The pressure needed to pump blood back to the heart is produced by the

heart
body muscles
contracting arteries

What evidence supports the law of conservation of energy? a) mechanical energy is converted to chemical energy during photosynthesis. b) oxygen is made from the breakdown of carbon dioxide during photosynthesis. c)energy is absorbed by chlorophyll and becomes chemical energy during photosynthesis. d)the sun gives off light energy that is absorbed by plants.

Most animal cells membranes have proteins that pump ions out of the cell and potassium ions into the cell

Ascientist is conducting an investigation that involves water, silver, carbon dioxide, and oxygen gas which group of statements best describes all of the materials he is using in the investigation?