Answer:
The type of mutation that occurs when in the DNA strand there is a change from guanine to cytosine is a nonsense mutation, since the triplet that should encode the amino acid encodes a stop codon and the protein cannot be completely synthesized.
Explanation:
The nonsense mutation consists of a change in one of the bases of the stranded DNA, which is transcribed into an altered mRNA, producing a stop codon, instead of an amino acid.
In the table it is observed that the CCA codon is a stop codon that cuts off the protein synthesis prematurely, leaving it incomplete and probably non-functional. 
Sometimes this type of mutation can alter the sequence of amino acids but the protein may be complete enough to partially fulfill its function.
 
        
             
        
        
        
1. first one
2. 2nd one 
3. I think the 3rd one?
        
                    
             
        
        
        
I think its C. hormones act on muscles and glands only. Because hormones act on cells, tissues, organs etc. So this is incorrect and the rest of them are correct.
 
        
             
        
        
        
Answer:Francesco Redi was against the theory of spontaneous generation. His intent for performing this experiment was to disprove the theory. He took six jars and filled them with decaying meat. He left three of these jars open and sealed the other three.
Explanation:
 
        
             
        
        
        
Homologous pairs, Eg. X and Y
One pair in paternal and the other in maternal, obtained during Meiosis.