In which cell organelle does the Krebs cycle take place? MCQ with Answer and Explanation

Explanation:
Mature human RBCs have a lifespan of approximately 120 days, after which they are phagocytosed by macrophages in the spleen and liver. They lack nuclei and organelles, thus cannot repair themselves. New RBCs are produced in the bone marrow at a rate of about 2 million per second. Erythropoietin stimulates RBC production.

Explanation:
Gene therapy involves correcting a genetic defect by introducing a functional gene into a patient's cells. The first clinical gene therapy was given in 1990 to a 4-year-old girl with Adenosine Deaminase (ADA) deficiency, a severe combined immunodeficiency (SCID) caused by a mutation in the ADA gene. The functional ADA gene was introduced into her lymphocytes using a retroviral vector.

Explanation:
In-situ (on-site) conservation involves the conservation of species in their natural habitats. National parks, wildlife sanctuaries, and biosphere reserves are examples of in-situ conservation. Ex-situ (off-site) conservation involves taking endangered species out of their natural habitat and placing them in special settings like zoological parks, botanical gardens, and seed banks for conservation and breeding.