FRIDAY: SI MAKE-UP SESSION
6) The all-or-none response means that
A) all of the muscles in a region contract together.
B) when a muscle fiber contracts, it contracts completely.
C) all of the muscle fibers within a muscle contract together.
7) A muscle cramp is most likely due to lack of
A) ATP.
B) ADP.
C) actin.
D) myosin.
9) Glycolysis
A) refers to the process of anaerobic respiration.
B) can replace ATP in binding to myosin molecules during contraction.
C) acts as the only source of ATP in muscle tissue.
D) is only active during strenuous exercise.
10) Fast fibers
A) have high resistance to fatigue.
B) have a high concentration of myoglobin.
C) have many mitochondria.
D) contract quickly.
11) During activities requiring aerobic endurance,
A) glycogen and glycolysis are the primary sources of reserve energy.
B) oxygen debts are common.
C) most of the muscle's energy is produced in mitochondria.
D) fatigue occurs in a few minutes.
12) A person whose genetic makeup makes him or her a better marathon runner than a sprinter probably has
more ________ in his or her leg muscles.
A) fast fibers
B) intermediate fibers
C) slow fibers
D) dark fibers
13) The term used to describe muscular growth in response to usage is
A) multiple sclerosis.
B) muscular dystrophy.
C) atrophy.
D) hypertrophy.
E) myopathy.
14) Compared to skeletal muscle, smooth muscle
A) contracts faster.
B) relaxes faster.
C) contracts and relaxes faster.
D) contracts faster and relaxes more slowly.
E) contracts and relaxes more slowly.
15) Nonstriated, involuntary muscle is
A) cardiac.
B) red skeletal.
C) smooth.
D) white skeletal.
MATCH
1) Muscle hypertrophy (due to increase in fiber size)
2) May convert fast glycolytic fibers into fast
oxidative fibers
3) Myoglobin synthesis
4) Muscle capillaries
5) Increased number of mitochondria
6) greater endurance, strength, and resistance to
fatigue
7) Increased mitochondria, myofilaments, glycogen
stores, and connective tissue
A. Aerobic (Endurance) Excersise leads to:
B.Resistance excersise (Typically anaerobic)
results in
SMOOTH MUSCLE
Smooth Muscle Special Features
1) Stress-relaxation response:
–
–
–
Responds to stretch only briefly, then adapts to new length
Retains ability to contract on demand
Enables organs such as the stomach and bladder to
temporarily store contents
2) Length and tension changes:
–
Can contract when between ____ and ______its resting
length
3) Hyperplasia:
–
Smooth muscle cells can _______ and __________ their
numbers
Example:
• estrogen effects on uterus (growth) at puberty and
during pregnancy (to accommodate the fetus)
–
Peristalsis:
• Alternating contractions and relaxations of ____________muscle layers that mix and
__________ substances through the lumen of hollow organs
– Longitudinal layer contracts; organ _______and shortens
– Circular layer contracts; organ ___________ and elongates
 Step 1:
 Step 2:
 Step 3:
Step 4:
Step 5:
 LABEL THE ACTIN and MYOSIN FILLAMENTS:
-
A for Actin
M for Myosin
Contraction
• ery energy efficient (slow ATPases)
• Myofilaments may maintain a latch state for prolonged contractions
Relaxation requires:
• Ca2+ detachment from ______________
• Active transport of Ca2+ into SR and ECF
• ______________________of myosin to reduce myosin activity (myosin phosphatase)
24) Slow oxidative muscle fibers
A) are the muscle cells most involved in short-term activity such as sprinting.
B) are the largest and most powerful of the skeletal muscle fiber types.
C) contract rapidly and generate ATP anaerobically.
D) resist fatigue and contain large amounts of myoglobin.
27)Synaptic vesicles contain neurotransmitters that are released by ________ when the action potential arrives.
A) endocytosis
B) apoptosis
C) hydrolysis
D) sodium
E) exocytosis
29)A fascicle is
A) a group of muscle fibers and motor neurons.
B) a collection of myofibrils in a muscle fiber.
C) the belly of a muscle.
D) a group of muscle fibers that are all part of the same motor unit.
E) a group of muscle fibers that are encased in the perimysium.
30)Which of the following is NOT a property of the myosin head?
A. They form cross-bridges with the active sites of actin
B. They have a hinge region to bend and straighten
C. They bind to troponin
D. They have ATPase activity
31)The sarcolemma is the
A. Cell membrane of a muscle fiber
B. Cytoplasm of muscle cells
C. Structural and functional unit of the skeletal muscle cell
D. Contractile thread that extends the length of the muscle fiber
E. Protein strand composed of actin
32)What is the role of tropomyosin in skeletal muscles?
A. Tropomyosin is the name of the contracting unit
B. Tropomyosin serves as a contraction inhibitor by blocking the myosin binding sites on the actin molecules
C. Tropomyosin serves as a contraction inhibitor by blocking the actin binding sites on the myosin molecules
D. Tropomyosin is the receptor for the motor neuron neurotransmittier
8) An adult has more muscle mass than a child. How did that increase in muscle mass occur?
A) atrophy
B) dysplasia
C) hyperplasia
D) dystrophy
E) hypertrophy
9) Transverse tubules put A for this only
A) are actually tiny pockets of plasma membrane that extend into the muscle cell.
B) are filled with interstitial fluid.
C) prevent the spread of an action potential to the interior of a myofiber.
D) A and B are correct.
10) The sarcoplasmic reticulum of muscle tissue
A) stores Ca2+ ions required for muscle contraction.
B) is called rough endoplasmic reticulum in other tissues.
C) is part of the transverse tubule.
D) is a thread of protein running the length of the muscle cell.
11) Myofibrils
A) include contractile proteins which stabilize the structure of the sarcomere.
B) include the contractile proteins actin and myosin.
C) include regulatory proteins that keep thick and thin filaments in proper alignment.
D) include structural proteins that decrease the extensibility and elasticity of the myofiber.
12) Which of the following does NOT happen during a muscle contraction?
A) The myosin heads bind to actin.
B) The myosin heads pull the thin filaments toward the M line.
C) The sarcomere shortens.
D) The myofiber and the muscle itself shorten.
E) The thick and thin filaments shorten.
13) A contraction cycle
A) cannot begin until Ca2+ has bound to troponin.
B) cannot begin until the myosin-binding sites on actin are exposed.
C) cannot begin until Ca2+ has bound to tropomyosin.
D) A and B are correct.
E) B and C are correct.
14) Place the events of a contraction cycle in the order in which they occur:
1. ATP hydrolysis
2. detachment of myosin head from actin
3. power stroke
4. crossbridge formation
A) 1, 4, 3, 2
B) 1, 4, 2, 3
C) 1. 3, 4, 2
D) 1, 3, 2, 4
15) Repetition of the contraction cycle
A) requires the absence of ATP.
B) requires the presence of an adequate number of Ca 2+ ions.
C) requires the action of the ATPase found on actin.
16) All of the following is true of rigor mortis EXCEPT:
A) Ca2+ from the sarcoplasmic reticulum accumulates in the cytoplasm.
B) Ca2+ binds to troponin allowing crossbridges to form.
C) Myosin ATPase activity allows the contraction cycle to repeat indefinitely.
E) Muscles contract until proteolytic enzymes from the lysosomes digest crossbridges.
17) A neuromuscular junction (NMJ)
A) is the synapse of a motor neuron with a muscle fiber.
B) includes the synaptic end bulbs of the muscle fiber.
C) includes the motor endplates of the motor neuron.
D) uses Na+ as a neurotransmitter.
18) Place the events at the neuromuscular junction (NMJ) in the order in which they occur:
1. release of acetylcholine (ACh)
2. activation of ACh receptors on motor endplate
3. termination of ACh activity by acetylcholinesterase (AChE)
4. arrival of an action potential at the synaptic end bulb
5. diffusion of ACh across the synaptic cleft
6. opening of Na+ channels in the motor endplate
7. production of muscle fiber action potential
A) 4, 1, 2, 5, 6, 7, 3
B) 4, 1, 5, 6, 2, 7, 3
C) 4, 1, 5, 2, 6, 7, 3
19) How do muscle fibers produce ATP?
A) from creatine phosphate
B) through anaerobic cellular respiration
C) through aerobic cellular respiration.
D) A, B and C are correct.
20) Creatine phosphate *Bonus* Creatine phosphate is ONLY produced in SKELETAL MUSCLE*
A) is produced when ATP levels in a muscle cell are depressed.
B) production requires the activity of creatine kinase.
C) is much less plentiful in the cytoplasm than is ATP.
21) Aerobic cellular respiration
A) converts the pyruvate from glycolysis into CO2, H2O, heat and ATP.
B) occurs in the mitochondria.
C) requires O2, which can be obtained from hemoglobin or myoglobin.
D) is required for muscle activities lasting longer than one minute.
E) All of these are correct.
22) Oxygen debt (recovery oxygen uptake)
A) is the amount of O2 required by the body to convert glycogen into lactic acid.
B) is the amount of O2 required by the body to remove O 2 from myoglobin.
C) is the amount of O2 required by the body to recuperate from exercise.
23) Which of the following is true of a twitch contraction?
A) During a twitch, all fibers in a motor unit respond to an action potential in a motor neuron.
B) During its latent period, Ca2+ binds to troponin.
C) During its contraction period, Ca2+ is actively transported in the sarcoplasmic reticulum.
24) Slow oxidative muscle fibers
A) are the muscle cells most involved in short-term activity such as sprinting.
B) are the largest and most powerful of the skeletal muscle fiber types.
C) contract rapidly and generate ATP anaerobically.
D) resist fatigue and contain large amounts of myoglobin.
25) What is the relationship of exercise to skeletal muscle fibers?
A) Endurance exercise can transform some FG fibers into FOG fibers..
B) Strength training exercises can induce production of more filaments in FG fibers.
C) Exercise does not change the number of skeletal muscle fibers.
D) A, B and C are correct.
26)When acetylcholine binds to receptors at the motor end plate, the end plate membrane becomes MORE permeable to sodium/
/potassium/Calcium ions. (Pick best answer)
QUICK REVIEW QUESTIONS
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What are the two ways to classify muscle fibers? Speed of contraction and which pathway it makes ATP
Does slow twitch have slow or fast ATPase? Slow
Is slow or fast twitch the dark meat of chicken? Slow twitch
Which twitch is found in the lower limbs in sprinters? Fast Twitch
What is the overload principle? When you work harder because muscle has to adapt to the increased endurance
How many layers does smooth muscle have, and what are they? 2 layers …. Longitudinal and circular
What is peristalsis? Contractions and relaxations in smooth muscle
Which muscle tissue is striated? Skeletal
Caveolae is similar to what in the skeletal muscle? T tubules
What are T tubules? Indentations in the sarcolemma
What does self-excitatory for smooth muscles mean? They do not need an outside stimulus to cause depolarization
What replaces troponin/tropomyosin in smooth muscle? Calmodulin
Where are the active sites, the actin or myosin? Actin
What is another name for the presynaptic terminal? Motor neuron
What is ATP broken down to in the cross bridge cycle? ADP and a phosphate
Z disk to Z disk is called the? Sarcomere
Beginning of Chapter 10
17. What is the neurotransmitter? >>>ACH
18. What degrades ACH >>>> ACHase
19. Where does the action potential come down? >>> motor neuron
20. What is the ligand for the ligand gated sodium channels? >>> ACH
21. Why is resting membrane potential negative> proteins molecules, more potassium on inside than outside (potassium leak
channels)
22. Why is the outside more positive >> more sodium on the outside
23. Are the ion channels mostly specific or nonspecific >>> specific
24. Where are the two calcium channels or they ligand or voltage? Presynaptic terminal / Sarcoplasmic reticulum
25. Where are voltage gated sodium channels found? Along the sarcolemma
26. It’s not an AP until you reach? >>> threshold
27. What arrives on the troponin to move the tropomyosin >>> Calcium
28. Where does the calcium come from? >>> sarcoplasmic reticulum
29. How does the SR release calcium >>> voltage gated calcium channel
30. When calcium leaves the SR where does it go to (before binding to troponin)sarcoplasm
31. Why is it called sarcoplasm and not cytoplasm? dealing with skeletal muscle
32. Why does the myosin head have a lot of energy, does it do work? The heads have ATPases,yes
33. When ATPases break down ATP what forms > ADP and a phosphate
34. Where is activation located, and what does this exactly mean? NMJ, and AP along the sarcolemma
35. Is work done during muscle twitch? NO