Which characteristic is necessary for natural

selection to occur in a species?

(1) stability

(2) variation

(3) complex cellular organization

(4) a very low mutation rate

If jennifer wants to reduce the risk of having a baby with a birth defect caused by an environmental substance like drugs or alcohol, she should try her best to avoid these substances during

What is a closed curculatory system

A large white and gray log that smells like pine is burned in a fire pit. After being completely burned, all that remains of the log is a small pile of soft white-gray ashes that no longer smell of pine.

What is a limiting amino acid in a dietary protein?

How is the Sun classified? as a giant star as a medium star as a white dwarf as a neutron star

What type of learning describes when animals learn by watching or listening to others of their species?

The process of grouping things based on their similarities is?

Why do you think more blood goes to some organs and not others?

Which of the following would most likely employ a forester? A. a state governments B. lumber businesses C. national govemments D. all of the above

How do environmental scientists use technology to track polar bears?