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Art [367]
3 years ago
13

When did life start?

Biology
2 answers:
Yakvenalex [24]3 years ago
8 0
At the start of life...
RideAnS [48]3 years ago
3 0
In the mid 1hondreds
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The following are the steps for B-cell activation. The steps are in an incorrect order.
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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.

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its interneurons

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If a part of a DNA molecule has the nitrogen base sequence ATG, in the complementary part of the other DNA molecule would have w
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