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Answer: Mir Jafar
Answer:Similarly, the dielectric constant is also a ratio and is thus a dimens...
Answer:a) Metric units and SI units
Answer: the force that it exerts on the ground
Answer:1) Magnetic fields of the earth
Answer:1) Gravity
Answer:4) Silicon
Answer:2) opposite the sun
Answer:1) Self - induction
Answer:1) Bending of light rays when they enter from one medium to another med...
Answer:3) Violet is correct answer.
Answer:1) Marble.
Answer:4) Stainless steel
Answer:The correct answer is Area.
Answer:4) seismic wave is correct answer
Answer:3) battery
Answer:1) shorter wavelengths
Answer:2) Silicon
Answer:1) Exothermic reaction
Answer:1) Atom

Cytosolic Ca2+ causes muscle contraction by______

a. Binding to troponin

b. Binding to tropomyosin

c. Binding to myosin

d. Binding to actin

Muscle contraction is caused by_______

a. The shortening of actin filaments, caused by theATP-dependent action of myosin

b. The shortening of myosin filaments, caused by theATP-dependent action of actin

c. The sliding of myosin and actin filaments, caused by theATP-dependent action of myosin

d. The sliding of myosin and actin filaments, caused by theATP-dependent action of actin

When an action potential reaches a neuromuscular junction theresult is____

a. Acetylcholine binds to receptors on the sarcoplasmicreticulum, causing Ca2+ to flood the cytosol

b. Acetylcholine binds to receptors on the sarcolemma (muscleplasma membrane), causing depolarization of the sarcolemma

c. Ca2+ binds to receptors on the sarcolemma, causingdepolarization of the sarcolemma

d. Acetylcholine binds to troponin, allowing myosin to bind toactin

The step in the contraction cycle at which ATP binds to myosinis___

a. When myosin binds to actin

b. The “power stroke” when myosin slides the actin filamentalong

c. Just after the “power stroke”, in order to release myosinfrom actin

d. Immediately after Ca2+ enters the cytosol

Which of the following statements about the cytoskeleton istrue?

a. The cytoskeleton is made up of four types of proteinfilaments.

b. The bacterial cytoskeleton is important for cell division andDNA segregation.

c. Protein monomers that are held together with covalent bondsform cytoskeletal filaments.

d. The cytoskeleton of a cell can change in response to theenvironment.

Answer: option B
Answer: option B

can i get help in these questions. my answers 6)a 7)c 8)a 9)b 10)e 11)a 12)d- 13)c 14)a 15)b 16)e 17)a 18)d. im unsure of some answers but im wondering if you guys can check if im correct or wrong.thank you

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Answer:C) the motor neuron triggers an action potential at the neuromuscular j...
1. The striated appearance ofskeletal muscle is due to the
A. dark color of myosin.
B. multiple nuclei per fiber.
C. regular arrangement of filaments.
D. dense array of microtubules.
E. dense packing of ATP molecules.
Your Response:
2. How do muscle fibersshorten during contraction?
A. Individual protein filaments contract.
B. More cross-bridges are formed betweenfilaments.
C. Arrays of filaments overlap each other.
D. Protein filaments coil more tightly.
E. Subunits of protein polymers detach.
Your Response:
3. How do actin and myosinmolecules interact?
A. Globular myosin heads bind to actin filaments.
B. Globular actin heads bind to myosin filaments.
C. Other proteins connect the two.
D. Myosin filaments bend to connect to actin.
E. Actin filaments bend to connect to myosin.
Your Response:
4. When animals die, musclesstiffen in rigor mortis because
A. muscles cannot contract without ATP.
B. actin and myosin cannot bind without ATP.
C. actin and myosin cannot separate without ATP.
D. ATP is required for synthesis of proteinfilaments.
E. ATP forms cross-bridges between filaments.
Your Response:
5. Vertebrate skeletalmuscles are excitable cells because they
A. can be stimulated by ATP.
B. can be stimulated by an electric charge.
C. can secrete neurotransmitter.
D. possess voltage-gated sodium channels.
E. can attain a high level of activity.
Your Response:
6. Starting with the arrivalof an action potential at the neuromuscular junction, which of thefollowing is the correct order of events?
A. Calcium is released from the sarcoplasmic reticulum,an action potential travels down the T tubules, depolarizationspreads through the T tubule, and myosin binds actin.
B. An action potential travels down the T tubules,depolarization spreads through the T tubule, calcium is releasedfrom the sarcoplasmic reticulum, and myosin binds actin.
C. An action potential travels down the T tubules,depolarization spreads through the T tubule, calcium is taken up bythe sarcoplasmic reticulum, and myosin binds actin.
D. An action potential travels down the T tubules,depolarization spreads through the T tubule, ATP binds to myosin,and myosin binds actin.
E. A T tubule is depolarized, calcium is released fromthe sarcoplasmic reticulum, an action potential is created in themuscle cell, and myosin binds actin.
Your Response:
7. How does tropomyosincontrol muscle contraction?
A. It provides a bridge between actin and myosin.
B. It provides a site where ATP can be utilized.
C. Changes in its position expose actin
Answer: option b
Answer:B)cross bridges have actin binding sites that are normally covered by t...
Answer:depolarization of the T tubules causes calcium channels in the sacropla...
Answer: option 3

Answer: option C
Answer: option C
Answer: option D
Answer: option C
Answer: option A
Answer: option B

2. Within a single fiber, the tension developed during a twitch depends on:
a. Length of the thick filament
b. Duration of the stimulus
c. Amplitude of the action potential

d. Length of the sarcomeres prior to contraction

c. The speed the action potential is propagated throughout the muscle fiber

3. The two systems that directly control homeostasis:

a. Musculoskeletal and endocrine

b. Nervous and endocrine

c. Cardiovascular and nervous

4. There are 4 primary tissue types, which of these is not a primary tissue type:

a. Connective

d. Blood

b. Neural

e. Muscle

c. Epithelial

None of the above

There are more than two systems that control homeostasis

5. The muscle functional unit responsible for force production is the:

d. Sarcolemma

a. Sarcomere

e. Calcium

Motor unit


6. Choose the true statement(s):
a. Biarticular muscles only produce concentric contractions

b. During an eccentric contraction the muscle neither shortens nor lengthens

C. For a given muscle, it will produce its highest forces during a concentric contraction

d. The primary purpose of concentric contractions is fixation

e. The primary purpose of eccentric contractions is deceleration

7. Homeostasis is the condition in which the body maintains:

A. A dynamic state within an unlimited range, depending on circumstances

B. Static state with little deviation from preset points

C. A relatively stable internal environment, within limits

d. The lowest possible energy usage

8. Osteoclast precursor cells are:

a. Osteocytes

b. Osteoblasts

c. Osteogenic cells (stem cells)

d. None of the above

C. Leukocytes (white blood cells)

Answer: option C
Answer:D. When the myosin molecules of the thick filaments shorten, the muscle...
Answer: option C

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