AQA GCSE Combined Science Foundation (8464), Foundation tier · Biology › Organisation › Animal tissues, organs and organ systems
Practise Cancer. 5 exam-style questions plus unlimited generated ones on this subtopic, at up to four difficulty levels, with full mark schemes and a progress tracker. Free, no account needed.
Cancer is the result of changes in cells that lead to uncontrolled growth and division. You need to know the difference between benign and malignant tumours, how malignant tumours spread, and the lifestyle and genetic risk factors for cancer.
Key facts
Cancer = changes in cells → uncontrolled growth and division
Tumour = a mass of abnormal cells
Benign: contained in one area, usually within a membrane; does not invade other parts of the body
Malignant: cancer; invades neighbouring tissues; spreads in the blood
Secondary tumour = a new tumour formed where spreading cancer cells settle
Lifestyle risk factors: e.g. smoking, obesity, UV exposure, some viral infections
Genetic risk factors: inherited alleles, e.g. faulty BRCA alleles and breast cancer
Notes
What cancer is
Normally, cells divide by mitosis only when the body needs new cells, e.g. for growth or repair.
Cancer is the result of changes in cells that lead to uncontrolled growth and division.
A mass of abnormal cells is called a tumour.
Benign and malignant tumours
diagram
Benign tumours are growths of abnormal cells that are contained in one area, usually within a membrane. They do not invade other parts of the body. They are not cancer, but they can still cause harm by pressing on nearby organs.
Malignant tumour cells are cancers. They invade neighbouring tissues and spread to different parts of the body in the blood, where they form secondary tumours.
Benign and malignant tumours
Because they spread, malignant tumours are harder to treat and more likely to be fatal.
Risk factors for cancer
Scientists have identified lifestyle risk factors for various types of cancer, e.g. smoking (lung, mouth and throat cancers), obesity (e.g. bowel, liver and kidney cancers), too much UV light from the Sun or sunbeds (skin cancer), and infection with some viruses (e.g. HPV and cervical cancer).
Carcinogens, including ionising radiation, are also risk factors.
There are genetic risk factors for some cancers: some people inherit alleles that make certain cancers more likely, e.g. faulty BRCA alleles greatly increase the risk of breast cancer.
A risk factor increases the chance of developing cancer. It does not mean the person will definitely get it.
How to answer each type of question
Compare benign and malignant tumours
2 to 4 marksGrade 5
Make each point a comparison: 'benign ... whereas malignant ...'.
Cover: contained in one area (in a membrane) or invades neighbouring tissue; stays put or spreads in the blood; secondary tumours or not.
Example. Describe two differences between a benign tumour and a malignant tumour.
Show the model answerHide the model answer
A benign tumour is contained in one area, usually within a membrane, whereas a malignant tumour invades neighbouring tissues (1). Malignant tumour cells spread in the blood to other parts of the body and form secondary tumours, whereas benign tumour cells do not spread (1).
Don’t lose marks
Saying benign tumours are cancer. Only malignant tumour cells are cancers.
Saying cancer cells simply divide 'too fast'. The key phrase is uncontrolled growth and division.
Saying cancer spreads from person to person. Cancer is non-communicable; malignant cells spread within the body, in the blood.
Saying a risk factor 'will' cause cancer. It increases the chance.
Forgetting 'in the blood' when describing how malignant tumours spread.
More tips
Memory tricks
Benign = Bound (stays in one place, in a membrane). Malignant = Moves (invades and spreads).
Secondary tumour chain: break off → travel in the blood → settle in another organ → divide → new tumour.
Lifestyle risk factors can be changed (smoking, diet, sunbathing); genetic risk factors cannot.
Exam technique
Use the specification wording: uncontrolled growth and division; invade neighbouring tissues; secondary tumours.
In comparison questions, use 'whereas' so that each point mentions both types of tumour.
If the question mentions family members with the same cancer, think genetic risk factor; if it describes habits, name the lifestyle factor.
What each grade needs
What you need to be able to do, from the first marks up to the top grade.
Grade 3
Define cancerCancer is the result of changes in cells that lead to uncontrolled growth and division.
Grade 4
Describe a benign tumourA growth of abnormal cells contained in one area, usually within a membrane, that does not invade other parts of the body.
Grade 5
Describe malignant tumours and secondary tumoursMalignant tumour cells are cancers: they invade neighbouring tissues and spread in the blood to form secondary tumours.
Grade 5
Give lifestyle risk factors for cancerFor example smoking (lung cancer), obesity (e.g. bowel cancer), too much UV light (skin cancer) and some viral infections (e.g. cervical cancer).
Quick recall
Cover the answers and test yourself. The app has these as flashcards that come back just before you'd forget them.
Complete the sentence. Cancer is the result of changes in cells that lead to ____________ growth and division.
uncontrolled
The statements describe how a malignant tumour forms and spreads. They are not in the correct order. A Cells break off from the tumour and enter the blood. B Changes in a cell cause it to grow and divide in an uncontrolled way. C The cells are carried to another part of the body. D A tumour forms. E The cells divide to form a secondary tumour. Write the letters in the correct order.
B, D, A, C, E
Sample questions
Written for this site in the style of AQA exam questions. They are not taken from real past papers.
Question 1Easy4 marks
Cancer is a non-communicable disease.
(a) Complete the sentence. Cancer is the result of changes in cells that lead to ____________ growth and division.[1]
(b) Which statement describes a benign tumour? Tick (✓) one box.[1]
It is contained in one area, usually within a membrane.
It spreads to other parts of the body in the blood.
It forms secondary tumours.
It invades neighbouring tissues.
(c) What type of tumour invades neighbouring tissues and spreads to other parts of the body?[1]
(d) Give one lifestyle risk factor for cancer.[1]
Show the answer and mark scheme
(a)Answer: uncontrolled
uncontrolled
(b)Answer: It is contained in one area, usually within a membrane.
(c)Answer: malignant
malignant
(d)
smoking / obesity / drinking alcohol / exposure to UV (sunlight or sunbeds) / poor diet
Question 2Medium5 marks
Tumours can be benign or malignant.
(a) Give two differences between benign tumours and malignant tumours.[2]
(b) A patient has a malignant tumour in the lung. Doctors later find a secondary tumour in the brain. Explain how the secondary tumour formed.[2]
(c) Some people have a genetic risk factor for a type of cancer. What is meant by a genetic risk factor?[1]
Show the answer and mark scheme
(a)
benign tumours are contained in one area / within a membrane, malignant tumours invade neighbouring tissues
malignant tumours spread in the blood to form secondary tumours, benign tumours do not spread
(b)
cells broke off the lung tumour and were carried in the blood (to the brain)
they divided (uncontrollably) in the brain to form a new tumour
(c)
an inherited gene / allele that increases the likelihood of developing the cancer