Practice Questions

The total cross-sectional width of the standard B-form DNA double helix is 2.0 nm (20 A˚).

With 61 codons coding for 20 amino acids, most amino acids are specified by more than one triplet codon, making the code degenerate.

A gene includes its structural coding sequence alongside the regulatory elements required to turn its expression on or off.

RNA polymerase tracks along the DNA template strand to assemble ribonucleoside triphosphates into a complementary RNA molecule.

Pairing purines with pyrimidines preserves a constant 2 nm spacing, preventing structural bulges or pinches along the helix.

The genome encompasses the total collective repository of an organism's hereditary instructions stored within its nucleic acids.

A full 360∘ turn accommodates roughly 10 base pairs, meaning each step rotates the helix by an angle of approximately 36∘.

DNA replication is the semi-conservative duplication of the cellular genome, ensuring each daughter cell inherits a complete set of genes.

The TATA box is a critical promoter element situated upstream of the transcription start site, helping position RNA polymerase II.

The structural framework of the DNA strand is formed by a repeating chain of deoxyribose sugars linked by neutral phosphodiester groups.