Guidelines: Answer the following critical thinking questions and others that may come to mind to focus students' attention on the lesson content. Each response must be a minimum of 100 words. All responses must be typed.

1. During beam attenuation, what occurs at the molecular level of anatomic tissues to affect the quantity and quality of the radiation exiting the patient?

2. How does the composition of varying types of matter affect the electromagnetic radiations throughout the spectrum?

3. How different do you think medicine would be today without medical imaging? Why do we need units of measure in our daily lives?

4. Clearly differentiate between photoelectric and Compton interactions and how they relate to absorption and scattering.