Mitosis Flashcards
Haploid Cells
Sperm and Egg Cells. 1n
n means
chromsomes
Complete DNA forms
tissue which becomes cells.
Mitosis is what type of production?
Asexual
Germ Cell
a cell containing half the number of chromosomes of a somatic cell and able to unite with one from the opposite sex to form a new individual; a gamete.
Process of Mitosis
Prophase Metaphase Anaphase Teleophase
Prophase
Nuclear envelope.
Starts to breakdown.
Polar opposite cells.
Centrosome.
The chromosomes condense into X-shaped structures that can be easily seen under a microscope.
Each chromosome is composed of two sister chromatids, containing identical genetic information.
The chromosomes pair up so that both copies of chromosome 1 are together, both copies of chromosome 2 are together, and so on.
At the end of prophase the membrane around the nucleus in the cell dissolves away releasing the chromosomes.
The mitotic spindle, consisting of the microtubules and other proteins, extends across the cell between the centrioles as they move to opposite poles of the cell.
Metaphase
Chromosomes start to align.
The chromosomes line up neatly end-to-end along the centre (equator) of the cell.
The centrioles are now at opposite poles of the cell with the mitotic spindle fibres extending from them.
The mitotic spindle fibres attach to each of the sister chromatids.
Anaphase
Fibres pull the chromosomes.
The sister chromatids are then pulled apart by the mitotic spindle which pulls one chromatid to one pole and the other chromatid to the opposite pole.
Telophase
Cell membrane breaks froming two cells.
Nuclear envelopes form around the chrosome and centrioles to make new cells
At each pole of the cell a full set of chromosomes gather together.
A membrane forms around each set of chromosomes to create two new nuclei.
The single cell then pinches in the middle to form two separate daughter cells each containing a full set of chromosomes within a nucleus. This process is known as cytokinesis.
Significance
To provide genetic variation to ensure survival of the species and / or help a species adopt in a changing environment.
Sperm
Egg
Fuse to get 2N
Female Chromosomes
XX
Chromosomes
Male
XY
Interphase
The DNA in the cell is copied in preparation for cell division, this results in two identical full sets of chromosomes?.
Outside of the nucleus? are two centrosomes, each containing a pair of centrioles, these structures are critical for the process of cell division.
During interphase, microtubules extend from these centrosomes.
