The ancient Egyptians used the stars to tell when a flood was going to happen. Every summer a flood would happen but this also happened when the bright star Sirius rose before the sun.
Hope that helped ^^
Vasoconstriction
Definition-The blood vessels under your skin become narrower. This decreases blood flow to your skin, retaining heat near the warm inner body.
Answer: These animals eat algae in the water.
Explanation: They clean the water in other words.
Phototropism as photo means light
eg: photosynthesis