Answer: Rivers
Explanation: Runoff from cars and other pollutants usually flow off of roads into rivers or streams that usually lead into bigger bodies of water such as oceans.
Answer:
3 - Photoreceptors.
Explanation:
Photoreceptors are a sensor that is connected to your retina. They sense light and send the message to your brain. The sensors automatically squint your eyes if something will blind you.
The correct answer is 'photoreceptors'.
The atria of the heart merely need to allow blood to flow into the ventricle, and therefore aren't very muscular.
The ventricles of the heart need to actually pump blood to the rest of the body, whether to the lungs or the the rest of the body.