Physical Principles in Living Systems (Physical Science)

6. Physical principles underlie biological structures and functions. As a basis for understanding this concept:

a. Students know visible light is a small band within a very broad electromagnetic spectrum.

b. Students know that for an object to be seen, light emitted by or scattered from it must be detected by the eye.

c. Students know light travels in straight lines if the medium it travels through does not change.

d. Students know how simple lenses are used in a magnifying glass, the eye, a camera, a telescope, and a microscope.

e. Students know that white light is a mixture of many wavelengths (colors) and that retinal cells react differently to different wavelengths.

f. Students know light can be reflected, refracted, transmitted, and absorbed by matter.

g. Students know the angle of reflection of a light beam is equal to the angle of incidence.

h. Students know how to compare joints in the body (wrist, shoulder, thigh) with structures used in machines and simple devices (hinge, ball-and-socket, and sliding joints).

i. Students know how levers confer mechanical advantage and how the application of this principle applies to the musculoskeletal system.

j. Students know that contractions of the heart generate blood pressure and that heart valves prevent backflow of blood in the circulatory system.