<span>It is the variable in an experiment is not directly altered</span>
Answer is: each base can attch to only one other type of base
Answer:
Explanation:
It is given that
B is the dominant allele which represents the black color
and b is the recessive allele which represents the white fur.
B being dominant will result into black color fur for genotype "Bb"
Given -
Frequency of black fur allele (p) is 
As per Hardy Weinberg's first law of equilibrium
Substituting the value of p in above equation, we get -
q represents the frequency for white fur allele
Frequency of white fur phenotype is
Frequency of homozygous black fur phenotype (BB) is
As per Hardy Weinberg's second law of equilibrium -
Combined frequency of homozygous and heterozygous black fur phenotype is
Answer:
The colonies are carrying the resistance genes from plasmids
Explanation:
Bacteria can acquire beneficial characteristics that they didn’t have. One way for these is through plasmids, which ones are little fragments of DNA that usually contains resistance genes (for antibiotics, disinfectants, heavy metals, etc.) or other capacities, like the ability to use some substances (for example sugars).
In this specific situation, we already know that the plasmid carrying genes for tetracycline resistance and the <em>lacZ</em> gene.
A little explanation:
Tetracycline is an antibiotic that inhibits bacterial growth and kills the bacteria. The bacteria can “fight” to this antibiotic if it has a resistant gene, the result is that the antibiotic can’t affect the bacteria and survive. An analogy is like a Police Officer (bacteria) that have a bulletproof vest (tetracycline-resistant gene) so the bullets (tetracycline) didn’t affect the police.
In the case of X-gal, is a compound consisting primarily in one sugar called galactose. Not all bacteria can eat galactose, they need an enzyme called β- galactosidase (comes from <em>lacZ</em> gene) that helps the bacteria “eat” the sugar (cuts the sugar in little pieces so the bacteria can eat).
Then, as the bacterial colonies can grow in the medium with tetracycline and X-gal, we know that those bacteria are carrying the resistance genes for tetracycline (does not affect the bacteria) and the <em>lacZ</em> gene (bacteria produce β- galactosidase that cuts galactose). These genes are coming from the plasmids because we already know that the plasmid carries these genes and not from the exogenous DNA.
