Do Earthworms have an opened or closed circulatory system? Why?

What characteristic make legumes a good food source for food insecure populations

Identify characteristics of energy from the sun. check all that apply. almost all of the energy on earth comes from the sun. energy from the sun is known as mechanical energy. the energy in fossil fuels originally came from the sun. plants convert the energy of sunlight into chemical energy.

When lactate builds up in a runners muscles it causes a burning sensation what causes this to occur