The “rungs” of the helix are made of which are joined by bonds. The “backbone” is made of and and is joined by bonds.

Use this diagram of an animal cell to answer the question. where does the first stage of cellular respiration occur? w x y z

What causes darkening of the skin as melanin production increases

The fruit of a certain plant is sweet and fleshy. the seeds of this plant have a seed coat that is fairly tough. the seeds germinate better if they are exposed to acid, or scarification. what is the most likely type of dispersal for this seed? water animal wind