The pigment that is the primary photosynthetic pigment in cyanobacteria is: MCQ with Answer and Explanation

Explanation:
Edward Jenner developed the first successful smallpox vaccine (1796). Pasteur invented pasteurization and rabies vaccine, not penicillin. Fleming discovered penicillin. Hooke coined the term 'cell' but did not discover bacteria; Leeuwenhoek observed bacteria. Thus, the correct match is Jenner - smallpox vaccine.

Explanation:
The Haversian canal (central canal) is the core of the osteon (Haversian system) in compact bone. It runs parallel to the long axis of the bone and contains the blood vessels (arterioles, venules, capillaries), nerve fibers, and lymphatic vessels that supply the bone tissue. The concentric lamellae surround this canal. Osteocytes are housed in lacunae between the lamellae, and red bone marrow is found in the medullary cavity of long bones or the spaces of spongy bone.

Explanation:
A food chain is a linear sequence illustrating the transfer of energy and matter from one organism to another through consumption. A food web is a complex, interconnected network of multiple food chains, representing the realistic, multiple feeding relationships in an ecosystem. The pyramid of energy, which shows the amount of energy available at each trophic level, is always upright, never inverted, because energy is lost as heat at each transfer according to the 10% law. Thus, statements 1 and 2 are correct.