Answer:
Secondary succession is the series of community changes which take place on a previously colonized, but disturbed or damaged habitat. Examples include areas which have been cleared of existing vegetation (such as after tree-felling in a woodland) and destructive events such as fires.
<span>When cells were first taken from Henrietta Lacks, she was suffering from cervix cancer. Henrietta Lacks was a woman whose cervix cancer cells were used as the source of the HeLa cell line nowadays used in medical research. During treatment for cervical cancer in 1951, the cells were taken without her knowledge. The cells were cultured by George Otto Gey who created the HeLa cell line.</span>
I believe the best answer is C.
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.
The respiratory system that allows for Gas Exchange happens between Alveolar Spaces and Capillaries
