Cancer is a non-communicable disease characterised by uncontrolled cell division...
Biology346 views·Updated May 29, 2026·2 pagesUnderstanding Cancer: Causes, Tumor Types, and Risk Factors
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Tumininu@tumininu
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Understanding Cancer
Cancer develops when cells divide uncontrollably due to mutations in genes that regulate cell division. This abnormal growth forms a mass called a tumour. Unlike other diseases, cancer cannot be passed from one person to another.
Common types include breast, lung, prostate and bowel cancer, though there are many more. Not all tumours pose the same risk to your health—they fall into two important categories.
Malignant tumours are cancerous and particularly dangerous. They aren't usually encapsulated (contained within a membrane) and can break off and travel through the bloodstream to create new tumours elsewhere in the body—a process called metastasis.
Did you know? Benign tumours aren't cancerous and typically remain encapsulated, making them less dangerous than malignant ones. They don't invade other tissues and organs in the way that malignant tumours do.
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Cancer Risk Factors
Your lifestyle choices significantly influence your cancer risk. Smoking introduces tar into your body, which damages cell DNA and can trigger uncontrolled cell division in the lungs, mouth, and other organs.
Environmental factors matter too. Exposure to carcinogens like asbestos or radiation such as UV rays can penetrate skin cells and damage DNA, potentially leading to tumour development.
Your weight also plays a role. Being overweight or obese increases cancer risk, particularly for breast cancer. Fat cells release oestrogen, a hormone that can accelerate the growth of certain cancer cells.
Important to remember: Some cancer risks are inherited. The BRCA1 and BRCA2 genes help control cell division, and mutations in these genes can be passed from parents to children, significantly increasing the risk of developing certain cancers.
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Biology346 views·Updated May 29, 2026·2 pagesUnderstanding Cancer: Causes, Tumor Types, and Risk Factors
T
Tumininu@tumininu
Cancer is a non-communicable disease characterised by uncontrolled cell division that forms tumours. This condition occurs when genes controlling cell division mutate, leading to abnormal growth that can potentially spread throughout the body.
1
of 2
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Understanding Cancer
Cancer develops when cells divide uncontrollably due to mutations in genes that regulate cell division. This abnormal growth forms a mass called a tumour. Unlike other diseases, cancer cannot be passed from one person to another.
Common types include breast, lung, prostate and bowel cancer, though there are many more. Not all tumours pose the same risk to your health—they fall into two important categories.
Malignant tumours are cancerous and particularly dangerous. They aren't usually encapsulated (contained within a membrane) and can break off and travel through the bloodstream to create new tumours elsewhere in the body—a process called metastasis.
Did you know? Benign tumours aren't cancerous and typically remain encapsulated, making them less dangerous than malignant ones. They don't invade other tissues and organs in the way that malignant tumours do.
2
of 2Sign up to see the content. It's free!
- Access to all documents
- Improve your grades
- Join milions of students
Cancer Risk Factors
Your lifestyle choices significantly influence your cancer risk. Smoking introduces tar into your body, which damages cell DNA and can trigger uncontrolled cell division in the lungs, mouth, and other organs.
Environmental factors matter too. Exposure to carcinogens like asbestos or radiation such as UV rays can penetrate skin cells and damage DNA, potentially leading to tumour development.
Your weight also plays a role. Being overweight or obese increases cancer risk, particularly for breast cancer. Fat cells release oestrogen, a hormone that can accelerate the growth of certain cancer cells.
Important to remember: Some cancer risks are inherited. The BRCA1 and BRCA2 genes help control cell division, and mutations in these genes can be passed from parents to children, significantly increasing the risk of developing certain cancers.
We thought you’d never ask...
What is the Knowunity AI companion?
Our AI Companion is a student-focused AI tool that offers more than just answers. Built on millions of Knowunity resources, it provides relevant information, personalised study plans, quizzes, and content directly in the chat, adapting to your individual learning journey.
Where can I download the Knowunity app?
You can download the app from Google Play Store and Apple App Store.
Is Knowunity really free of charge?
That's right! Enjoy free access to study content, connect with fellow students, and get instant help – all at your fingertips.
Most popular content: Cancer
3Most popular content in Biology
9Most popular content
9Can't find what you're looking for? Explore other subjects.
Students love us — and so will you.
4.6/5App Store
4.7/5Google Play
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan SiOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha KlichAndroid user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
AnnaiOS user