In C3 plants, the primary CO₂ acceptor is: MCQ with Answer and Explanation

Explanation:
Primary productivity is the rate at which autotrophs (producers) convert solar energy into chemical energy (biomass) through photosynthesis. Secondary productivity is the rate at which heterotrophs (consumers) assimilate food to create new organic matter (biomass). Decomposition is a biological process carried out by microbes, and its rate is highly dependent on environmental factors like temperature, moisture, and oxygen availability; warmer temperatures generally increase decomposition. Thus, statements 1 and 2 are correct.

Explanation:
Kala-azar (visceral leishmaniasis) is caused by the protozoan Leishmania donovani, transmitted by sandfly bite. Tetanus is bacterial (Clostridium tetani), tuberculosis bacterial (Mycobacterium tuberculosis), measles viral. Protozoan diseases include malaria, amoebiasis, sleeping sickness, giardiasis. Kala-azar causes fever, weight loss, splenomegaly, and is endemic in parts of India.

Explanation:
Genes are specific sequences of nucleotides that serve as the fundamental units of heredity, and in all cellular organisms, they are made of DNA (deoxyribonucleic acid). Chromosomes are thread-like structures composed of DNA and proteins, and they are located within the nucleus of eukaryotic cells. DNA is the genetic material in all cellular organisms; RNA serves as the genetic material only in some viruses, not in cells. Thus, statements 1 and 2 are correct.