Mitosis and Meiosis Flashcards

Study Notes

Binary fission is a method of asexual reproduction for prokaryotes, resulting in two genetically identical organisms, no nucleus involved.
Mitosis involves the division of a single nucleus into two identical nuclei, integral to the cell cycle's mitotic phase (M).

Chromosomes are threadlike gene carriers in eukaryotic nuclei, most visible during mitosis and meiosis; composed of chromatin (DNA and protein).
Chromatin refers to the diffuse form of DNA and proteins present when a cell is not dividing.
Sister chromatids are identical parts of a duplicated chromosome, linked at the centromere prior to mitosis.
The centromere is where sister chromatids are joined, appearing as a narrow waist, critical for spindle microtubule attachment during cell division.

Spindle fibers are crucial for dividing genetic material, forming during mitosis and meiosis to ensure equal chromosome distribution to daughter cells.
Centrioles are animal cell structures made of microtubule triplets arranged in a 9 + 0 pattern, playing a role in cell division.

Interphase is the longest phase of the cell cycle where the cell is not dividing, encompassing growth and preparation for mitosis.
G1 phase (Growth 1) entails cell growth and mRNA/protein synthesis for the next phases.
S phase (Synthesis) involves DNA replication, ensuring accuracy to prevent genetic abnormalities.
G2 phase is the second growth phase post-DNA replication, during which the cell prepares spindle materials.

Prophase marks the beginning of mitosis; chromatin condenses, sister chromatids become visible, and spindle formation starts while the nucleus remains intact.
Metaphase involves the alignment of duplicated chromosomes at an equidistant plane across the spindle.
Anaphase starts with the separation of sister chromatids, concluding when daughter chromosomes reach the poles.
Telophase is the final mitosis stage, forming daughter nuclei at each pole and usually occurring with cytokinesis.
Cytokinesis divides the cytoplasm, creating two distinct daughter cells, occurring alongside telophase.

The cell cycle includes interphase and the mitotic phase, marking the period from cell formation to division into daughter cells (G1, S, G2, M, and cytokinesis).