Why are proteins considered organic molecules? O A. They contain many nitrogen atoms.
B. They contain many carbon atoms.
C. They are not used by living things.
D. They are very small.

Match the examples to the correct level of organization. 1. system level roses, snakes, puppies 2. organism level roots, stamens, leaves 3. tissue level bone, cartilage, blood 4. organ level heart, veins, arteries

Temperatures in ponds and lakes vary by season. select the best answer from the choices provided t f

Ascientist is designing an investigation to study the impact of invasive bird populations on local, native bird populations at backyard bird feeders. what population is most likely to be a control group for the investigation? amount of food number of bird feeders invasive bird populations local backyard birdfeeders without food