Which blood vessels have valves to prevent backflow? MCQ with Answer and Explanation

Explanation:
Gel electrophoresis is a widely used technique to separate charged molecules, primarily DNA, RNA, or proteins, in an electric field through a gel matrix (usually agarose for DNA). DNA fragments are separated based on their size (length in base pairs). Smaller fragments move faster and further through the gel than larger ones. The separated DNA bands are visualized using ethidium bromide and UV light.

Explanation:
Aerenchyma is a specialized parenchyma tissue with large intercellular air spaces, providing buoyancy and facilitating gas exchange in aquatic plants. It also helps in oxygen transport to submerged roots. Sclerenchyma is supportive, collenchyma flexible support, xylem water-conducting.

Explanation:
Genotype is the set of alleles an individual possesses for a particular gene or trait (e.g., TT, Tt, tt). Phenotype is the observable characteristic. Karyotype is the chromosome complement.