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Cancer and cardiovascular disease - Non-communicable - OCR GatewayCancer and carcinogens

The chance of developing a non-communicable disease can be increased or decreased depending upon a person鈥檚 lifestyle or the genes they inherit. Two common types are cancer & cardiovascular disease.

Part of Biology (Single Science)Global challenges

Cancer and carcinogens

Cancer

When a person is growing or replacing old and damaged cells, new cells are produced by .

Sometimes, cells begin to divide uncontrollably. New cells are produced 鈥 even if the body does not need them. This produces a growth called a .

Types of tumour

There are two types of tumour 鈥 and :

Type of tumourCharacteristics
BenignNormally grow slowly
BenignUsually grow within a membrane, so can easily be removed and in most cases do not grow back
BenignDo not spread to other parts of the body
BenignCan still be life-threatening if they cause damage to an organ
MalignantAre cancerous
MalignantNormally grow quickly
MalignantCan spread to other parts of the body in the bloodstream
MalignantAs the tumour grows, cancer cells detach and can form secondary tumours in other parts of the body - this is called metastasis
Type of tumourBenign
CharacteristicsNormally grow slowly
Type of tumourBenign
CharacteristicsUsually grow within a membrane, so can easily be removed and in most cases do not grow back
Type of tumourBenign
CharacteristicsDo not spread to other parts of the body
Type of tumourBenign
CharacteristicsCan still be life-threatening if they cause damage to an organ
Type of tumourMalignant
CharacteristicsAre cancerous
Type of tumourMalignant
CharacteristicsNormally grow quickly
Type of tumourMalignant
CharacteristicsCan spread to other parts of the body in the bloodstream
Type of tumourMalignant
CharacteristicsAs the tumour grows, cancer cells detach and can form secondary tumours in other parts of the body - this is called metastasis

The diagrams shows how cancer cells can invade surrounding tissue:

This shows how cancer cells can invade surrounding tissue.
Image shows how malignant cells can divide and invade normal cells.
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  1. Diagram of how the tumour secretes chemicals

    Development of a tumour

What causes cancer?

Something that increases the likelihood of developing a disease is called a . Chemicals and other agents that can cause cancer are called .

Carcinogens cause cancer by damaging . Carcinogens increase the chance that will occur. A single mutation will not usually cause cancer 鈥 several are required. For this reason, we are more likely to develop cancer as we get older. There are several risk factors for various types of cancers.

Genetic factors

There are genetic risk factors that increase the likelihood of developing some cancers. For example, inheriting a mutation in the BRCA1 gene can increase a person's risk of developing breast cancer.

Lifestyle factors

  • Viruses linked with cancer, such as the human papilloma virus (HPV), being spread from person to person through sexual intercourse.
  • The chemical carcinogens in cigarette smoke increasing the risk of lung cancer.
  • Alcohol intake is linked with certain cancers, such as liver cancer.
  • Exposure to , part of which is , during sunbathing or outdoor activities, leading to the development of skin cancers.
  • Diet, including fat and salt intake, increases the risk of cancer.

Industrial and environmental factors

  • Exposure to ionising radiation such as UV radiation from sunlight.
  • Exposure to chemical carcinogens. An example is asbestos.
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Development of cardiovascular disease

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