18.A___ is a chemical substance that organisms require to live.

Awater molecule is polar because there is an uneven distribution of these between the oxygen and hydrogen atoms.

Akrabby blind whale has married pearl who has normal vision. oneof their two sons is also colorblind. what arr the genotypes of the parents?

Which of the following statements about archaea and bacteria is true? a. neither is single-celled. b. they both have nuclear membranes. c. neither reproduces by binary fission. d. they both lack a nuclear membrane.