You have an ecosystem with the following organisms: birds, fruit trees, tigers, and monkeys. which list would best describe the food chain?

The priority list will be like this

Fruit TreesBirds MonkeysTigersExplanation:

In an ecosystem, producers are the first level of the food chain. And we know that plants are producers because they produce their own food. So, fruit trees will be at the beginning of the food chain. After producers comes the primary consumers. Primary consumers are animals that feed on producers. Both birds and monkeys feed on fruit trees, so they are the next in line after fruit trees. Finally, secondary consumers eat primary consumers. As tigers eat animals i.e monkeys etc so they are secondary consumers, and thus they are last on the food chain list.

We can use solar powered cars or ride bikes instead of cars that burn fossil fuels

Atp is is our little "pocket" of energy. of course, if you have too little, then it means you have too little energy, and you'll pass out. the way to not have enough, is to have no energy sources (glucose, fats, proteins). you can't have too many atp molecules. cycles like the krebs cycle produce it, but if you have too much of any substrate (or too little for that matter), the cycle stops and atp is no longer made (it stops until substrate levels are such that the process can go on). in any case, this is unlikely since atp is constantly hydrolyzed and remade, even while you're asleep. you won't have too much. if you have zero, you are dead or dying.