A student drew this model to show the gas exchange in the human body. What strengths and weaknesses do you see in your improved model?

Which of the following is the source of energy for photosynthesis? a.) glucose b.) chlorophyll c.) carbon dioxide d.) sunlight

There are fewer than 100 naturally occurring elements in the universe, but there are millions of different unified substances. explain how this can be true.

Which of these statements is true about autotrophs, but not heterotrophs? a. they use sugar and oxygen to make carbon dioxide and water. b. they use chlorophyll and oxygen to make carbon dioxide and water. c. they use sunlight, water, and carbon dioxide to make sugars. d. they use sunlight, water, and oxygen to make chlorophyll.