A (an) is a procedure that changes only one variable at a time and keeps others constant

What was the purpose of miller and urey's experiment? a. to find out of prokaryotes evolved from eukaryotes b. to determine whether prokaryotes have cell membranes c. to measure the number biological molecules on earth d.

Trait, bacteria, plant cell, animal cell characteristics of cells

Which of the following does NOT promote speciation? a. gene flow b. season of fertility c. natural selection d. genetic drift

An organism that has adapted to surviving in both salt water and fresh water would be best suited to survive in which aquatic ecosystem? the intertidal zone a river an estuary the open ocean

Give two examples of organisms that differ greatly in their biotic potential

10. What is a genotype? A an organism's combination of genes for a trait B an organism's appearance as a result of its genes C the ratio of dominant to recessive genes in an individual D the collection of dominant genes in an organism

How much of a person's weight is water?

What are the two components of the central nervous system in vertebrates?

A river has a large amount of algae growing. Which most likely caused the growth?

Which of the following statements is true? Natural energy sources are nonrenewable and being depleted. Current fuels are not polluting the air. Mercury released into aquatic ecosystems comes from rock erosion.