20. Cell Membrane 19. Mitochondria 18.<span> Osmosis</span>
        
                    
             
        
        
        
The benefits of artificial selection is that you've taken the traits that you desire from a plant or an animal that could benefit your own survival. (Much like our ancestors bred the highest/most efficient crops, leaving us in a good farming position today). However, the drawbacks of artificial selection is that you effectively destroy any natural selection or "survival of the fittest" thus reducing the gene pool. If a virus or bacteria was effective against a crop that we bred, it would destroy our entire farming industry (also works with animals that we breed). 
        
             
        
        
        
Answer:
D is the answer.
Explanation:
 The deeper into Earth's crust, the higher the pressure that forms metamorphic rocks.
 
        
             
        
        
        
Answer:
A. A segment of DNA molecule
Explanation:
(a sequence of bases) that codes for a particular protein and determines the traits (phenotype) of the individual. A gene is the basic unit of heredity in a living organism.
 
        
                    
             
        
        
        
Answer:
The fact that only cells are able to produce more cells is part of cell theory. The idea that organisms can develop independently of cells is called spontaneous generation, and it isn't supported by cell theory. Spontaneous generation suggests that living organisms develop from non-living matter.