Valerie hypothesizes that frogs lay more eggs in warm water than in cold water. When Valerie designs her experiment, what should be the only variable that changes?

A.

frog species

B.

time of year

C.

water temperature

D.

water flow rates

Which of the following is found in the ' rungs' of a DNA strand?

Which substance in cigarettes is a thick, brownish sludge containing carcinogens?

The act or process of changing position and/or direction is called OA. distance ОВ. acceleration C. motion D. force

Which line of defense includes active immunity? first second third fourth

What are the 2 processes associated with cell differentiation?

Part 1: Which substance has a higher solubility? Part 2: Explain your answer for Part 1. Julia did an experiment to study the solubility of two substances. She poured 100 mL of water at 20 °C into each of two beakers labeled A and B.

The line of 49 degrees north latitude follows a ... A. National border B. Long river C. Mountain range S. State border

Which molecule crosses the plasma membrane by diffusion? oxygen glucose enzymes all of the above

Listening for sounds within the body defines?

Which characteristic is not shared by eukaryotic cells and prokaryotic cells? A. membrane enclosed organelles B. enzyme controlled reactions C. cell membranes D. cytoplasm