Answer:
Helper T cells are arguably the most important cells in adaptive immunity, as they are required for almost all adaptive immune responses. They not only help activate B cells to secrete antibodies and macrophages to destroy ingested microbes, but they also help activate cytotoxic T cells to kill infected target cells.
Explanation:
Helper T cells become activated when they are presented with peptide antigens by MHC class II molecules, which are expressed on the surface of antigen-presenting cells (APCs). Once activated, they divide rapidly and secrete cytokines that regulate or assist the immune response.
Answer:
nonsense mutation
Explanation:
In DNA, the uracil (U) is replaced by thymine (T). If a change in the DNA sequence, or mutation, of a gene occurs that creates a stop codon, this is called a nonsense mutation.
Answer:
answer is d as m phase = cell growth
Answer:
Considering the formation of sedimentary rocks, the fossils in layer C are the oldest. Sedimentary rocks form in layers, with the oldest rock at the bottom. So, the fossils in layers A and B are newer than the ones in layer C. The fossils in layer A are the newest fossils
Explanation:
D.
homeostasis is how the body regulates your body temperature to keep it normal :)