Shells are the exoskeletons of clams, snails and oysters. Hope that helps
Answer:
Because it usually takes a long time, and is a very long process.
Explanation:
Answer: Sea stars move using a water vascular system. Water comes into the system via the madreporite. It is then circulated from the stone canal to the ring canal and into the radial canals.
Explanation: The radial canals carry water to the ampullae and provide suction to the tube feet.
One of the major elements of natural selection is that all species have genetic variation. Natural selection is a process when organisms adapt better to their environment. It is an essential key in evolution. There is a change in phenotype of a population over time.
Answer:
Renewable resource: Sunlight, water, wind,
Norenewable: coal, natural gas, oil
Explanation:
Hope this helps
