Muscles: Skeletal

1. What are the three types of muscle? The mechanism of contraction is similar between all three types.

1) red 2) white 3) yellow

1) skeletal (striated)cardiacsmooth
2) The mechanism of muscle contraction is similar between all three types.

Muscles are typically classified into three types: skeletal (striated), cardiac, and smooth. Despite their different functions and locations in the body, the mechanism of muscle contraction is similar across all three types.

Explanation

Muscles are typically classified into three types: skeletal (striated), cardiac, and smooth. Despite their different functions and locations in the body, the mechanism of muscle contraction is similar across all three types.

2. The muscles of the skeletal system are part of which function of the nervous system??

Sensory Input

Regulation

Motor Output!!!!

Integration

The muscles of the skeletal system are controlled by the nervous system through the motor output function, which involves sending signals from the brain and spinal cord to the muscles to initiate movement.

Explanation

The muscles of the skeletal system are controlled by the nervous system through the motor output function, which involves sending signals from the brain and spinal cord to the muscles to initiate movement.

3. What is the arrangement of the sarcomere?

- composed of myosin and actin filaments!!- The Z-line anchors thin filaments- H zone is the middle, where there are no myosin heads- A band is where there are actin filaments and myosin- I band is where there are only actin filaments; between Z-line
this image from slide 4 should clarify the structural appearance for you!!

- H zone is where there are myosin heads

- Composed of only myosin filaments

- The Z-line anchors thick filaments

The sarcomere is actually composed of both myosin and actin filaments, with the Z-line anchoring thin filaments. The H zone is located in the middle without myosin heads, while the A band consists of both actin and myosin filaments. The I band specifically contains actin filaments with no myosin, and it is located between Z-lines.

Explanation

The sarcomere is actually composed of both myosin and actin filaments, with the Z-line anchoring thin filaments. The H zone is located in the middle without myosin heads, while the A band consists of both actin and myosin filaments. The I band specifically contains actin filaments with no myosin, and it is located between Z-lines.

4. How do the structures of the muscle come together?

Myoglobin and elastin make up sarcomeres, which make up myofibrils, which make up muscle fibers, which make up bundles of muscle fibers.

Actin and myoglobin make up sarcomeres, which make up myofibrils, which make up muscle fibers, which make up bundles of muscle fibers.

Myosin and actin make up sarcomeres |sarcomere makes my myofibril |Myofibrils make up a muscle fiber (cell) |Bundles of muscle fibers make up the muscular tissue (the bicep in the pic from slide 4)

Actin and elastin make up sarcomeres, which make up myofibrils, which make up muscle fibers, which make up bundles of muscle fibers.

5. How does muscle contraction work in relation to the myosin-actin interactions involved?

Look at slide 6

A. through the release of neurotransmitters

D. look at slide 10

B. by the binding of ATP molecules

C. as a result of calcium ion release

The correct answer to the question is to refer to slide 6, which likely contains information relevant to myosin-actin interactions and muscle contraction. Option A, the release of neurotransmitters, is not directly related to myosin-actin interactions, hence incorrect. Option B, the binding of ATP molecules, while part of muscle contraction process, does not directly answer the question specific to myosin-actin interactions. Option C, calcium ion release, is an important step in muscle contraction but is not directly addressing the myosin-actin interactions aspect mentioned in the question. Option D, look at slide 10, is deliberately given as an incorrect answer as the correct reference point is slide 6.

Explanation

The correct answer to the question is to refer to slide 6, which likely contains information relevant to myosin-actin interactions and muscle contraction. Option A, the release of neurotransmitters, is not directly related to myosin-actin interactions, hence incorrect. Option B, the binding of ATP molecules, while part of muscle contraction process, does not directly answer the question specific to myosin-actin interactions. Option C, calcium ion release, is an important step in muscle contraction but is not directly addressing the myosin-actin interactions aspect mentioned in the question. Option D, look at slide 10, is deliberately given as an incorrect answer as the correct reference point is slide 6.

6. How does muscle contraction impact the shape of the sarcomere and what generally occurs?

The contraction of the sarcomere is solely due to the passive diffusion of ions across the cell membrane.

Sarcomere expands and the Z-line shifts outward, leading to relaxation.

Myosin head hyrolyze ATP as an energy source for moving the thin filaments (actin) inwardthe Z-line shifts inward to the center of the sarcomere and the as each of the 100,000 plus sarcomere of a muscle cell strinks, you get a contraction!!!

Actin filaments move outward without any energy consumption, causing elongation of the sarcomere.

During muscle contraction, the myosin head hydrolyzes ATP to move actin filaments inward, resulting in the shortening of the sarcomere. This process causes the Z-line to shift towards the center, leading to muscle contraction.

Explanation

During muscle contraction, the myosin head hydrolyzes ATP to move actin filaments inward, resulting in the shortening of the sarcomere. This process causes the Z-line to shift towards the center, leading to muscle contraction.

7. When the ATP in your muscles are used up, what condition are you most likely going to develop?

Rigor mortis

Diabetes

Asthma

Muscular dystrophy

When ATP in muscles is used up, it leads to rigor mortis, a condition characterized by stiffness in the muscles after death.

Explanation

When ATP in muscles is used up, it leads to rigor mortis, a condition characterized by stiffness in the muscles after death.

8. How does Calcium regulate Muscle Contraction?

Calcium inhibits the release of acetylcholine at the neuromuscular junction.

Calcium activates ATP production, leading to muscle relaxation.

Calcium directly binds to myosin, causing muscle contraction.

The myosin binding site on actin is blocked by tropomyosinin the relaxed muscle. When calciumbinds to troponin the tropomyosin shifts, exposing the binding site on actin.
Note: Calcium binds to troponin when calcium levels are high and this is regulated by the nervous system, because the nervous system regulate calcium levels in muscle fibrils

Calcium regulates muscle contraction by binding to troponin, not directly to myosin. It does not inhibit acetylcholine release or activate ATP production for muscle relaxation.

Explanation

Calcium regulates muscle contraction by binding to troponin, not directly to myosin. It does not inhibit acetylcholine release or activate ATP production for muscle relaxation.

9. Can muscle cells generate action potentials? What type of ion channels are on the plasma membrane of muscle fibers? Is each muscle in contact with a motor neuron? Y/N.

No, voltage-gated channels, Yes.

Yes, ligand-gated channels, No.

Yes

voltage-gated channels
Yes!!

No, ligand-gated channels, No.

Muscle cells can generate action potentials through voltage-gated channels on their plasma membrane, and each muscle is indeed in contact with a motor neuron for movement coordination.

Explanation

Muscle cells can generate action potentials through voltage-gated channels on their plasma membrane, and each muscle is indeed in contact with a motor neuron for movement coordination.

10. How do the muscle and nervous systems work together to bring about a contraction?

Look at you all done with muscles and shit!!***Pat yourself on the back because you only have three more lectures left!!****

The muscle system works independently of the nervous system.

The nervous system controls the contraction of bones, not muscles.

Contraction in muscles is solely due to external stimuli and has no connection to the nervous system.

The correct answer humorously acknowledges the completion of the topic on muscles and the nervous system. In reality, the nervous system sends signals to muscles, triggering contractions. This interaction is essential for movement and various bodily functions.

Explanation

The correct answer humorously acknowledges the completion of the topic on muscles and the nervous system. In reality, the nervous system sends signals to muscles, triggering contractions. This interaction is essential for movement and various bodily functions.