Unit 5.1: Chromosomes, Cell Cycle, and Replication

Flashcards covering key concepts in chromosomes, the cell cycle, and DNA replication.

Prokaryotic Cells

Cells that are smaller, simpler, and lack a nucleus and specialized membrane-bound organelles.

Eukaryotic Cells

Larger, more complex cells with a defined nucleus and membrane-bound organelles.

Metabolism

The complex chemical reactions through which cells convert nutrients into energy.

Cell Cycle

The series of phases (M phase and Interphase) that a cell undergoes from division to division.

Gap 1 phase (G1)

Phase where the cell increases in size and prepares the necessary components for DNA synthesis.

S phase

Phase of the cell cycle where DNA is replicated in preparation for cell division.

Interphase

The phase of the cell cycle consisting of G1, S, and G2 phases before mitosis.

M phase

The phase of the cell cycle where mitosis and cytokinesis occur.

Chromosome

A complex of DNA-binding proteins and DNA; can be circular in prokaryotes and linear in eukaryotes.

Haploid

Having one of each type of chromosome.

Diploid

Having two of each type of chromosome.

Sister chromatids

The identical copies in a replicated chromosome.

Telomeres

The ends of linear chromosomes that do not contain genes and shorten during DNA replication.

Telomerase

An enzyme that extends telomeres in germ and embryonic cells, preventing their shortening.

RNA primase

An enzyme that builds short RNA primers for DNA polymerase to initiate DNA replication.

DNA Ligase

An enzyme that seals nicks in the DNA strand, joining Okazaki fragments on the lagging strand.

Replication Fork

The area where DNA is unwound to allow for replication, forming a Y-shaped structure.

Leading Strand

The strand of DNA that is synthesized continuously toward the replication fork.

Lagging Strand

The strand of DNA that is synthesized discontinuously away from the replication fork.

Okazaki Fragments

Short sequences of DNA synthesized on the lagging strand during DNA replication.