Bio lecture 16 - Mitosis

Chromosome

A structure within cells that contains DNA and is responsible for genetic information storage and transmission during cell division. Packaged DNA molecules in a cell

Chromatin

a complex of DNA and proteins found in eukaryotic cells that condenses to form chromosomes during cell division. protein/DNA complex

genome

the complete set of genetic material in an organism, including all of its genes and non-coding sequences. All DNA in a cell

sister chromatid

the identical halves of a duplicated chromosome, joined together at the centromere. They separate during cell division.

centromere

a specialized sequence of DNA where the two chromatids appear most constricted

mitosis

the process of cell division that results in two genetically identical daughter cells, essential for growth and repair. separation of replicated chromosomes

cytokenesis

the final stage of cell division where the cytoplasm divides, resulting in two separate daughter cells.

M (mitotic) phase

the phase of the cell cycle that includes both mitosis and cytokinesis, leading to cell division.

interphase

the phase of the cell cycle that occurs between mitotic divisions, consisting of G1, S, and G2 phases, where the cell grows and DNA is replicated. NO DIVISION

g1 phase

the first subphase of interphase in the cell cycle, during which the cell grows, produces RNA, and synthesizes protein before DNA replication.

s phase

the subphase of interphase where DNA synthesis occurs, resulting in the duplication of chromosomes.

g2 phase

the second subphase of interphase in the cell cycle, following DNA synthesis, during which the cell prepares for mitosis by producing more proteins and organelles.

prophase

Mitosis is the beginning. Chromosomes condense, Mitotic spindle begins to form, pushing centrosomes away from each other. Centrosomes are pushed toward opposite poles of a cell by the lengthening of microtubules between them.

metaphase

Chromosomes settle midway between the two poles of the cell = the metaphase plate.

This alignment of the chromosomes at the “midline” defines metaphase. *this is an imaginary plate

anaphase

the defining moment of chromosome separation. Sister chromatids are suddenly separated from each other, and each is pulled toward the pole to which it is attached by spindle fibers. Each can now be considered a chromosome.

telophase

the final stage of mitosis, the process that separates duplicated genetic material into two identical daughter cells. Nuclear membrane reassembles and chromatin becomes less tightly coiled.

mitotic spindle

a machine that uses microtubules to pull apart sister chromatids during mitosis

centrosome

sites where microtubules of the mitotic spindle begin to form. duplicate during interphase, start adjacent and end up at opposite sides of the cell

kinetochore

a protein complex that assembles on the centromere DNA of each sister chromatid during mitosis. links microtubules to chromosomes.

metaphase plate

When/where chromosomes settle midway between the two poles of the cell

cleavage furrow

an indentation that appears on the surface of a dividing cell during cytokinesis. ANIMAL CELLS mainly also some protists. not plants

cell plate

a structure that forms in the center of the cell, separating the two daughter cells and eventually becoming the new cell wall. PLANT CELLS