A tissue.
Then a group of tissues that work together is an organ.
The a group of organs is an organ system.
A group of organ systems is and organism.
Coenzymes
Coenzymes are small organic molecules that, themselves, do not function as catalysts (i.e. enzymes) but aid the latter in carrying out their functions. Enzymes are biological catalysts, which means that they allow reactions to occur at lower activation energies. In a way, enzymes help to "speed up" chemical reactions.
Coenzymes are mostly derived from vitamins. Examples include TPP from Vitamin B1 (thiamine), FAD from Vitamin B2 (Riboflavin), and NAD+ from Niacin.
The condensation of water vapor formed the early oceans. It is an important part of the water cycle. It is easy to eliminate the other answers in this question. It can't be meteorites, living organisms, or nitrogen.
Answer:
For example, addition of an orange chromic acid reagent to some compounds causes the chromium reagent to change to a blue-green color (Figure 6.37a). This is considered a "positive" test result, and in this case indicates the presence of a functional group that can be oxidized (alcohol or aldehyde).
Answer: 1, 2, 4 are accurate.
Explanation:
1. Joe is on a hill (on a trail) above the ocean. The beach and ocean are at similar altitudes. Therefore Joe is at a higher altitude than if he was at the beach.
2. Since Joe is on a hill, he has a higher altitude than at sea level. Air at a higher altitude has lower density because there is less air "ontop" of itself than at lower altitudes. As well, his hill is above the ocean, which means there is a lot of water, making the air more humid than where he is. Humidity also makes air denser.
4.The air pressure will decrease if Joe goes up to higher altitudes because there will be less air on top of itself.