In the Medical Diagnostic Technique Known as Positron Emission Tomography $\gamma$

question 37

Multiple Choice

In the medical diagnostic technique known as positron emission tomography (PET) , a positron and an electron annihilate each other and two $\gamma$ -ray photons are emitted. What is the angle between the momentum vectors of the two photons?

• A)zero degrees
• B)45°
• C)90°
• D)180°
• E)Any angle is possible.

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Definitions:

Cerebrum

The largest part of the brain, responsible for voluntary muscular activity, vision, speech, taste, hearing, thought, and memory.

Limbic System

A complex system of nerves and networks in the brain, involved in basic emotions and drives.

Hypothalamus

A region of the brain responsible for hormone production and regulation of vital bodily functions such as temperature and hunger.

Pons

A part of the brain located in the brainstem, vital for regulating breathing, communication between different parts of the brain, and relaying sensory information.