myosin
What does the thin myofilament include?
Only Actin
Only Tropomyosin
Actin, Troponin, and Tropomyosin
Myosin and Actin
Myofilaments are organized into structures called:
Myofibrils of Fasicles
Myofibrils of Sarcolemas
Myofibrils of Tropomyosin
Myofibrils of Sarcomeres
What is another name for A-bands?
Light band
Thick band
Dark band
Thin band
What is another name for I-bands?
Light band
Thick band
Thin band
Dark band
What myofilament is in the I-band?
Thick myofilament
Thin myofilament
What myofilament is in the A-band?
Thick myofilament
Thin myofilament
What is the function of titin?
stores extra O2 inside of muscle cells
binds Ca2+ to the actin sites
blocks the binding site for myosin on actin when the muscle is at rest
anchors the thick and thin myofilaments to the Z-line
Which myofilament has a flipping head?
Thin myofilament (actin)
Thick myofilament (myosin)
Which of the following are proteins within a thin myofilament?
Actin x 2 strands
Tropomyosin x 2 strands
Troponin C, T, and I
Myosin x 2 strands
What enzyme would break down ATP and is found in the myosin head?
ATPase
ATP Catalase
ATP anabolase
Protease
What is the function of Tropomyosin?
Store O2 within the muscle cell
Breaks down ATP to release energy
Binds Ca2+ "yanking" the troponin out of the binding site to start contraction
Blocks the binding site for myosin on the actin myofilament when the muscle is at rest
What is the function of Troponin C?
Store O2 within the muscle cell
Breaks down ATP to release energy
Binds Ca2+ "yanking" the troponin out of the binding site to start contraction
Blocks the binding site for myosin on the actin myofilament when the muscle is at rest
What is the function of Troponin T?
Store O2 within the muscle cell
Breaks down ATP to release energy
Binds Ca2+ "yanking" the troponin out of the binding site to start contraction
It is a structural protein that holds everything together
Blocks the binding site for myosin on the actin myofilament when the muscle is at rest
What is the function of Troponin I?
Breaks down ATP to release energy
Binds Ca2+ "yanking" the troponin out of the binding site to start contraction
It is a structural protein that holds everything together
It "turns off" the contraction at the end of the cycle
What two chemicals are needed to contract a muscle?
K+
Cl-
Ca2+
Na+
ATP
Where is calcium stored when the muscle is not contracting?
Stored inside the sarcoplasmic reticulum
Stored inside the endoplasmic reticulum
Stored inside the triad
Stored inside Tropomyosin
How is calcium involved with contraction?
Pulls Troponin C which returns tropomyosin to the actin binding site
Pulls Troponin C which yanks tropomyosin away from the actin binding site
Signals the myosin head to flip
It is the location the myosin head binds to when given ATP
What are the two functions of ATP in muscle contraction?
Releases Ca2+
Pulls tropomyosin away from the actin binding site
Energize myosin head to form a cross-bridge and flip
Carry electrical signals to every sarcoplasmic reticulum
Detach the myosin head from actin and resets it for the next contraction
What is a triad made of?
2 terminal cisterns of sarcoplasmic reticulum
1 T-tubule
1 terminal cistern of sarcoplasmic reticulum
2 T-tubules
What is the function of a T-tubule?
Pulls tropomyosin from the actin binding sites
Detach the myosin head from actin and reset it for the next contraction
Carry electrical signals to every sarcoplasmic reticulum at once
Energize myosin head to stick and flip
When the muscle is at rest ____ is blocking the site on the ____ myofilament.
tropomyosin, myosin
troponin I, actin
tropomyosin, actin
troponin I, myosin
When the muscle is stimulated by action potential, ____ is released from the sarcoplasmic reticulum and binds to ________.
K+, troponin C
Ca2+, tropomyosin
Ca2+, troponin C
K+, tropomyosin
When Ca2+ binds to Troponin C, it pulls on the ______, moving it out of the way so the myosin head can stick to the _____ binding site.
sarcoplasmic reticulum, t-tubule
tropomyosin, actin
thin myofilament, myosin
troponin I, actin
To contract muscles we need:
An action potential in the muscle cell
Calcium release from the sarcoplasmic reticulum
Place calcium back into the sarcoplasmic reticulum
Return to resting membrane potential
Release of ACh from the neuron
To relax muscles we need to:
Get rid of ACh
Release ACh from the neuron
Return to resting membrane potential -70mV
Calcium release from the sarcoplasmic reticulum
Place calcium back into the sarcoplasmic reticulum
How does the muscle get rid of ACh?
Use sodium potassium ATPase pump
Use the power of ATP
Use the enzyme Acetylcholine esterase
Release Calcium from the sarcoplasmic reticulum
How do the muscle cells return to resting membrane potential? (-70mV)
Use sodium potassium ATPase pumps
Use the enzyme Acetylcholine esterase
Use ATP to power calcium pumps
Release of ACh from the neuron
How do muscle cells place calcium back into the sarcoplasmic reticulum?
Use enzyme Acetylcholine esterase
Use sodium potassium ATPase pumps
Release ACh from the neuron
Use ATP to power the calcium pumps that put it back
What is muscle tone?
The way your muscles look after a work out because contracting it keeps the muscle healthy and strong
It is the action potential of your muscles look while exercising
At rest your muscle is periodically being zapped to keep is strong and healthy
The complete tetanus of a muscle after a work out
What is a motor unit?
1 motor neuron and the muscle cells it supplies
10-15 motor neurons and the muscle cells they supply
500 motor neurons and the muscle cells they supply
the triad is considered the motor unit
A small motor unit is considered 1 neuron with _____ fibers.
100-500
20-70
10-15
1-10
A large motor unit is considered 1 neuron with _____ fibers.
100-500
500
1000
5000
A small motor unit is found in the ____.
Hands and Eyes
Gluteus Maximus and Rectus Femoris
Biceps and Triceps brachii
Feet and Legs
A small motor unit is used for ___.
Crude muscle control
Accurate muscle control
A large motor unit is found in the _______.
Hands and Eyes
Gluteus maximus and Rectus femoris
Feet and Legs
Biceps and Triceps brachii
A large muscle unit is used for ______.
Crude muscle control
Accurate muscle control
The more motor units you recruit, the _______ the contraction.
Stronger
Weaker
What happens to your muscle to make them larger when you work out?
Muscle cells copy by mitosis to make new cells
Muscle cells add additional protein myofilaments and can generate more tension
Which phase of the muscle twitch is highlighted by the blue box?
Lag period
Muscle tension
Action Potential
Muscle contraction
Which phase of the muscle twitch is highlighted by the blue box?
Muscle relaxation
Muscle contraction
Lag period
Action Potential
Which phase of the muscle twitch is highlighted by the blue line?
Action Potential
Muscle tension
Lag period
Muscle contraction
Muscle relaxation
What would be the stimulus in this graph?
Calcium
ATP
Potassium
Action Potential
Why is there a lag period?
Action potential is needed to spread through the T-tubules and release Ca2+
Action potential is needed to spread through the T-tubules and release Ca2+, and for Actin and Myosin to interact
Action potential is needed to flip the myosin heads
Action potential is needed to add protein myofilaments to the muscles.
During muscle contraction, tension goes ____.
Up
Down
During muscle relaxation, tension goes ______.
Up
Down
More tension =_________.
A stronger contraction
A stronger action potential
Complete tetanus
Incomplete tetanus
If there are more action potentials more often, the contraction gets ________.
Stronger
Weaker
Longer
Shorter
Which phase of the muscle contraction is highlighted by the red line?
Incomplete Tetanus
Complete Tetanus
Contraction
Relaxation
What happens to the muscle tension when the sarcomere is too squashed?
Maximum tension
No tension at all
Isotonic contraction
Isometric contraction
What happens to the muscle tension when the sarcomere is too stretched?
No tension at all
Maximum tension
Isotonic contraction
Isometric contraction
What happens to the muscle tension when the sarcomere is "just right"?
No tension at all
Maximum tension
Isotonic contractions
Isometric contraction
In isotonic contractions the muscle _______ tension, and ______ get shorter.
generates, will not
generates, will
does not generate, will not
does not generate, will
In isometric contractions the muscle _______ tension, and ______ get shorter.
generates, will not
generates, will
does not generate, will
does not generate, will not
The source of energy during the first 6 seconds of exercise is from ______.
The store of ATP within the cell
Regeneration of ATP using creatinine phosphate
Anaerobic respiration
Aerobic respiration
The source of energy during __________ of exercise is from the regeneration of ATP using creatinine phosphate.
The first 6 seconds
After 30-40 seconds
6-16 seconds
After 1 minute and many hours
The source of energy after 30-40 seconds of exercise is from ______.
The store of ATP within a cell
Regeneration of ATP using creatinine phosphate
Anaerobic respiration
Aerobic respiration
The source of energy after _______ of exercise is from aerobic respiration.
1 minute, and for many hours
the first 6 seconds
6-16 seconds
30-40 seconds
What does EPOC stand for?
Electric Power Optimization Curve
Enfermedad Pulmonar Obstructiva Cronica
Exercise- Post Excess Oxygen Consumption
Excess Post-exercise Oxygen Consumption
Why do we need extra O2 even after we finish exercising?
Rebuild ATP stores
Rebuild creatinine phosphate stores
Return calcium to the endoplasmic reticulum
Rebuild stores of glycogen
Get rid of waste products
What is the function of the M-line?
It is the attachment site for the thick filaments
It is the attachment site for the thin filaments
It is the attachment site for the Z-line
It is the attachment site for the triad
In the 3D cell, each thick myofilament is surrounded by _____ thin myofilaments.
5
4
3
6
A neuron meets a muscle at the ________________ junction.
Axon terminalic
Axon
Neuromuscular
Synaptic
