T cells
The immune response to a transplanted organ consists of both cellular (lymphocyte mediated) and humoral (antibody mediated) mechanisms. Although other cell types are also involved, the T cells are central in the rejection of grafts. The rejection reaction consists of the sensitization stage and the effector stage.
Answer:
Changes occurs in the environmental conditions directly affect carrying capacity of the ecosystem.
Explanation:
Carrying capacity of the ecosystem refers to the capacity of the environment which adjust plants and animals in a specific atmospheric condition. Suppose in harsh winter, the temperature of the ecosystem is very low which is unbearable for most of the plant and animal species, so very low number of plants and animals are able to live in that environment. In the ecosystem where the winter is harsh and the spring is cold, the population of living organism are more decreasing. If the ecosystem has Harsh winter, Cold spring, and Hot summer, this type of environment hold very low number of living species due to high variation in the environment.
DNA, is like a blueprint of biological guidelines that a living organism must follow to exist and remain functional.
RNA, helps carry out this blueprint's guidelines.