Pernicious anemia is caused by the deficiency of: MCQ with Answer and Explanation

Explanation:
Phycoerythrin is a red phycobiliprotein that masks chlorophyll in red algae (Rhodophyta). Phycocyanin is blue in cyanobacteria, fucoxanthin brown in brown algae. These accessory pigments allow light absorption at depths.

Explanation:
Genetic engineering involves the direct manipulation of an organism's genome, often used to create transgenic organisms that contain foreign DNA (transgenes) for desired traits. Cloning is the process of producing genetically identical copies of a biological entity, ranging from genes to entire organisms. Tissue culture (micropropagation) is widely used for the rapid, large-scale propagation of plants from small explants in a sterile medium; it is not exclusively or primarily used for animal cloning. Thus, statements 1 and 2 are correct.

Explanation:
Telomerase is a ribonucleoprotein enzyme that adds repetitive nucleotide sequences to the ends of chromosomes (telomeres), preventing them from shortening during DNA replication. It is highly active in germ cells, stem cells, and most cancer cells, granting them replicative immortality. In most normal somatic cells, telomerase is inactive, leading to gradual telomere shortening and cellular aging.