I believe the correct answer would be B. Semipermeable means that it allows certain substances to pass through, and certain other ones to not pass through. So given all of your options, I would say that B makes the most sense. Hope this helped!
-TTL
The answer is; D.
This can be called a secondary ecological succession because it includes the disruption of the former ecology, rather than the ecological succession from a new environment-primary succession. The invasive species outcompete the native species in their environment. In addition, the invasive species lack a natural predator hence spread unregulated in the environment.
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.
<span>antiemitic is the best choice </span>
