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:
65536 cells
Explanation:
starting from 1 cell at zero minutes there will be 1 (2^0) cell; 2^0 = 1
after 15 minutes there will be 2 (2^1) cells
after another 15 minutes ( 30 min) there will be 4 ( 2²) cells
after another 15 minutes ( 45 min) there will be 8 (2³) cells
after n number of 15 minutes there will be (2^n) cells
calculate number of 15 minutes in 4 hours
4 hours = 4 × 60 minutes
number ( n) of 15 minutes in 4 hours = (4 × 60 minutes) / 15 minute = 16
using the formula above and substitute 16 for n in the formula
Number of cells = 2 ^n = 2^16 = 65536 cells
The outer core<span> of the Earth is a fluid layer about 2,300 km thick and composed of mostly iron and nickel. It that lies above Earth's solid inner </span>core<span> and below its mantle. </span>
Answer:
Atoms combine when their electrons are shared or transferred
As the population of rabbits goes up, the coyote population rises shortly after. Between 1995 and 2000, the rabbit population began to drop drastically. The coyotes, having no constant food source, began to drop in numbers shortly after.
