Question

Electromagnetic waves used in medicine to destroy cancer cells (A) radio waves (B) infrared rays (C) gamma rays (D) ultraviolet rays

Short answer

The correct answer is (C) gamma rays. Gamma rays have high frequencies and very short wavelengths, allowing them to penetrate deep into the body and effectively kill cancer cells without damaging the surrounding tissues.

Step-by-step solution

Understanding the Electromagnetic Spectrum

The electromagnetic spectrum is the range of all possible frequencies of electromagnetic radiation. It is divided into several sections, including radio waves, microwaves, infrared rays, visible light, ultraviolet rays, X-rays, and gamma rays. Each section has unique properties and uses in various fields.

Analyzing the Options

Now let's analyze the given options and their applications in medicine: (A) Radio waves have low frequencies and long wavelengths. They are mostly used in communication systems and are not used to destroy cancer cells. (B) Infrared rays have slightly higher frequencies and shorter wavelengths than radio waves. These rays are used in heat therapy and for taking thermal images, but they do not destroy cancer cells. (C) Gamma rays have high frequencies and very short wavelengths. These rays have high energy and can penetrate deep into the body. In medicine, their high-energy nature allows them to kill cancer cells without damaging the surrounding tissues. (D) Ultraviolet rays have frequencies between visible light and X-rays. These rays are used for sterilization and disinfection, but they are not used to destroy cancer cells.

Choosing the Correct Answer

Based on our analysis, we can conclude that (C) gamma rays are the type of electromagnetic waves used in medicine to destroy cancer cells. The high-energy nature of gamma rays enables them to target and kill cancer cells effectively without causing significant damage to surrounding tissues.

Key concepts

Gamma Rays

Gamma rays are the most energetic form of electromagnetic radiation and occupy the far end of the electromagnetic spectrum.
They have the highest frequencies and the shortest wavelengths, which makes them unique among electromagnetic waves.
The high energy of gamma rays allows them to penetrate substances that other types of radiation cannot easily pass through. This penetrating power is one of the reasons why gamma rays are so valuable in medical applications. Unlike visible light, which can be blocked by a mere piece of paper, gamma rays can pass through significant layers of materials, including human tissue. Gamma rays are naturally emitted by radioactive atoms and in some cosmic events like supernovae. However, in medical applications, gamma rays are often produced using machines such as linear accelerators. These devices can generate a controlled and concentrated beam of gamma rays that can be directed precisely at their target.

Cancer Treatment

In the realm of cancer treatment, gamma rays play a crucial and life-saving role. Their ability to kill cancer cells while preserving surrounding healthy tissues makes them a cornerstone of radiation therapy.
Known as radiotherapy, this treatment exploits the properties of gamma rays to combat malignant tumors. Gamma rays can induce changes in the DNA of cells, which can effectively lead to the death of cancerous cells.

• Radiation therapy targets precise areas of cancerous growth, using beams angled to focus on the tumor.
• Healthy tissues are largely spared since gamma rays can minimize damage thanks to their targeted delivery.
• Different techniques, including external beam radiation and brachytherapy, utilize gamma rays for various depths and types of cancer.

The precision involved in targeting cancerous tissues reduces the side effects typically associated with cancer treatment. This has revolutionized the therapeutic approach to treating cancers otherwise considered inoperable due to their location or size.

Medical Applications of Electromagnetic Waves

Electromagnetic waves cover a broad spectrum and are employed widely across different medical applications beyond just cancer treatment.
Each type of wave, owing to its unique properties, serves specific functions:

• Radio Waves: Primarily used in MRI machines to generate detailed internal images of the body without using harmful radiation.
• Infrared Rays: Used in thermal imaging to detect heated areas of the body, helpful in both diagnostic and therapeutic settings.
• Ultraviolet Rays: Applied for sterilizing medical equipment and treating certain skin conditions, supporting hygiene in medical environments.
• X-rays: Utilized in medical imaging to reveal the internal structure of the body, especially bones and certain tissues.

While each form of electromagnetic wave offers distinct medical benefits, it is the specific properties like wavelength and frequency that determine its suitability for a particular application. This diversity allows electromagnetic waves to aid in diagnosis, treatment, and research, illustrating their versatile role in advancing healthcare.