2. compare: what structures are present in an animal cell, but not in a plant cell?

Animal cells have lysosomes and centrosomes

Plant cells have plasmodesmata, a cell wall, a large central vacuole, chloroplasts, and plastids.

when atoms of different types of elements join together, they make molecules called compounds. water consists of compound molecules made up of 2 hydrogen atoms and 1 oxygen atom. this is why it's called h2o. water will always have 2 times the number of hydrogen atoms as oxygen atoms.

during the process of dna replication, brdu can replace thymidine and incorporate into the newly synthesized dna, cell proliferation thus can be reflected in the extent of brdu incorporation.