Fish are thought to have descended from ostracoderms.

What happens during interphase? (1)the nucleus grows to its full size. (2)the cell grows to its full size. (3)the nucleus divides into two nuclei. (4)the cell divides into two cells.

Explain how sequences of amino acids in proteins can be used to reveal relationships among organisms.

Match the reproductive structures based on their function and the system to which they belong. egg ovary sperm vas deferens vagina fallopian tube testis urethra