Answer:
Tricuspid valve: Allows blood to pass from the right atrium to the right ventricle; prevents blood from flowing back into the right atrium as the heart pumps (systole).
Explanation:
 
        
             
        
        
        
Answer: They can be either of the same species (intraspecific interactions), or of different species (interspecific interactions). These effects may be short-term, like pollination and predation, or long-term; both often strongly influence the evolution of the species involved. A long-term interaction is called a symbiosis.
Explanation:
 
        
                    
             
        
        
        
Answer:
black is the dominant phenotype.
Explanation:
The black gene "overrides" the gene that codes for blue, thus making it dominant.
 
        
             
        
        
        
Flex to the moon and back