Nitrogen in the atmosphere must be "fixed" before it can be used by plants. Atmospheric nitrogen is "fixed" by

How could you determine if a specimen was a living organism

Describe why a and b blood types are considered to be codominant.

How is relative age different from the absolute age of a geologic or evolutionary event

The first true cells were most likely - a. aerobic. c. eukaryotic. b. anaerobic. d. archaebacteria.

Use the Punnet Squares interactive, Level 3 to conduct a cross between a man with normal vision and a woman with the gene for color blindness. A man with normal vision, XB Y, and a woman who is a carrier for color blindness, XB Xb, mate.

Which organ is a part of circulatory system? select one of the options below as your answer: a. brain b. heart c. lungs d. stomach?

Although they do not have recent common ancestors, birds and bats have similar body shapes necessary for powered flight. what pattern of evolution does this relationship represent?

The science of naming organism and putting them into classification group is?

What kind of energy does the TV have

What can stimulate cell regulators to increase cell reproduction? fragmentation hormones isogametes elongation