The scientist who first successfully synthesized the gene for somatostatin (a hormone) in a bacterium, demonstrating the potential of recombinant DNA technology for producing human hormones, was: MCQ with Answer and Explanation

Explanation:
Fossils provide direct, tangible evidence of past life forms and evolutionary changes over geological time. Comparative anatomy (homologous/analogous organs), embryology (similar early stages), and molecular biology (DNA/protein sequence similarities) provide indirect evidence. Fossils show transitional forms like Archaeopteryx (between reptiles and birds).

Explanation:
The skin and mucous membranes form the first line of defense (innate immunity), acting as physical barriers that prevent pathogens from entering the body. White blood cells (leukocytes), including phagocytes and lymphocytes, are the cellular components of the immune system that identify, attack, and destroy pathogens. Antibiotics are drugs designed to kill or inhibit the growth of bacteria; they are completely ineffective against viruses, which lack the cellular machinery targeted by antibiotics. Thus, statements 1 and 2 are correct.

Explanation:
GHRH, from the hypothalamus, stimulates the anterior pituitary to secrete growth hormone. Somatostatin inhibits GH release. Dopamine inhibits prolactin.