Answer:
A genetic chain is something your grandparents passed on to your parents, and your parents passed it on to you, and so forth!
Explanation:
 
        
             
        
        
        
The symbiotic relationship in which both participating parties benefit is called mutualism. When one organism benefits and the other organism is harmed it is called<span> parasitism.</span>
        
                    
             
        
        
        
All galaxies have a dense core of stars. Spiral galaxies, however, have arms that are often visible. There are two kinds of spiral galaxies: barred, where there appears to be a line running from arm to arm through the core, and <span>ordinary, where there is no bar. @Badbunnyhunny</span>
        
             
        
        
        
The wall of the heart<span> consists of three </span>layers<span>: the epicardium (external </span>layer<span>), the myocardium (middle </span>layer<span>) and the endocardium (inner </span>layer<span>). The epicardium is the thin, transparent </span>outer layer<span> of the wall and is composed of delicate connective tissue.
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