Answer:
Mitochondrial DNA is the DNA located in mitochondria, cellular organelles within eukaryotic cells that convert chemical energy from food into a form that cells can use, adenosine triphosphate.
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Answer:
B. a food chain
Explanation:
Food chain: a hierarchical series of organisms each dependent on the next as a source of food.
 
        
             
        
        
        
Answer:
Add them!
Explanation:
The mass number of an atom is its total number of protons and neutrons
 
        
             
        
        
        
Answer:
The amount of energy at each trophic level decreases as it moves through an ecosystem. As little as 10 percent of the energy at any trophic level is transferred to the next level; the rest is lost largely through metabolic processes as heat.
Explanation:
 
        
             
        
        
        
Pressure decreases with increasing altitude.