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.
B is the correct answer because none of this that you put are testable.
Answer:
phototropism
Explanation:
Phototropism is the phenomenon that is causing the bean seedling to bend as shown.
Phototropism is known to be the growth of a plant or an organism in response to a light stimulus. This means that plants or organisms grow in the direction of the light. From the image shown, we will discover that the bean seedling is bending towards the direction of the sunlight.
This phenomenon usually occur in plants but it can also occur in organisms in fungi.
When the plants grow towards the direction of sunlight, it is known as positive phototropism while when the plants move away from the direction of sunlight, it is known as negative phototropism (skototropism).
Answer:
Trypsin cuts at lysine and arginine amino acid residues at the carboxyl end. Chymotrypsin cuts at tryosine , phenylalanine, and tryptophan amino acid residues at the carboxyl end.
Explanation:
Trypsin and chymotrypsin are known as proteolytic enzymes which are actively involved in the digestive system. They are both secreted by the pancreas and are majorly involved in the breakdown of protein in the small intestine.
Trypsin cuts at lysine and arginine amino acid residues at the carboxyl end. Chymotrypsin cuts at tryosine , phenylalanine, and tryptophan amino acid residues at the carboxyl end.