Critical Thinking The gravity of the sun and the moon affects tides
on Earth. The model below shows the positions
of the sun, the moon, and Earth during a spring
tide. Use it to answer questions 8 and 9.
Moon's pull
New
moon
Sun's pull
Sun
Earth
8 Analyze How does this model make it
easier for someone to understand the sun's
and the moon's influences on the tides?
9 Evaluate What do you think are the
limitations of this model?

Study the picture of the ocean. which is the best example of an organism’s niche shown in the picture? a. the environment contains several of the same species of coral. b. the shallow area of the ocean meets the needs of the coral and the fish. c. the ocean has fish and coral that live in the same area. d. the coral take in food from the water and provide shelter for the fish.

Every early childhood education program should develop a

1. an enzyme is considered a(n) because it speeds up a chemical reaction without being used up.2. in a catalyzed reaction, a reactant is often called a(n) . an enzyme is specific because the shape of its matches only particular reactants.4. an enzyme speeds up reactions by lowering the . the between an active site and its substrate often strains bonds and the reaction proceed.6. a( , which is often a vitamin, binds to an enzyme and plays a role in catalysis.7. high temperatures or changes in ph can an enzyme, causing it to lose its shape and biological activity.