The primary functions of the digestive system are to break down food, absorb nutrients and excrete wastes. Once food is absorbed, what system is responsible for carrying the nutrients to the body cells? OPTIONS:
- respiratory system
- circulatory system
- nervous system
- skeletal system
A: circulatory system

Which of these characteristics best helps scientists classify organisms? OPTIONS:
- size
- color
- gender
- structure
A: structure

Living organisms require energy for biological processes. Chemical energy in a plant cell is OPTIONS:
- produced in vacuoles.
- converted from solar energy.
- developed by centrioles.
- stored as kinetic energy.
A: converted from solar energy.

In a forest community, trees produce leaves that can be eaten by deer. The leaves also fall to the forest floor during autumn. Fungi break the leaves down into nutrients that enter the soil. What is the decomposer in this forest community? OPTIONS:
- the soil
- the deer
- the trees
- the fungi
A:
the fungi