Answer: B
Explanation:
carbon monoxide is poison and can kill you
 
        
             
        
        
        
Answer:
Skin is the human body's largest organ.
 Explanation:
Body organs aren't all internal like the brain or the heart. There's one we wear on the outside. Skin is our largest organ—adults carry some 8 pounds (3.6 kilograms) and 22 square feet (2 square meters) of it.
 
        
                    
             
        
        
        
Answer:
E. Gene is amplified by multiplication of cloning host
Explanation:
PCR is a very powerful technique that can help us to amplify exponentially one gene from a very small sample of DNA.
As seen in the attached image, the process begins with a single DNA molecule, for the first cycle, that DNA molecule denaturalizes into two strands, the primers bind to their complementary sides and then the DNA polymerase builds the new DNA strands. The number of copies of the gene that can be obtained with each cycle are 2ⁿ copies, where n is the cycle number. 
 
        
             
        
        
        
In low light no plants grow. With no plants no animals can eat so less animals remain or stay there. With less animals less animals respire and breathe out CO2.