The changes in the grape juice happened due to the alcoholic fermentation of the grape juice that occurs due to the presence of aerobic bacteria. The presence of yeast is the main reason behind the process of fermentation taking place. The froth is produced due to the presence of the formation of acid and carbon dioxide. 
        
                    
             
        
        
        
A target cell respond to a hormone because it bears receptors
        
             
        
        
        
Air pollution; smoking in the house
        
             
        
        
        
The type of bond formed between carbon and hydrogen is NON POLAR COVALENT BOND.
Covalent bond involves sharing of atoms between two elements; each element will donate electrons which will be equally shared by the elements involved. In the case of carbon and hydrogen, carbon has four electrons in its outermost shell, therefore it will form a covalent bond with four atoms of hydrogen each of which will donate one electron.
        
             
        
        
        
- The question can be solved by using the difference between eukaryotic and prokaryotic cell.
- Prokaryotic cell does not have a well defined nucleus. The nuclear material lies naked in the cytoplasm. It is known as nucleoid. While, eukaryotic cell has a well defined nucleus with a nuclear membrane.
- Prokaryotic cell has a single chromosome while eukaryotic cell has more than one chromosome.
- Finally, prokaryotic cell do not have membrane-bound cell organelles while eukaryotic cell have membrane-bound cell organelles.
Hope you could get an idea from here.
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