Which lived on the earth a longer time, dinosaurs or mammals?

What links the two strands in a dna helix together in the middle? a. phosphate groups b. sugar rings bonded together c. proteins d. bases with hydrogen bonds

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?

Biology ! the conversion of inorganic carbon to organic carbon by plants during photosynthesis is known as _[blank]_. filtration immigration reabsorption primary production