Unlike arteries, veins contain valves that ensure blood flows in only one direction. (Arteries don't require valves because pressure from the heart is so strong that blood is only able to flow in one direction.) Valves also help blood travel back to the heart against the force of gravity.
Answer:
Sun --> carrot --> rabbit --> wolf --> earthworm
1: Oxidation
<span>2: Potential; Kinetic if physics, Potential; ATP if biology </span>
<span>3: reduction </span>
<span>4: hummingbird </span>
<span>5: butterfly </span>
<span>6: autotrophs; heterotrophs </span>
<span>7: heterotrophs </span>
<span>8: Krebs cycle </span>
<span>9: none of the above </span>
<span>10: absorbing.</span>
Teperature
Ph level
Substrate concentration
Not sure if these are physical but hope it helped.
For animals, hearing is a fundamentally important adaptation for survival, maintenance, and reproduction.