gas exchange is a primary example of simple diffusion,the exchange of *oxygen* and *carbon dioxide* fuels the cellular processes such as photosynthesis and cellular respiration
The correct answer would be D
Key is to lock as D. Substrate is to active site.
This figure illustrates 3 hypotheses of how a cancer stem cell may arise: (1) A stem cell undergoes a mutation, (2) A progenitor cell undergoes two or more mutations, or (3) A fully differentiated cell undergoes several mutations that drive it back to a stem-like state.
Answer:
Pluto is big enough to be considered a dwarf planet, but it has not been classified as such in some peoples views such as Quaoar and Sedna.
Explanation:
The both reach the otter layers of the solar system just like Pluto and are as I said above big but not big enough to be considered a dwarf planet
