Many scientists suggest that billions of years ago,
life on earth began with
(1) simple, single-celled organisms
(2) simple, multicellular organisms
(3) complex, single-celled organisms
(4) complex, multicellular organisms

What did hunter gathers do to alter the environment?

Nerve cells are specialized to respond to stimulitrue or false?

20. in humans, freckles are dominant to no freckles. trey has no freckles and his wife anna grace has freckles, but her dad doesn't. they want to know what percentage of their kids would look like trey. show a punnett square to support your answer.