LEHNINGER PRINCIPLES OF BIOCHEMISTRY
2026 ASSESSMENT SCRIPT DETAILED
RESPONSES COMPREHENSIVE REVIEW
◉ Chromosomes.
Answer: Contain genes and regulatory sequences involved in
replication, transcription, and other processes
◉ Genomic DNA and RNA molecules.
Answer: Orders of magnitude longer than viral particles or cells that
contain them
◉ Introns.
Answer: Noncoding sequences that interrupt genes in eukaryotic
cells
◉ Exons.
Answer: Coding segments of genes separated by introns
◉ Human genomic DNA.
Answer: Less than 1.5% encodes proteins, with less than one-third
consisting of genes
, ◉ Transposons.
Answer: Nucleic acid parasites accounting for about half of the
human genome
◉ Centromeres.
Answer: Special-function repetitive DNA sequences serving as
attachment points for the mitotic spindle
◉ Telomeres.
Answer: Repetitive DNA sequences located at the ends of
chromosomes
◉ Supercoiled DNA.
Answer: Underwound state of DNA that is either a closed circle or
bound to protein
◉ Linking number (Lk).
Answer: Topological parameter quantifying underwinding of DNA
◉ Superhelical density (σ).
Answer: Measure of underwinding, typically -0.05 to -0.07 for
cellular DNAs
2026 ASSESSMENT SCRIPT DETAILED
RESPONSES COMPREHENSIVE REVIEW
◉ Chromosomes.
Answer: Contain genes and regulatory sequences involved in
replication, transcription, and other processes
◉ Genomic DNA and RNA molecules.
Answer: Orders of magnitude longer than viral particles or cells that
contain them
◉ Introns.
Answer: Noncoding sequences that interrupt genes in eukaryotic
cells
◉ Exons.
Answer: Coding segments of genes separated by introns
◉ Human genomic DNA.
Answer: Less than 1.5% encodes proteins, with less than one-third
consisting of genes
, ◉ Transposons.
Answer: Nucleic acid parasites accounting for about half of the
human genome
◉ Centromeres.
Answer: Special-function repetitive DNA sequences serving as
attachment points for the mitotic spindle
◉ Telomeres.
Answer: Repetitive DNA sequences located at the ends of
chromosomes
◉ Supercoiled DNA.
Answer: Underwound state of DNA that is either a closed circle or
bound to protein
◉ Linking number (Lk).
Answer: Topological parameter quantifying underwinding of DNA
◉ Superhelical density (σ).
Answer: Measure of underwinding, typically -0.05 to -0.07 for
cellular DNAs