In the current animal classification system is thought to have originated once, and is thought to have evolved multiple times.

Grasses--> mice--> cats--> coyotes suppose 10,000 units of energy are available at the level of the grasses. what is the total number of energy units lost by the time energy reaches the coyote?

The carrier molecules of the electron transport system are located in the

Which type of neuron stimulates muscles to contract?