Biology - Cell division and cancer keywords

the process of producing two identical copies of DNA from one original DNA molecule

the series of events that take place in a cell during the period between one cell division and the next

the name given to chromosomes when they are not dividing

DNA polyamerase

one of the two identical strands formed after DNA replication

the point at which two chromatids are held together

contains one set of chromosomes ie. it only has one of each type of chromosome in the nucleus

has two sets of chromosomes ie. it has two of each type of chromosome in the nucleus

a form of nuclear division in which one or more nucleus divides to form two nuclei, each containing the same number of chromosomes with identical genes

a form of nuclear division in which the four daughter nuclei contain half the chromosome number of the parent nucleus

- asexual reproduction in unicellular organisms
- growth and repair in multicelular organisms

- sexual reproduction involving gametes (while maintaining parents chromosome number)
- allows for variation due to the formation of new sets of genes

a group of disorders in which certain cells loose their ability to control the rate of mitosis and the number of times mitosis takes place

- specialised to carry out a specific role
- self destruct if they become damaged or too old
- attach to each other in the right places in the body
- reproduse when and where necessary but mitosis stops when necessary

- dont stop growing and dividing by mitosis
- ignore signals from other cells
- dont stick together
- dont specialise
- dont repair themselves or die
- look different and have different chemical markers on their surfaces

the cells stop dividing after some time, theyre not life threatening and dont invade other tissues. benign tumours can be surgically removed

dont stop growing, are cancerous. they may be life threatening and they invade other cells and move from one place to another, they continue to divide indefinitely

the movement of malignant cells

- smoking
- excessive UV exposure
- inhaling asbestos fibres
- contact with pesticides
- inhaling exhaust fumes
- exposure to radon gas

- age
- family history
- reduced immunity due to infection or drugs
- high stress levels
- inflamation
- exosure to carscinogens

- smoking
- being overweight
- poor diet
- lack of excersise
- too much alcohol
- over exposure to sunlight

diagnosing cancer while the tumor is not large and hasnt spread means treatment is more likely to be succesful. eg of vhanges
- lump or swelling
- abnormal bleeding
- unexplained weight loss

chemicals or drugs used to slow or stop the process of cancer cells growing, reduce their size or kill any cancer cells that are alive after sugery. the drugs are said to be cytotoxic drugs as they kill fast growing cells and often have side effects

uses high energy rays to kill the cancer cells

a treatment in which the immune system is boosted and used to fight off cancer

a vaccine is a non disease causing dose of a disease causing organism that stimulates the production of antibodies against the disease causing organism

the phase in the life cycle of a cell when its not dividing

the dividing of the cytoplasm to form two seperate cells immediately after mitosis

chromosomes contract and become visible in the nucleus as short thickend strands
each chromosome appears as a double strand
spindle fibres begin to apear at the cytoplasm of the cell
the nuclear membrane starts to break down

nuclear membrane is fully broken down
two spindle fibres from each end of the cell attach to each chromosome
chromosomes move so they line up across the equator of the cell

spindle fibres contract causing the two strands of each chromosome to seperate
the two strands are pulled to opposite ends of the cell
each chromosome has identical genes

nuclear membrane forms around each of the two sets of chromosomes
the chromosomes elongate within the nucleus and become hard to distinguish
spindle fibres break down