The picture shows a model being used to explain how food is moved through the gastrointestinal (GI) tract. What do the fingers pushing the marble along represent? f The pressure of blood vessels surrounding the GI tract
g The production of fluids by the GI tract
h The contraction of muscles in the GI tract
j The electrical impulses from the nervous system to the GI tract

Choose the molecule that is described by each phrase. energy used during long activities:

Which of the following is the best definition for the process of photosynthesis? a.) plants digest sugars to make energy. b.) plants use oxygen and glucose to make carbon dioxide. c.) plants use sunlight and carbon dioxide to make sugars. d.) plants use sunlight to make chlorophyll and chloroplasts.

Step 1 review the imaginary strand of dna below. note the complementary base pairs. a g c a a t c c g t c t t g g t c g t t a g g c a g a a c c step 2 to begin replicating this strand of dna, draw the two sides of the strand separating. step 3 now, draw the free-floating bases linking up with the separate sides. remember to follow the rules of complementary base pairing. step 4 draw the two resulting dna strands.