Answer:
CD4 on the surface of helper T-cells.
Explanation:
MHC class II ( major histocompatibility complex) molecules are processed from the exogenous source. The presentation of antigen on cells are important for the adaptive immune response.
MHC class II interact with CD 4 present on the surface of T helper cells. This interaction is important for the generation of an immune response. Helper T cells can release cytokines and can perform phagocytosis.
Thus, the correct answer is option (C).
Choice C. Educated guess or a prediction that can be tested, based on limited evidence.
Answer:
4
Explanation:
Because the mean time taken to turn from blue/black to orange/brown (in minutes) was the shortest, showing that the rate of reaction was the highest.
Answer:
gene flow
Explanation:
Gene flow, in simple terms, is a transfer of gene from one population to another. Also called as migration, where there is movement of individuals, and the genetic material they carry from one population to another. It also involves successful breeding of these individuals in their new locations. When people with sickle cell anemia were brought into the US, transfer of the gene responsible for sickle cell disease changed the frequency of the sickle cell allele in overall US population.