Answer:
by the sarcoplasmic reticulum's calcium ion pumps
Explanation:
Rigor mortis or postmortem rigidity, is a state caused by chemical changes in the muscles that occur post mortem and cause the limbs of the corpse to stiffen.
This occurs because after death, there is no cellular respiration and consequently, no oxygen nor ATP (ATP is required for the muscle relaxation).
Calcium enters the cytosol after death because it is released due to the deterioration of the sarcoplasmic reticulum and due to the breakdown of the sarcolemma. Ca2+ ions activate the formation of actin-myosin cross-bridging necessary for the contraction. Muscles are unable to relax, because myosin heads continue to bind with the active sites of actin and there is no ATP to destabilize the myosin-actin bond.
Answer:
d) passage of a solute against its concentration gradient
Explanation:
When a solute is transported against its concentration gradient, the cells use metabolic energy. To move a substance from the region of its lower concentration to that of its higher concentration, the energy of ATP hydrolysis is utilized. These types of transport mechanisms are called active transports. If ATP hydrolysis is inhibited in a cell, it would not be able to perform the uphill movement of solutes due to the lack of any source of energy to drive the process.
Form follows function in cell biology states that the form and shape of the body is linked to the function of that structure. For proper functioning of a cell or tissue, the structure of the cell or tissue evolves with time. This proves that the form or shape and function works together i.e., they are inter-related. If the function changes then the structure also needs to change for ideal working of the body.
Answer: The answer is B
Explanation:
Cellular respiration harvest most chemical energy from converting oxygen to ATP. During cellular respiration, most ATP produced are generated by oxidative phosphorylation , which uses the energy released by redox reactions in the electron transport chain to male ATP. The electrons are finally passed to oxygen which is reduced to water.
<span><u>How does fossilized carbon get back into the atmosphere?</u>
</span>Fossilized carbon is coal. One major way it gets back into the atmosphere is by humans burning it in coal power plants. Carbon gets back into the atmosphere as carbon dioxide through the combustion of fossil fuels.
<span><span><u>How does a plant get nitrogen from the soil?</u>
</span></span>Plants take nitrogen from the soil<span> by absorption through their roots as amino acids, nitrate ions, nitrite ions, or ammonium ions.</span><span>
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