5 Written questions
5 Matching questions
- Leading strand
- replication fork
- repetitive DNA
- x-ray crystallography
- a The new complementary DNA strand synthesized continuously along the template strand toward the replication fork in the mandatory 5'?3' direction.
- b The basic, bead-like unit of DNA packing in eukaryotes, consisting of a segment of DNA wound around a protein core composed of two copies of each of four types of histone.
- c A technique that depends on the diffraction of an X-ray beam by the individual atoms of a crystallized molecule to study the three-dimensional structure of the molecule.
- d A Y-shaped region on a replicating DNA molecule where the parental strands are being unwound and new strands are growing.
- e Nucleotide sequences, usually noncoding, that are present in many copies in a eukaryotic genome. The repeated units may be short and arranged tandemly (in series) or long and dispersed in the genome.
5 Multiple choice questions
- The tandemly repetitive DNA at the end of a eukaryotic chromosome's DNA molecule that protects the organism's genes from being eroded during successive rounds of replication. See also repetitive DNA.
- A discontinuously synthesized DNA strand that elongates by means of Okazaki fragments, each synthesized in a 5'3' direction away from the replication fork.
- A protein that breaks, swivels, and rejoins DNA strands. During DNA replication, topoisomerase helps to relieve strain in the double helix ahead of the replication fork.
- A linking enzyme essential for DNA replication; catalyzes the covalent bonding of the 3' end of one DNA fragment (such as an Okazaki fragment) to the 5' end of another DNA fragment (such as a growing DNA chain).
- A dense region of DNA in a prokaryotic cell.
5 True/False questions
deoxyribose → An enzyme that catalyzes the lengthening of telomeres in eukaryotic germ cells.
semiconservative model → Type of DNA replication in which the replicated double helix consists of one old strand, derived from the old molecule, and one newly made strand.
heterochromatin → Eukaryotic chromatin that remains highly compacted during interphase and is generally not transcribed.
euchromatin → The complex of DNA and proteins that makes up a eukaryotic chromosome. When the cell is not dividing, chromatin exists in its dispersed form, as a mass of very long, thin fibers that are not visible with a light microscope.
Mismatch repair → The cellular process that uses specific enzymes to remove and replace incorrectly paired nucleotides.