Answer: D. Heat
Explanation : Water Vapor is a source of warmth, since the heat that is radiated from Earth is absorbed by the water vapor. This is why greenhouses use water vapor as well.
Answer:
the element oxygen , represented by the symbol o, is classified as a pure substance
Answer:
Relative to prokaryotic cells, eukaryotic cells are usually larger and more complex.
Answer:
4. B cells become activated by interacting with helper T cells.
1. B cells display antigens in MHC class II receptors on the cell surface.
2. Antibodies released by plasma cells bind to the antigen so they will be destroyed by other cells of the immune system.
3.B cells rearrange their DNA to create a unique B-cell receptor.
5. B cells undergo clonal expansion.
6. B cells digest antigens that bind to the antibodies on their surface.
Explanation:
B-cells get activated by interacting with helper T cells when they bind to the antigen to receptors i.e (MHC class II receptors on the cell surface) on the surface of the cell. Series of activities such as release by plasma cells which cause rearrangement of B cells causes the cell to divide and proliferate. The process through which daughter cells arise from a parent cell called clonal expansion.
