Answer:
B. Producing milk now requires electricity.
Hope this helps 
 
        
                    
             
        
        
        
Answer:
Si refrigeramos o congelamos el alimento, las bacterias presentes en ellos tendrán un metabolismo más lento, incluso llegando al punto de la muerte por encima de temperaturas a las cuales no les es posible vivir. Es importante mantener la cadena de frío para que las bacterias no tengan lugar a su reproducción. 
Explanation:
Las distintas bacterias que pueden estar presentes en los alimentos tienen distintos parámetros que hacen que sea posible su vida y reproducción. En cuanto a la temperatura, es un factor muy importante ya que podemos encontrar bacterias termolábiles o termoresistentes según puedan vivir en las variaciones de temperatura. La mayoría de ellas no resiste temperaturas frías de refrigeramiento o congelamiento, motivo por el cual los alimentos se conservan así. De esta forma reducimos el riesgo de padecer Enfermedades de Transmisión Alimentaria. La cadena de frío por su parte permite que esa temperatura sea constante a lo largo de todo el procesamiento, transporte y disposición de los alimentos.
 
        
             
        
        
        
Answer: First, an animal eats another organism. Then, food is broken down into smaller molecules. Next, the animal's cells use molecules to make new cells. Animals produce a substance called insulin, which helps them maintain healthy levels of glucose in their blood.
Explanation:
 
        
             
        
        
        
Answer:
C.The added epitope disrupts the function of the tagged protein
Explanation:
When an additional sequence is tagged to a protein to use comercial antibodies, there are several reasons why this procedure wouldn't work as expected (note that we're assuming the protein is being expressed but it's not possible to detect it). 
For example, the sequence of nucleotide added to codify for the tagged epitope are removed during the RNA processing. In that case, the protein would be expressed without the epitope, so it would be impossible to localize it with the antibodies.
Also, it could be that the new epitope is affecting some way the protein folding, making it not functional. This way, it would be degraded by the cell so it wouldn't be detected. 
Another possibility is that the epitope doesn't affects the protein folding nor its function, but during the folding ends up in a conformation that makes it inaccesible for the antibody.
In summary, the way as the possible answers to this question are shown, the correct option seems to be C:<em> The added epitope disrupts the function of the target protein.</em>