Mitosis is the process by which the nucleus divides into two daughter nuclei each with the same number of chromosomes as the parent nucleus, maintaining genetic stability.
The nuclei formed in mitosis are genetically identical to the parent one, maintaining genetic stability.
Cells do not divide continuously, but undergo a regular cycle of division separated by periods of cell growth, known as the cell cycle.
The cell cycle consists of three stages: Interphase, Mitosis, and Cytokinesis.
Interphase occupies about 95% of the cell cycle and is a period of intense chemical activity divided into three parts: First growth (G1) phase, when the proteins from which cell organelles are synthesised are produced; Synthesis (S) phase, when DNA is replicated; Second growth (G2) phase, when organelles grow and divide and energy stores are increased.
Mitosis is the stage in the cell cycle when the nucleus divides into two.
Cytokinesis is the stage in the cell cycle when the cytoplasm of the cell divides into two.
The rate of cell division is controlled by proto-oncogenes that stimulate cell division and tumour suppressor genes that slow cell division.
The longest phase in the cell cycle of human liver cells is interphase.
Mitosis is the basis for the production of new individuals of a species by only one parent.
During mitosis, a cell divides into two daughter cells, both of which are genetically identical.
Chromatids break apart at the centromere and are pulled away by microtubules towards the poles during mitosis.
In animal cells, cytokinesis after mitosis is achieved by the growth of the cell plate at the equator from the centre outwards.
Animal cells undergoing mitosis have a centriole, but plant cells undergoing mitosis do not.
In root tip cells, cell plate formation occurs during anaphase.
The stages of mitosis are: prophase, metaphase, anaphase, telophase, and cytoplasmic cleavage.
Mitosis does not allow for the growth of multicellular organisms from unicellular zygotes.
Mitosis is used to replace identical cells and repair tissues in both plants and animals.
If a proto-oncogene becomes mutated it is called an oncogene and it stimulates cells to divide uncontrollably.
Mitosis ensures the independent assortment of homologous chromosomes.
During mitosis, the nucleolus disappears in prophase and reforms in anaphase.
If a tumour suppressor gene mutates it becomes inactive, allowing the rate of cell division to increase.
Cells that start to divide uncontrollably are often removed by the immune system; if not they may grow into tumours such as benign and malignant cancers.
The genetic information (DNA) of cells is packaged into chromosomes.
When chromosomes are visible, they appear as long, thin threads around 50μm long, made up of two strands called chromatids, joined at a point called the centromere.
The centromere is a constricted region of the chromosome containing a specific DNA sequence, to which is bound two discs of protein called kinetochores.
Centrioles organise the formation of the spindle in animal cells.
Centrioles are found only in animal cells and a pair of centrioles are found within a centrosome.
Chromosome numbers vary across species, with some protozoa having 300 chromosomes.
In animal cells, cytokinesis involves the formation of a
In animal cells, centrioles organise the formation of the spindle.
In plant cells, there is no cleavage furrow, instead vesicles derived from the Golgi apparatus move to the middle of the cell where they join together to form a cell plate.
Metaphase chromosome, Kinetochore, microtubules, Centromere, region of chromosome, Sister Chromatids, pronunciation, Kinetochore (Key - neto - chore)
In plant cells, there are no centrioles, hence no centrioles organise the formation of the spindle.
Kinetochores serve as points of attachment for microtubules that move the chromosomes during cell division.
In animal cells, cytokinesis involves the formation of a cleavage furrow which pinches the cell in two.
The cell plate enlarges until its surrounding membrane fuses with the plasma membrane along the perimeter of the cell thus forming two daughter cells.