1. If you were to watch muscle tissue contract: Under a light microscope, would you see...

1. If you were to watch muscle tissue contract:

Under a light microscope, would you see the muscle fibers get narrower, or the striations get thinner? Explain.
At the EM level, focusing on one sarcomere, you would be able to see a region of thick filaments overlapping two regions of thin filaments. Use the structure of the thick filaments to explain how ONE region of thick filaments is able to pull in microfilament in two opposite directions (both toward the center of the sarcomere)

Please answer question (a).

Expert Solution

Ans a- muscle fibers get narrower.

Each skeletal muscle fiber is a skeletal muscle cell. Within each muscle fiber are myofibrils—long cylindrical structures that lie parallel to the muscle fiber.The striated appearance of skeletal muscle tissue is a result of repeating bands of the proteins actin and myosin that are present along the length of myofibrils. Dark A bands and light I bands repeat along myofibrils, and the alignment of myofibrils in the cell causes the entire cell to appear striated or banded.

Each I band has a dense line running vertically through the middle called a Z disc or Z line. The Z discs mark the border of units called sarcomeres, which are the functional units of skeletal muscle. One sarcomere is the space between two consecutive Z discs and contains one entire A band and two halves of an I band, one on either side of the A band. A myofibril is composed of many sarcomeres running along its length, and as the sarcomeres individually contract, the myofibrils and muscle cells shorten.

During Muscle Contractions

Action potential in a motor neuron triggers the release of Ca2+ ions from the sarcoplasmic reticulum
Calcium ions bind to troponin (on actin) and cause tropomyosin to move, exposing binding sites for the myosin heads
The actin filaments and myosin heads form a cross-bridge that is broken by ATP
ATP hydrolysis causes the myosin heads to swivel and change orientation
Swiveled myosin heads bind to the actin filament before returning to their original conformation (releasing ADP + Pi)
The repositioning of the myosin heads move the actin filaments towards the centre of the sarcomere
The sliding of actin along myosin therefore shortens the sarcomere, causing muscle contraction.

From above discussion it is clear that muscle fibers get narrower.

gladiator answered 2 years ago

If you were to watch muscle tissue contract: a. Under a light microscope, would you see...

If you were to watch muscle tissue contract: a. Under a light microscope, would you see the muscle fibers get narrower, or the striations get thinner? Explain. b. At the EM level, focusing on one sarcomere, you would be able to see a region of thick filaments overlapping two regions of thin filaments. Use the structure of the thick filaments to explain how ONE region of thick filaments is able to pull in microfilament in two opposite directions (both toward...

You take a tissue sample from a wound. You look at it under the microscope and...

You take a tissue sample from a wound. You look at it under the microscope and see bacteria inside epidermal cells, surrounding the nucleus. Which of the following activities must have occurred to get the bacteria there? (Select all that apply) Group of answer choices Attachment Colonization Invasion Toxin production Replication Biofilm formation

What color would you see if you were to shine a beam of yellow light and...

What color would you see if you were to shine a beam of yellow light and a beam of cyan light at the same spot on a white wall? (Warmup: Explain your answer. Review: Explain your answer by describing what happens to the relevant primary color components of light from the time the lights leave their respective sources to the time they enter your eye, and how your eye interprets that light.)

How much detail, if any, can you see inside chloroplasts using the light microscope? Why?

Identify each type of muscle cell, their functions, locations, and describe how they look under microscope.

Describe what you can see under a microscope for each one. Frog blood smear Reptile blood...

Describe what you can see under a microscope for each one. Frog blood smear Reptile blood Trypanosoma lewisi blood smear rat iron hemosiderin TB reaction Human blood smear wright

Under anaerobic conditions, pyruvate is converted into lactate in vertebrate muscle tissue. This conversion allows the...

Under anaerobic conditions, pyruvate is converted into lactate in vertebrate muscle tissue. This conversion allows the muscles to continue carrying out glycolysis because Group of answer choices The decarboxylation of pyruvate to lactate regenerates NAD+, which maintains redox balance. The reduction of pyruvate to lactate regenerates NADH, which maintains redox balance. None of the other choices is correct. The decarboxylation of pyruvate to lactate regenerates NADH, which maintains redox balance. The reduction of pyruvate to lactate regenerates NAD+, which maintains...

The stages of mitosis were originally defined by cellular features observable through a light microscope.

The stages of mitosis were originally defined by cellular features observable through a light microscope. The six micrographs below show animal cells (lung cells from a newt) during the five stages of mitosis, plus cytokinesis. (Note that interphase is not represented in these micrographs.) In these images, the chromosomes have been stained blue, microtubules green, and microfilaments red.

1) When viewing a mixed culture of bacteria under a microscope, you notice that there is...

1) When viewing a mixed culture of bacteria under a microscope, you notice that there is significant diversity in their arrangements and shapes.Describe the types of bacterial cell arrangements and what determines the diversity in these arrangements.Explain why Bacilli are less varied in arrangement than cocci? (Minimum length : 150 words).

biochem question: At the pO2 in ACTIVE muscle tissue, would Mb or Hb be predicted to...

biochem question: At the pO2 in ACTIVE muscle tissue, would Mb or Hb be predicted to have the higher Kd value? Explain, correlating with function of the protein. Would a protein with only tertiary structure ever display cooperative binding?

Question