The technique of growing plants in nutrient-rich water without soil is known as: MCQ with Answer and Explanation

Explanation:
DNA polymerase catalyzes the formation of phosphodiester bonds between adjacent nucleotides, extending the new strand complementary to the template. Helicase unwinds DNA, ligase joins fragments, primase synthesizes RNA primer. In prokaryotes, DNA polymerase III is the main replicative enzyme.

Explanation:
Human Immunodeficiency Virus (HIV) specifically targets and destroys CD4+ T-helper cells, severely compromising the immune system and leading to AIDS. Tuberculosis (TB) is a bacterial infection caused by Mycobacterium tuberculosis, which primarily affects the lungs (pulmonary TB). Malaria is not caused by a virus; it is caused by a protozoan parasite of the genus Plasmodium, transmitted by the Anopheles mosquito. Thus, statements 1 and 3 are correct.

Explanation:
Adrenaline (epinephrine) from the adrenal medulla mediates the 'fight-or-flight' response, increasing heart rate, contractility, and blood pressure. Acetylcholine slows heart, insulin lowers glucose, melatonin induces sleep.