Im not 100% sure but the best answer I can give is Prokaryotes because they came to be around the time oxygen did as well.
Compare the limbs of different organisms goes in left box. compares fossilized structures to living organisms left box.
other 2 go in the right box hope this helped(:
Answer:
D. A brown gas produced
Explanation:
When a chemical reaction occur, there are several changes that takes place such as change in color, odor change, formation of a gas, and formation of a precipitate etcetera.
In the given chemical reaction, two colorless gas (NO and O2) react together and form brown gas (NO2). So, the change of gas from colorless to brown gas is the evidence that shows chemical reaction occurred.
Hence, the correct option is "D. A brown gas produced".
Answer:the villi of the intestine
Explanation:like the cristae of the mitochondria which increase the surface area for the production of ATP,the villi of the intestine acts similarly.
In animals, digested food pass from the stomach to the intestine. In the intestine , enzymes acts on the food. Absorption of food takes place there and there are some structures that facilitates it. The walls of the intestine have numerous foldings , alongside the presence of finger like projection called villi. Microvilli are also presence from the cell walls of the intestine . These projections increase the surface area for the absorbing of food .they brush against food in the intestine and promotes absorption of nutrients.
