Animals are classified as either vertebrates or invertebrates based on the presence of a backbone.

What ecological role do plants generally serve in an ecosystem?

The primary function of camouflage in animals is to avoid predation.

Which organ is responsible for pumping blood throughout the body?

Which organ system is responsible for the production of hormones?

How many domains are used in the modern classification system?

What contribution did Elizabeth Bugie make to microbiology?

 Fungi contribute to ecosystems primarily by:

Extra credit:  Outline blood flow through the pulmonary circuit.

What sphincter is this? What is its function?