Mitosis 2.6.2 Flashcards
What is mitosis?
The division of a cell which results in two diploid identical daughter cells being produced.
Name 3 organisms that divide by mitosis
- Fungi (yeast)
- Some plants; strawberry
- Single celled protoctists - amoeba
State the chain of growth in organisms
Cell - cells - tissues - organs - organ systems - organism
How does mitosis aid organisms?
Through growth and repair.
How does the process of mitosis work in the repair of organisms?
Wounds heal when growth factors, secreted by platelets and macrophages (white blood cells) and damaged cells of the blood-vessel walls, stimulate the proliferation of endothelial cell and smooth muscle cells to repair damaged blood vessels.
What is the sequence of mitosis?
Prophase -> metaphase -> anaphase -> telophase
State the structure of a chromosome
- Consist of two chromatids joined somewhere along its length at the centromere
- Genetic information (genes/alleles) carried on each chromatid is identical.
State what happens during interphase in animal cells
Cell growth occurs and DNA replication happens, also centrioles replicate (animal cells only)
The chromosomes present as granular material (chromatin)
What happens during prophase in mitosis?
Chromosomes condense, the nuclear envelope breaks down and spindle fibres begin to form in the regions of the centrioles
What happens during metaphase in mitosis?
Chromosomes align at the equator of the cell, and spindle fibres are attached via the centromeres
What happens during anaphase in mitosis?
The sister chromatids of each chromosome are separated as the cell enters anaphase, and they move to opposite poles of the cell.
What happens during telophase in mitosis?
The chromosomes begin to uncoil and a nuclear membrane begins to form around each set of chromosomes - the spindle fibres begin to disintegrate.
What happens during cytokinesis?
Division of the cytoplasm, forming two genetically identical daughter cells.
What happens during cytokinesis in plant cells?
Constriction of the membrane cannot occur due to the cell wall being present, therefore a cell membrane forms in the middle of the dividing cell and this membrane secretes cell wall material onto each side.
