It forms the outer layer of a cell. It gives an animal cell its shape. It is selectively permeable. 
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Answer:
D
Explanation:
Carbon is expelled not used for producing sugars or any of that
 
        
             
        
        
        
Answer:
these statements are true 
B) Insertions or deletions of single base-pairs within a protein coding sequence probably change the amino acid sequence
D) Missense mutations always change the amino acid sequence encoded by a gene
E) Nucleotide substitutions outside of the coding sequence can affect the expression of a gene.
Explanation:
B) insertion or deletion of nucleotide in coding region of DNA can change the amino acid sequence encoded. 
D) missense mutation means that the change in nucleotide sequence resulting in change in amino acid sequence encoded by gene. 
E) A mutation may alter the promoter of a gene, thereby affecting the rate of transcription.
 
        
             
        
        
        
Answer:
Hey!
Here's why its important:-
When a foreign antigen reaches one’s blood, it stimulates the defense  mechanism. On receiving unmatching blood, the antigen present  in the donor's blood and the antibody present in the recipient's  blood will react with each other and form a blood clot. Hence,  everyone cannot receive blood from all blood groups.