Which structure is common to both prokaryotic and eukaryotic cells? MCQ with Answer and Explanation

Explanation:
Vitamin K is a cofactor for γ-glutamyl carboxylase, which modifies glutamate residues in clotting factors, enabling calcium binding and coagulation.

Explanation:
Genes are specific sequences of DNA that code for proteins or RNA, and they are arranged linearly on chromosomes within the nucleus. DNA replication is semi-conservative, meaning each newly synthesized DNA molecule consists of one original parental strand and one newly synthesized strand, as proven by the Meselson-Stahl experiment. RNA is typically single-stranded, allowing it to fold into complex shapes and perform various functions, unlike the double-stranded DNA helix. Thus, statements 1 and 2 are correct.

Explanation:
Vitamin B₆ exists in three forms: pyridoxine, pyridoxal, and pyridoxamine. Its active form, pyridoxal phosphate (PLP), is a coenzyme in amino acid metabolism and neurotransmitter synthesis. Deficiency can cause peripheral neuropathy and anemia.