Explanation:
There are several types of antibodies and antigens, and each antibody is capable of binding only to a specific antigen. ... Antigens are bound to antibodies through weak and noncovalent interactions such as electrostatic interactions, hydrogen bonds, Van der Waals forces, and hydrophobic interactions.
Antibodies attach to a specific antigen and make it easier for the immune cells to destroy the antigen. T lymphocytes attack antigens directly and help control the immune response. They also release chemicals, known as cytokines, which control the entire immune response.
Among the given choices, the only positive effect that may be thought off with the increase in level of CO2 in the atmosphere is the increase of plant growth. Carbon dioxide is an essential compound in the photosynthesis of plants. Therefore, the answer should be letter C.
Answer: The correct options are statement first and fourth that is -
It is synthesized toward the replication fork and it is synthesized in the 5′ to 3′ direction.
Leading strand in DNA is the strand of new DNA being synthesized in the same direction where the replication fork is moving. The movement of replication fork allows the access of template for the new DNA.
The DNA synthesis is continuous in the leading strand. It is synthesized in the 5' to 3' as DNA synthesis always takes place in this direction. This is because dNTP ( deoxyribonucleoside triphosphate) provides free 3' OH group where new dNTP can be added by the enzyme DNA polymerase.
The answer is nitrogen fixation.
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