What type of organism is missing from the food chain? a) an organism that would eat the bear. b) organisms that would feed off of the flies. c) organisms that can convert the sun's energy into a useable form of energy. d) there has to be more than one type of organism at the bottom of the food chain.

What are the student's observations and inferences before he starts his investigation?

Which of the following statements is true about the relationship between genetic variation and natural selection? a. genetic variation must be present in a population before natural selection can act on it. b. genetic variation arises in a population as a result of natural selection. c. natural selection can act on a population whether there is genetic variation within the population or not. d. after natural selection acts on a population, the amount of genetic variation in the population always increases.

When fossil fuels are burned, carbon dioxide is released. how does this gas impact the environment?