DNA Replication and Cell Cycle final

These flashcards cover the key vocabulary and concepts related to DNA replication and the cell cycle as presented in the lecture notes.

Cell Cycle

An ordered sequence of events where cells grow, duplicate DNA, and divide.

Semi-conservative replication

A model where each new DNA molecule contains one parental strand and one newly synthesized strand.

Replication fork

A Y-shaped region where DNA is unwound and new strands are synthesized.

Leading strand

The strand synthesized continuously toward the replication fork.

Lagging strand

The strand synthesized discontinuously away from the replication fork.

Okazaki fragments

Short DNA fragments synthesized on the lagging strand.

Topoisomerase

An enzyme that cuts DNA, relieves tension, and reseals it.

DNA polymerase III

The main enzyme that synthesizes new DNA by adding nucleotides to the 3’ end.

Telomers

Repetitive DNA sequences at chromosome ends that protect genetic material.

Mismatch repair

A mechanism that corrects incorrectly paired DNA bases.

Cytokinesis

The process in which the cytoplasm of a parental cell is divided into two daughter cells.

Replication bubble

The unwound region of DNA where replication is actively occurring.

Single-strand binding proteins (SSBs)

Proteins that stabilize unwound DNA strands and prevent re-annealing.

Exonuclease activity

The removal of nucleotides from the ends of DNA or RNA.

Deamination

Conversion of cytidine to uridine, causing potential mutations.

Non-homologous end joining

A fast but error-prone repair process that directly joins DNA ends.

Homologous recombination

An accurate DNA repair process that uses a sister chromatid as a template.

Prophase

The stage in mitosis where chromosomes condense and the spindle apparatus begins to form.

Anaphase

The stage in mitosis where sister chromatids are pulled apart to opposite poles.

Nucleases

Enzymes that cut damaged DNA to facilitate repair.

Replication diagram

Illustration showing the process of DNA unwinding, strand separation, and nucleotide addition.