Mucous membrane and cilia lining the respiratory tract fight microorganisms by:

A little girl steps on a sharp shell at the beach. What nerve pathway will this stimulus signal follow in order to lift her foot from the sharp object? a. Sensory neuron, interneuron, motor neuron, effector b.

True or false mass is measured in pounds

If a paramecium caudatum swims from a hypotonic to isotonic environment, will it's contractile vacuole become more active or less? Why?

Which of the following statements about eutrophication is NOT true? (A) It is caused by acid rain. (B) It is caused by the addition of nutrients to a water system. (C) It is most harmful when there is little flow through in the system.

What is the primary source of energy in a food chain 1. oxygen 2. sun 3. Carbon dioxide 4. water

By what process do all living organisms grow and repair themselves?

What is the name of the heart's contraction?

Which describes the habitat of a frog?

The size of a population refers to the

An electric current will always follow a. the path of least resistance. b. a path toward the north pole. c. a path toward the south pole. d. the path that leads through insulators.