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:
water act as a reactant in light reaction.
Explanation:
Water undergo hydrolysis in presence of sunlight to form proton(H+) and hydroxyl ion(OH-) ion. The OH- ion liberates electron to reaction center of photosystem 1 thereby exciting the later .The excited photosystem then donates that extra electron to the primary electron acceptor and from the primary electron acceptor the electron moves through various electron carriers to generate ATP .
Basically water act as reducing agent in photosynthesis process.
Answer:
c. lobes
Explanation:
Brain lobes are divisions of the cerebral hemispheres, designated by the names of the surrounding cranial bones and covering them. The frontal lobe is located in the forehead region; the occipital lobe in the nape region; the parietal lobe in the upper central part of the head; and the temporal lobes in the lateral regions of the head above the ears.
Parietal, temporal and occipital lobes are involved in producing the perceptions resulting from what our sensory organs detect in the outer environment and the information they provide about the position and relationship to outer objects of different parts of our body.
Nitrogen is from the atmosphere is converted into nitrates by nitrogen fixing bacteria such as rhizobium which is found in the root nodules of leguminous crops
C) 1 and 4
hope it heps.........................
