Answer:
the 1rst and 2nd
Explanation:
all fertile individuals can breed with one another and individuals vary genetically
Answer:
Chemical nutrients and energy tend to flow in the same direction for most of an ecosystem. The big difference is that the chemical nutrients are ultimately recycled in the ecosystem while the energy is ultimately lost from the ecosystem to the universe at large. Energy in any ecosystem ultimately comes from the Sun
Explanation:
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Insulin helps the cells absorb glucose, reducing blood sugar and providing the cells with glucose for energy. When blood sugar levels are too low, the pancreas releases glucagon. Glucagon instructs the liver to release stored glucose, which causes blood sugar to rise.
The pancreas releases glucagon when glucose levels fall too low. Glucagon causes the liver to convert stored glycogen into glucose, which is released into the bloodstream. High BG levels stimulate the release of insulin. Insulin allows glucose to be taken up and used by insulin-dependent tissues, such as muscle cells.p