Answer:
Self-antigens are not recognized and attacked by the T cells.
Explanation:
In immunology, the antigens are those substances which are bound by the antibodies. The antigens can be originated from within the bodies, known as self antigens or from outside the body, known as non-self antigens. The immune system identifies and attacks non-self invaders or the foreign harmful objects present in the body. It does not attack the self-antigens under the normal conditions. This is due to the negative selection of T cells of the thymus.
Answer: Option A is correct. They eat consumers which ate plants, which absorb it from soil.
Explanation:
Carnivores get nitrogen from the food they eat or consuming nitrogen from the small insects trapped in plant. They eat consumers which in turn eat plants and absorb nitrogen from the soil.
Answer: B (GTP serves as the energy input for AMP synthesis from IMP)
Explanation:
In the de novo synthesis of purine nucleotide, IMP represents a branch point for purine biosynthesis. IMP can be converted to either AMP or GMP.
The formation of AMP from IMP requires GTP; similarly formation of GMP requires ATP. The conversion of IMP to either AMP or GMP is highly regulated – AMP and GMP inhibits their own formation by feedback inhibition of adenlyosuccinate synthetase and IMP dehydrogenase.