Answer:d
Explanation: because it encompasses all other levels if you see
Answer:
Low phenylalanine concentration:
- If the enzyme is inactive, PAH will look like its inactive form, with phenylalanine located in the allosteric site / inactive site so that PAH is a different shape. This will not allow as much phenylalanine to be converted into tyrosine, as we wait for Phe levels to increase.
High phenylalanine concentration:
- If the enzyme is active, PAH will look like its regular form, with an open active site that's the size of phenylalanine so that reactions can occur. (Like a hand fitting into a glove, or a lock into a key.) Phenylalanine will be the substrate, the thing acted upon by the enzyme. This will eventually raise the amount of tyrosine that's created and lower the concentration of phenylalanine.
Think about it like this. Ever heard of homeostasis? That's how the body likes to be the same, keep everything regulated, all the time. So if there are high levels of something, the body is going to try to keep that something down, and if there are low levels, it's going to try to increase the concentration of that thing.
It illustrates the cycling of matter, just like in a natural ecosystem.
Option D.
<h3><u>Explanation:</u></h3>
The natural stable ecosystem is defined as the ecosystem which has the members doing their part of job and each and every member contribute to the stability of the ecosystem by completing food chains.
Here in this bottle ecosystem the boy put the stones, rocks, water which gives proper nutrition to the growing plants and animals which are also introduced by the boy. The plants produce oxygen and consume carbon dioxide whereas the animals consume oxygen and produce carbon dioxide. Thus the cycle is maintained and stability is achieved.
