Medical Physics: Radiation Therapy, Diagnostic Imaging, and Radiation Protection

Question 1

During radiation therapy, ionizing radiation damages cancer cells primarily by causing:

Accepted Answer

DNA strand breaks

Answer

Protein denaturation

Answer

Cell membrane damage

Answer

Mitochondrial dysfunction

Question 2

Which imaging technique uses magnetic fields and radio waves to produce detailed cross-sectional images of the body?

Accepted Answer

Magnetic resonance imaging (MRI)

Answer

X-ray imaging

Answer

Computed tomography (CT)

Answer

Ultrasound imaging

Question 3

Which of the following is not a key principle of radiation protection?

Accepted Answer

Exposure

Answer

Time

Answer

Distance

Answer

Shielding

Question 4

In computed tomography (CT) scanners, the primary type of radiation used is:

Accepted Answer

X-rays

Answer

Alpha particles

Answer

Beta particles

Answer

Gamma rays

Question 5

Ionizing radiation is characterized by its ability to:

Accepted Answer

Remove tightly bound electrons from atoms

Answer

Penetrate deep into matter

Answer

Be non-carcinogenic

Answer

Be used in conventional X-ray imaging

Question 6

The primary purpose of a collimator in radiation therapy is to:

Accepted Answer

Shape the beam of radiation

Answer

Increase the energy of the beam

Answer

Protect healthy tissues from radiation

Answer

Measure the dose of radiation delivered

Question 7

In the UK, the recommended maximum dose of ionizing radiation that a member of the public can receive in a year is:

Accepted Answer

10 mSv

Answer

1 mSv

Answer

100 mSv

Answer

1 Sv

Question 8

Ultrasound is an example of a:

Accepted Answer

Non-ionizing radiation source

Answer

Ionizing radiation source

Answer

Particle accelerator

Answer

Radioactive isotope

Question 9

The primary function of a radiation dosimeter is to:

Accepted Answer

Measure the dose of radiation a person has been exposed to

Answer

Generate radiation for medical purposes

Answer

Protect against radiation exposure

Answer

Calibrate radiation therapy equipment

Question 10

What is the main role of medical physicists in healthcare?

Accepted Answer

Providing technical support for medical imaging equipment

Answer

Prescribing radiation therapy

Answer

Interpreting medical images

Answer

Developing new medical imaging technologies

Question 11

How does ionizing radiation primarily damage the DNA of living cells?

Accepted Answer

By exciting electrons and breaking chemical bonds within the DNA molecule

Answer

By increasing the temperature of the DNA, causing it to denature

Answer

By directly altering the genetic code of the DNA

Question 12

Which type of radiation, commonly used in medical imaging, has the ability to ionize atoms and molecules?

Accepted Answer

X-rays

Answer

Ultrasound

Answer

Magnetic resonance imaging

Answer

Computed tomography

Question 13

In radiation therapy, the absorbed dose is measured in:

Accepted Answer

Gray (Gy)

Answer

Sievert (Sv)

Answer

Rad

Answer

Becquerel (Bq)

Question 14

When X-rays interact with biological tissues, which fundamental process plays a dominant role?

Accepted Answer

Photoelectric effect

Answer

Compton scattering

Answer

Pair production

Answer

Cherenkov radiation

Question 15

In magnetic resonance imaging (MRI), contrast agents are utilized to improve the visibility of specific structures. Which type of contrast agent is commonly employed for this purpose?

Accepted Answer

Gadolinium contrast agents

Answer

X-ray tubes

Answer

Ultrasound waves

Answer

Computed tomography

Question 16

In nuclear medicine imaging, a collimator is used primarily for:

Accepted Answer

Focusing the radiation beam

Answer

Detecting radiation

Answer

Shielding the patient from radiation

Answer

Producing radioisotopes

Question 17

Which type of radioactive decay involves the emission of a positively charged particle?

Accepted Answer

Alpha decay

Answer

Beta decay

Answer

Gamma decay

Answer

Electron capture

Question 18

The SI unit for measuring the intensity of radioactive decay is:

Accepted Answer

Becquerel (Bq)

Answer

Curie (Ci)

Answer

Gray (Gy)

Answer

Sievert (Sv)

Question 19

In radiation therapy, the treatment plan serves the primary purpose of:

Accepted Answer

Determining the optimal dose and beam configuration

Answer

Monitoring patient response to treatment

Answer

Calculating the cost of treatment

Answer

Scheduling patient appointments

Question 20

Which type of radiation, commonly used in medical applications, is classified as ionizing?

Accepted Answer

Gamma rays

Answer

Visible light

Answer

Ultrasound waves

Answer

Microwaves

Question 21

What is the primary goal of implementing radiation protection measures?

Accepted Answer

Minimize the negative effects of radiation exposure

Answer

Completely eliminate all radiation exposure

Answer

Monitor radiation levels in the environment

Answer

Treat radiation-induced injuries

Question 22

In medical imaging, why is the half-life of a radioactive isotope significant?

Accepted Answer

Affects the dosage of the radioisotope administered

Answer

Determines the duration of the imaging procedure

Answer

Influences the resolution of the resulting images

Answer

Has no impact on medical imaging applications

Question 23

Which organ is most vulnerable to damage caused by radiation?

Accepted Answer

Bone marrow

Answer

Skin

Answer

Lungs

Answer

Liver

Question 24

In medical imaging, what is the purpose of using contrast agents?

Accepted Answer

Enhance the visibility of specific structures

Answer

Reduce radiation exposure

Answer

Improve image resolution

Answer

Prevent motion artifacts

Question 25

In healthcare, what is the primary responsibility of a medical physicist?

Accepted Answer

Ensuring the safe and effective use of radiation

Answer

Optimizing medical imaging procedures

Answer

Developing new medical imaging technologies

Answer

Treating patients with radiation therapy

Question 26

Which imaging technique is BEST suited for each medical application?

Accepted Answer

X-rays: Bones; MRI: Soft tissues; CT scans: Detailed cross-sections

Answer

X-rays: Detailed cross-sections; MRI: Soft tissues; CT scans: Blood flow

Answer

MRI: Bones; CT scans: Blood flow; X-rays: Soft tissues

Answer

CT scans: Soft tissues; MRI: Blood flow; X-rays: Bones

Question 27

In the history of radiation therapy, what was the key contribution of cobalt-60?

Accepted Answer

It allowed for more precise and effective radiation delivery to cancerous tumors.

Answer

It was the first radioactive substance used in radiation therapy.

Answer

It led to the development of modern imaging techniques like CT scans.

Answer

It replaced X-rays in radiation therapy.

Question 28

Which of the following types of radiation are commonly used in radiation therapy?

Accepted Answer

Gamma radiation and X-rays

Answer

Alpha radiation

Answer

Beta radiation

Question 29

What is the primary purpose of using a radiation dosimeter?

Accepted Answer

To measure the amount of radiation exposure received

Answer

To detect the presence of radioactive substances

Answer

To determine the effectiveness of radiation therapy

Answer

To protect individuals from excessive radiation

Question 30

What is the underlying principle behind the use of radiation in cancer treatment?

Accepted Answer

Radiation selectively targets and damages cancer cells

Answer

Radiation reduces blood flow to tumors

Answer

Radiation stimulates the immune system to fight cancer

Answer

Radiation replaces damaged cells with healthy ones

Question 31

Which of the following is NOT a form of radioactive decay?

Accepted Answer

Neutron decay

Answer

Alpha decay

Answer

Beta decay

Answer

Gamma decay

Question 32

What is the key responsibility of a medical physicist in healthcare?

Accepted Answer

To ensure the safe and effective use of radiation in medical applications

Answer

To develop new medical imaging techniques

Answer

To diagnose and treat radiation-related illnesses

Answer

To provide radiation protection guidance

Question 33

Which of the following is NOT a property of ionizing radiation?

Accepted Answer

It does not cause DNA damage

Answer

It can penetrate matter

Answer

It can ionize atoms and molecules

Answer

It can be used for medical imaging and therapy

Question 34

What is the function of a collimator in a CT scanner?

Accepted Answer

To reduce scatter radiation and improve image quality

Answer

To focus the X-ray beam onto a specific area

Answer

To shield the patient from excessive radiation

Answer

To increase the radiation dose to the patient

Question 35

Which of the following is a type of radiation therapy that involves the use of radioactive seeds or pellets?

Accepted Answer

Brachytherapy

Answer

External beam radiation therapy

Answer

Proton therapy

Answer

Cryosurgery

Question 36

What is the primary responsibility of a medical physicist in radiation protection?

Accepted Answer

To develop and implement radiation safety protocols and guidelines

Answer

To conduct radiation therapy treatments

Answer

To research new radiation technologies

Answer

To operate radiation equipment

Question 37

Which of the following is a characteristic of non-ionizing radiation?

Accepted Answer

It does not have enough energy to ionize atoms or molecules

Answer

It is used in medical imaging

Answer

It can cause skin burns

Answer

It can penetrate matter easily

Question 38

What is the purpose of using a radiation survey meter?

Accepted Answer

To detect and measure levels of radiation in an environment

Answer

To determine the radiation dose received by an individual

Answer

To calibrate radiation equipment

Answer

To treat radiation-related injuries

Question 39

Which type of radiation is **not** used in medical imaging?

Accepted Answer

Alpha radiation

Answer

Ultrasound

Answer

X-rays

Answer

Gamma rays

Question 40

What is the primary goal of radiation therapy?

Accepted Answer

To destroy cancerous cells while minimizing damage to healthy tissue.

Answer

To relieve pain associated with the tumor.

Answer

To prevent the spread of cancer cells.

Question 41

Which imaging technique utilizes sound waves to create images?

Accepted Answer

Ultrasound

Answer

MRI

Answer

X-ray

Question 42

What is the primary purpose of a lead apron during medical imaging procedures?

Accepted Answer

To protect the patient and staff from radiation exposure.

Answer

To improve image quality.

Answer

To reduce the time required for the procedure.

Question 43

During a CT scan, cross-sectional images of the body are obtained using:

Accepted Answer

X-rays

Answer

Magnetic fields

Answer

Sound waves

Question 44

What is a key advantage of MRI over other imaging techniques?

Accepted Answer

MRI can provide better visualization of soft tissues.

Answer

MRI is less expensive than other methods.

Answer

MRI is less invasive than other methods.

Answer

MRI does not require the use of radiation.

Question 45

Which statement about the role of medical physicists is accurate?

Accepted Answer

Medical physicists ensure the accuracy and safety of medical imaging equipment.

Answer

Medical physicists provide medical care to patients.

Answer

Medical physicists design and build medical imaging equipment.

Question 46

Which factor can influence the effectiveness of radiation therapy?

Accepted Answer

The size and location of the tumor

Answer

The patient's gender

Answer

The patient's occupation

Answer

The patient's social status

Question 47

What is the main purpose of radioactive tracers in medical imaging?

Accepted Answer

To visualize specific organs or tissues.

Answer

To enhance the quality of images.

Answer

To diagnose specific diseases.

Answer

To reduce the amount of radiation exposure.