U.s energy information office
The answer to the following question is D) They reproduce quickly and take up little space
Answer;
-Endocytosis
Explanation;
-Endocytosis includes; phagocytosis, pinocytosis, and receptor mediated: Endocytosis brings substances into the cell, plasma membrane surrounds the substances to be taken in, encloses them in a membrane-bound sac (vesicle) and brings them into the cell
-Phagocytosis: endocytosis of large solid particles (“cell eating”)
-Pinocytosis: endocytosis of extracellular fluid that contains dissolved solutes (“cell drinking”)
-Receptor-mediated: highly selective, ligands bind to specific receptor proteins on the plasma membrane and are then taken into the cell
-Exocytosis: the reverse of endocytosis: substances are removed from the cell; vesicles fuse with plasma membrane and release their contents into the extracellular fluid; important in nerve cells to release neurotransmitter and secretory cells to release cell products (ex. digestive enzymes, protein hormones).
(A) Mitosis has occurred, where healthy eukaryotic cells divide to form new cells.
Answer;
-Skin cells do not need crystallin for their function.
-Skin cells have the crystallin gene but do not express it.
Explanation;
-The crystallin proteins are water-soluble structural proteins that occur in high concentration in the cytoplasm of eye lens fibre cells. It has also been identified in other places such as the heart, and in aggressive breast cancer tumors.
-The main function of crystallins at least in the lens of the eye is probably to increase the refractive index while not obstructing light. The skin cell does not make crystallin protein because the skin cells do not need crystallin for their function and also they have the crystallin gene but do not express it.
