3.1 understanding principles of cancer Flashcards
what is cancer?
- abnormal cell division
- alteration of cell cycle
what are the 3 stages of the cell cycle
- interphase- (3 phases- gap 1, synthesis, gap 2)
- mitosis (cell divides- 3 stages)
- G0 stationary phase (cells in G0 have specialised- no further changes occur)
what are the stopping cells
control of the cell cycle
- proteins
- genes code for proteins
what do stopping proteins do
control of the cell cycle
- either breakdown or ar modified by cellular processes to allow the cycle to continue
- regulates the speed at which cells can divide
- can stop cell division from ever occuring
what are DNA repair genes
control of the cell cycle
- genes that check and repair DNA when it is being synthesised (replication)
- they stop mutations from occuring- avoiding cancer
results of mutations
- abnormal cell division
- alteration of cell cycle
- uncontrolled proliferation of cells
what is Apoptosis?
- programmed cell death
- cells with damaged DNA are potential sources of cancer
- old, altered cells with unfixable DNA are targeted by the body for destruction
- breaks down cells into their component molecules
proto oncogenes
cancerous cells that have acquired a series of mutations
why is abnormal cell division a multi-step process
where multiple mechanisms must fail before a cell becomes cancerous.
list the proto ocogenes of cancerous cells
- make them divide more quickly
- allows them to escape controls on cell division
- damages the DNA repair mechanisms
- allows them to avoid programmed cell death
primary cancer
where the cancer starts
secondary cancer
- when cancer cells break away from primary cancer via bloodstream and lymph
- a new cancer growth
- still the same cell type as primary cancer
differences between cancer cells and normal cells
- normal cells: controlled growth, specialised cells, even appearance, even shaped nuclei, organised arrangement
- cancer cells: contact inhibition, undifferentitated, variable appearance and shape, disporganised arrangement.
features of cancer cells
- grow and divide at an abnormally rapid rate
- are poorly differentiated
- have abnormalites in their: membranes, cytoskeletal proteins, morphology
types of cancerous tumours
- Carcinoma;
- Sarcoma;
- Leukaemia;
- Lymphoma;
- Melanoma.
benign tumour
Non-invasive tumours; not considered to be cancer.
carcinoma cancer
type of cancer that starts in cells that make up the skin or tissie lining the organs. e.g. liver or kidney
sarcoma cancer
rare cancers that develop in the muscle, bone, nerves, cartilage, tendons, blood vessels and the fatty and fibrous tissues.
leukaemia
is any type of cancer that affects the blood and bone marrow where blood cells are made e.g. Acute myeloid leukaemia
lymphoma
any type of blood cancer that develops from lymphocytes (a type of white blood cell). E.g Non Hodgkin and Hodgkin lymphomas
melanoma
any type of cancer that develops from the pigment-containing cells known as melanocytes. Melanomas typically occur in the skin, but may rarely occur in the mouth, intestines, or eye. E.g. ocular melanoma
malignant tumour
An invasive tumour that can spread around the body; true cancer
