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:
There are over 60, 000 species if trees; however, there are 101 different tree types.
Explanation:
Globally its over 60,065 species of trees but the question asked how many different types of trees are there and the answer is 101 according to www.homestratosphere.com
Answer:
respiration,photosynthesis
Explanation:
I'm not so sure the first blank is cellular respiration but I'm posive the second blank is photosynthesis:)
The DVD experiment worked to prove that spontaneous generation