Sarah performs an experiment to determine the effect of nitrogen on plants. she studies the effect of nitrogen on the growth of the root hair, height of the plants, and nodule formation. which factor is an independent variable?

List two limitations of natural selection

During the day, plants produce by splitting water molecules in the light-dependent reactions of photosynthesis. at the same time, plants use cellular respiration to produce some of the needed by the light-independent reactions to make sugars. during the night, plants produce because takes place.

Rarefaction is used for which of the following? a. creating a representative sample b. studying how disease impacts populations c. rediscovering species thought to be instinct d. determining which sea creatures live in an area