What feature of the fossil Pikaia led scientists to classify it as a chordate?

A. Tentacles

B. A definite head region

C. A notochord

D. Segmentation

Which is the correct order of the parts through which urine flows in a nephron

Curare is a poisonous plant extract. curare molecules have a chemical structure like the neurotransmitter ach. curare can bind to the ach receptor site on the chemically gated ion channels in the motor end plate.

How do genetic factors influence the formation of "dead zones" around creosote bushes?

A plant nutrients needed in small qualities is called

How do mutations enter the gene pool? Why are they important to natural selection?

What is the main function of cuticle in plants? 1. It prevents water loss. 2. It absorbs sunlight. 3. It protects the plant from predators.

What minerals are found in bone? What do these minerals do for your bones

Scientists developed a new margarine containing plant ingredients they think will lower blood cholesterol levels in people who use the margarine.

Which of the following is a good example of something a cell might do during G1 phase

A square kilometer of forest has 200 deer. What is the term that is used to describe this number?