Valves in the veins support the theory that: A: blood moves in two directions through the vein, B: movement of blood is back and forth through the veins, C: blood circulates through the body, D: blood ebbs and flows in one space

How do organisms acquire energy directly or indirectly from sunlight?

What are the cells surrounding the stomata called? A Guard cells B. Mesophyll cells OC Palisade cells

You have designed a drug that is supposed to bind to the myosin binding sites on actin. You inject it into a relaxed muscle, but find that none of the drug bound. Which of the following explains why? A) There are no myosin binding sites on actin.

Which type os landform develops at plate bounderies where one oceanic plate descends beneath another? A. Mountain ranges formed by a batholith B. Rift valley C. lava plateau formed by uplift D. volcanic island arc

What functional groups will be joined together if alanine and serine molecules combine to form a single molecule? (a. an amino group and a carbonyl group.) (B. an amino group and a methyl group.) (D. a hydrogen atom and a methyl group.)

1. Suppose that xylem were located only in the roots and stems of a plant. Would fluids in the xylem still move? Explain.

What activity will decrease body temperature? Sweating Exercising Adding clothing Shivering

Organisms with true radial symmetry A. tend to be highly mobile. B. do not have a distinct head region and tend to be sedentary or passive drifters. C. can be divided into two matching halves along only one plane. D.

1. The Earth's carbon cycle consists of the flow, cycling, and recycling of all of the carbon on the Earth. Every living organism's composition includes the element carbon. How does carbon become part of living organisms?

Which of these is used to find the precise age of a rock? Index fossils Radioactive dating Relative dating Stratified rock layers