Definitions [6]
Definition: Drug abuse
Drug abuse is the improper or excessive use of drugs that leads to harmful effects on physical, mental and social health.
Definition: Cancer
Cancer is a disease characterised by uncontrolled and abnormal division of body cells due to loss of normal growth regulation.
Definition: Metastasis
Metastasis is the process by which cancer cells spread from the primary site to distant organs via the bloodstream or lymphatic system.
Definition: Tumour
A tumour is a mass of abnormally proliferating cells formed due to uncontrolled cell division.
Definition: Malignant tumour
A malignant tumour is a cancerous tumour that grows rapidly, invades surrounding tissues and spreads to distant organs.
Definition: Benign tumour
A benign tumour is a non-cancerous tumour that remains confined to its original site and does not spread to other parts of the body.
Key Points
Key Points: Drug Abuse
- Drug abuse is the excessive use of harmful substances, often starting in teenagers due to academic stress, peer pressure, or curiosity.
- Commonly abused substances include opioids, cannabinoids, and prescription medicines, which are also sometimes illegally used by athletes to boost performance.
- Severe health effects of long-term drug use include dangerous organ damage, nervous system failure, coma, and even sudden death.
- Major warning signs of addiction in students include a sudden drop in academic performance, unusual aggression, and severe social isolation.
- Effective prevention involves avoiding negative peer pressure, maintaining open communication with parents, and seeking professional medical help if needed.
Key Points: Cancer
- Meaning: Cancer is the abnormal, uncontrolled division of cells forming a mass called a neoplasm/tumour. Cancer cells lack contact inhibition and compete with normal cells for nutrients.
- Benign Tumour: Grows slowly, stays restricted to its site of origin (localised), and does not spread. It can still be harmful (e.g., a brain tumour). Examples: adenoma and fibroid.
- Malignant Tumour: Grows rapidly, invades surrounding tissues, and spreads to other organs via the bloodstream or lymphatic system, forming secondary tumours. This spreading process is called metastasis.
- Types of Cancer: Based on tissue affected – Carcinoma, Sarcoma, Lymphoma, Leukaemia, and Adenocarcinoma.
