An independent variable is that which is: A. Kept constant.
B. Observed to develop a hypothesis.
C. Changed by the scientist.
D. Measured by the scientist.

M! (1). what are the inputs and the outputs for cellular respiration? (2). what is the primary source of energy for cellular respiration?

When is a hurricane considered to have made landfall? a. when at least one inch of rain occurs b. when the eye reaches the land mass c. when the outer wind bands make landfall d. when it moves inland from the coast

Which of the following statements is true? a. the main cause for speciation is an increase in gene flow. b. organisms that reproduce asexually are not considered part of a species. c. on a tree of life diagram, speciation is shown by the merging of two different lineages. d. the size of the geographic area inhabited by a population can cause speciation.