Understanding Cancer and Tumour Types Revision Notes | GCSE OCR Foundation Biology

What this lesson covers

Learn what cancer is and explore the differences between benign and malignant tumours, including how they behave and spread in the body.

• Describe cancer as the result of changes in cells that lead to uncontrolled growth and division
• Compare benign and malignant tumours in terms of their characteristics and behaviour
• Explain how malignant tumour cells spread to form secondary tumours
• Evaluate the differences between localised and metastatic cancer

Key ideas to keep in view

Use this lesson to stay inside B6.3 Monitoring and maintaining health while connecting the detail back to the wider B6: Global challenges topic.

• B6: Global challenges
• B6.3 Monitoring and maintaining health
• GCSE OCR Foundation Biology

Lesson notes preview

Read the core explanations from Understanding Cancer and Tumour Types before testing yourself from memory.

• Your body contains trillions of cells, all following strict rules about when to grow and divide. But what happens when these cellular 'traffic lights' break down? The result is cancer - one of the most serious diseases affecting humans today.
• Think of normal cells like well-behaved drivers. They stop at red lights, follow speed limits, and stay in their lanes. Cancer cells are like reckless drivers who ignore all the rules, crash through barriers, and cause chaos wherever they go.
• A disease caused by changes in cells that lead to uncontrolled growth and division. These changes occur in the cell's DNA, disrupting normal cell cycle control.
• The key word here is 'uncontrolled'. Normal cells divide when your body needs them to - for growth, repair, or replacement. Cancer cells have lost this control system. They divide rapidly and continuously, forming lumps of tissue called tumours.
• Not all tumours are the same. There's a crucial difference between benign and malignant tumours - and understanding this difference could save your life. Let's examine what makes each type unique.
• A growth of abnormal cells which are contained in one area, usually within a membrane. They do not invade other parts of the body.
• Picture a benign tumour as a group of rowdy teenagers having a party in one house. They're making noise and causing problems, but they stay within the boundaries of that house. The 'house' is the membrane that surrounds the tumour, keeping it contained.
• Benign tumours grow slowly and push surrounding tissues aside rather than invading them. While they can cause problems by pressing on nearby organs, they don't spread to other parts of the body. Many can be successfully removed by surgery.
• Cancerous cells that invade neighbouring tissues and spread to different parts of the body in the blood where they form secondary tumours.
• Malignant tumours are like those same teenagers, but now they've broken out of the house and are causing trouble throughout the entire neighbourhood. They invade surrounding tissues, break into blood vessels, and travel to distant parts of the body.

Continue through the topic

Move to the related lessons or back to the topic page when you need the wider sequence before exam-style practice.