Answer:
Letter B.
Explanation:
Aquaporins, also known as "water channels," are the main transport of water through the membranes of plant, animal, and bacterial cells. These channels allow the water to travel into and within cells and, at the same time, exclude the passage of ions and solutes.
What makes letter B the correct answer, is the form of transport and shape of the channel that allow water according to the osmotic gradient. In this model, letter A shows simple diffusion, while C and D seem to illustrate gated channels.
Breathing, moving blood throughout the body, and so forth.
The process of turning off and on of genes is known as gene regulation.
Explanation:
When the gene is turned on, it instructs the cells to construct a particular protein. The proteins are the molecules that build your body with collagen, tendons, and bones or keratin in your hair.
The gene regulatory proteins allow the individual genes of an organism to be turned on or off . in different cell types there are different selections of gene regulatory proteins. The patterns of the gene expression gives each cell its unique characteristics.
Each cell produces or turns on only a fraction of its genes. the remaining genes are repressed or turned off. this process is known as gene regulation. The signals from the environment or from other cells activate proteins called transcription factors.