Consider statements about human anatomy: 1. The femur is the longest bone in the body. 2. The stapes is the smallest bone in the body. 3. The hyoid bone is attached to another bone by a joint. Which are correct? MCQ with Answer and Explanation

Explanation:
Matthew Meselson and Franklin Stahl, in 1958, used density gradient centrifugation of E. coli grown in N¹⁵ medium to prove that DNA replication is semi-conservative: each new DNA molecule consists of one old and one new strand. Watson and Crick proposed the double helix, Hershey-Chase confirmed DNA as genetic material, Chargaff formulated base pair rules.

Explanation:
The pituitary, located at the base of the brain, controls many endocrine glands via its hormones, earning the name 'master gland'. Insulin is from pancreas; it is connected to hypothalamus by infundibulum.

Explanation:
Human somatic cells are diploid, containing 23 pairs of chromosomes (22 pairs of autosomes and 1 pair of sex chromosomes). The presence of the Y chromosome determines male sex (XY), while its absence results in female sex (XX). Mutations are random changes in DNA; while some are harmful, many are neutral, and some can be beneficial, providing the genetic variation necessary for evolution. Thus, statements 1 and 2 are correct.