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Read the following statements carefully....

Read the following statements carefully.
(i) Cancer causing viruses have genes called viral oncogenes.
(ii) Malignant tumors remain confined to their original location.
(iii) Cancer cells do not exhibit contact inhibition.
(iv) X-rays and UV rays are not potent carcinogens.
(v) Cancer detection is based on biopsy.
Which of the above statements are not correct regarding cancer ?

A

(iii) and (v)

B

(ii) and (iv)

C

(i), (iii) and (v)

D

(ii), (iv) and (v)

Text Solution

AI Generated Solution

The correct Answer is:
To determine which statements about cancer are not correct, we will analyze each statement one by one: 1. **Statement (i):** "Cancer causing viruses have genes called viral oncogenes." - **Analysis:** This statement is correct. Certain viruses that cause cancer indeed have genes known as viral oncogenes. These genes can induce cancer by promoting uncontrolled cell division. Examples include the Epstein-Barr virus, human papillomavirus, and hepatitis B virus. 2. **Statement (ii):** "Malignant tumors remain confined to their original location." - **Analysis:** This statement is incorrect. Malignant tumors do not remain confined; they have the ability to invade surrounding tissues and spread to other parts of the body through a process known as metastasis. In contrast, benign tumors remain localized. 3. **Statement (iii):** "Cancer cells do not exhibit contact inhibition." - **Analysis:** This statement is correct. Normal cells exhibit contact inhibition, meaning they stop dividing when they come into contact with other cells. Cancer cells lose this ability and continue to grow uncontrollably, leading to tumor formation. 4. **Statement (iv):** "X-rays and UV rays are not potent carcinogens." - **Analysis:** This statement is incorrect. Both X-rays and UV rays are known to be potent carcinogens. Prolonged exposure to these forms of radiation can lead to DNA damage and increase the risk of cancer. 5. **Statement (v):** "Cancer detection is based on biopsy." - **Analysis:** This statement is correct. A biopsy involves taking a sample of tissue suspected of being cancerous and examining it microscopically for abnormal cell growth. This is a standard method for diagnosing cancer. **Conclusion:** The statements that are not correct regarding cancer are: - **Statement (ii)**: Malignant tumors remain confined to their original location. (Incorrect) - **Statement (iv)**: X-rays and UV rays are not potent carcinogens. (Incorrect) ### Final Answer: The statements that are not correct are (ii) and (iv).
To determine which statements about cancer are not correct, we will analyze each statement one by one: 1. **Statement (i):** "Cancer causing viruses have genes called viral oncogenes." - **Analysis:** This statement is correct. Certain viruses that cause cancer indeed have genes known as viral oncogenes. These genes can induce cancer by promoting uncontrolled cell division. Examples include the Epstein-Barr virus, human papillomavirus, and hepatitis B virus. 2. **Statement (ii):** "Malignant tumors remain confined to their original location." - **Analysis:** This statement is incorrect. Malignant tumors do not remain confined; they have the ability to invade surrounding tissues and spread to other parts of the body through a process known as metastasis. In contrast, benign tumors remain localized. ...
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