Nitrogen in the atmosphere must be "fixed" before it can be used by plants. Atmospheric nitrogen is "fixed" by A) plants. B) bacteria. C) bacteria and insects. D) bacteria and lightning.

Wind erosion___. A. removes the fertile B horizon of soil B. can be reduced my cutting down trees C. happens slowly in dry climates D. is both constructive and destructive

Which of the following accurately describes the patterns of inheritance in human blood types?

How did Galileo's father influence his interest in scientific experimentation? (site 1)

The ruler who worked hard to introduce Western social customs into Russia was a. Peter the Great. b. Catherine the Great. c. Michael Romanov. d. Ivan the Great.

The basic unit of life is known as the cell. the nucleus. the neutron. the atom.

Which best explains how the body maintains homeostais? A. All systems work together to match the external environment B. All systems work together to stabilize the body C. Each system works interdependently to stabilize the body D.

It is an effect that drug use can have on society? A. Drug use increases pollution. B. Drug use leads to an increase in criminal activity. C. Drug use increases the spread of disease. D. All of the above

Which of the following affects the speed of light waves in a material? Angle at which the ray strikes the medium Color of the material Density of the material Temperature of the light wave

What does the nosepiece do on a microscope

What does a scale measure