Cell Cycle and DNA Structure Flashcards

Vocabulary flashcards detailing the chronological phases of mitosis, cellular structures, and the biochemical components of DNA based on the lecture transcript.

Interphase

The preparation stage of the cell cycle.

Prophase

Stage where chromosomes condense (visible as $X$-structures), centrosomes move apart, and the nuclear envelope breaks down.

Metaphase

Stage where chromosomes align at the metaphase plate in the center of the cell, with spindle fibers (microtubules) attached.

Anaphase

Stage where sister chromatids separate and move towards opposite poles of the cell, pulled by spindle fibers.

Telophase

Stage where new nuclei form, the nuclear envelope reappears, and chromosomes decondense back into chromatin.

Cytokinesis

The process where the cell membrane divides the cytoplasm into two daughter cells, often marked by a cleavage furrow.

Centrosome

Organelles containing centrioles that move to opposite poles to organize the spindle fibers.

Spindle Fibers

Microtubules used to pull sister chromatids apart during mitosis.

Sister Chromatids

The two identical halves of a duplicated chromosome that separate during anaphase.

Gene

A segment of DNA that serves as the blueprint for producing a protein product.

Base Pairs

The paired nitrogenous bases in DNA consisting of $A-T$ (Adenine-Thymine) and $C-G$ (Cytosine-Guanine).

Kinetochore

A protein structure on the chromosome where spindle fibers attach.

Centromere

The region of a chromosome that joins sister chromatids and contains the kinetochore protein structure.

Sugar-Phosphate Backbone

The structural frame of the DNA double helix located on the outside of the nitrogenous bases.

Hydrogen Bonds

The chemical bonds that hold nitrogenous base pairs together in the DNA double helix.

Chromatin

The decondensed state of DNA that chromosomes return to during telophase.