Answer: 
 
All cells hace a barrier around them that separates them from the environment and from other cell.The barrier is called the plasma membrane,or cell membrane.
 
        
             
        
        
        
Answer:
Directly counting blood cells or tissue cells by using a hemocytometer can determine the concentration of a known volume. Counting the number of colonies that arise on a pour plate can calculate the concentration by multiplying the count by the volume spread on the pour plate.
 
        
             
        
        
        
The answer is
frequency of the homozygous recessive genotype --> q^2
frequency of the heterozygous recessive genotype --> 2pq
frequency of the recessive allele --> q
frequency of the dominant allele --> p
frequency of the homozygous dominant genotype --> p^2
Hope this will help for all
 
        
             
        
        
        
Answer: Incomplete dominance
Explanation:
In incomplete dominance, both alleles are expressed but have become blended giving rise to a new trait with one also been more noticed than the other although both are expressed. For instance a red flower and a white flower are crossed, giving rise to a pink flower. As compared to codominance, both alleles are equally expressed and are equally dominant. For example, a white college crossed with a black hen giving rise to a black and white (checkered) chick.