Carbon dioxide is released through
a. burning of forests
c. combustion of fossil fuels
b. respiration
d. all of the above

If a strand of dna has 35% thymine. what is the percentage of cytosine, adenine, guanine?

An ecologist studied the same species of deer during the summer and the winter. she noticed that during the summer, when there was plenty of food, the deer were energetic and playful. however, during winter when food was scarce, the deer moved more slowly and did not run unless they needed to escape a predator. which scientific fact is best supported by her observations?

Which description shows competition in an environment? an organism that feeds on some food an organism that finds a place to sleep three organisms of the same species living in an area three organisms battling over limited resources