The scientist who introduced the binomial system of classification was: MCQ with Answer and Explanation

Explanation:
Plasmids are small, circular, extrachromosomal DNA molecules in bacteria widely used as cloning vectors in genetic engineering. Restriction enzymes are part of the bacterial immune system, found in bacteria and archaea, not viruses, protecting them against bacteriophages. Polymerase Chain Reaction (PCR) requires a thermostable DNA polymerase (like Taq) to synthesize new DNA strands. Thus, statements 1 and 3 are correct.

Explanation:
Pleiotropy is when one gene influences several distinct phenotypic characteristics. Example: sickle cell disease (mutant hemoglobin affects RBC shape, causing anemia, pain, organ damage). Polygenic traits involve many genes, codominance both alleles expressed, epistasis gene interaction.

Explanation:
Molecular oxygen (O₂) accepts electrons at the end of the electron transport chain, combining with protons to form water (metabolic water). Without oxygen, the chain backs up, stopping ATP production. This is why oxygen is vital for aerobic respiration. NAD⁺ and FAD are electron carriers, cytochrome c a component.