How many species have been identified and named?  Approximately  

Evidence of previously existing life is found in

When a positively charged hydrogen in a water molecule become attracted to the negatively charged oxygen in a nearby water molecule, this is called a ionic bond.

Which one of the following is TRUE with regard to the numbers of subatomic particles in an atom?

List the parts of the scientific method.

Which of the following would be considered the most common element (by weight)  in living things?

All single-celled organisms are prokaryotes

A protein that has had its physical and chemical properties changed is said to be

Why is it important to give an organism a scientific name?

Multicellular, nonphotosynthetic organisms with cell walls are found in the Kingdom