3. Which environmental factor(s) affect skin color? A. Sunlight
b. Ultraviolet light
c. X-rays
d. All of the above

If bacteria are much too small to see, what is one reason why can we see colonies in the petri dishes that have plenty of food to eat after only a few days?

This is one of the five kingdoms in the older biological succession. organisms in this kingdom are prokaryotic.

The human body needs energy in order to carry out life processes such as breathing. where does the body get this energy? a. from eating food b. from learning about new things c. from lying in the sun d. from sleeping