Answer:
25%
Explanation:
When looking at a pedigree remember that:
- squares are males
- circles are females
- the solid colored figure represents an individual affected by a disease
- the empty figure represents a healthy individual
Let us assign the symbol X⁺ to represent the dominant allele linked to the X-chromosome and expressing healthiness, and X⁻ to represent the recessive allele expressing the dissease.
According to this pedigree
- I1 is a man affected by the disease, YX⁻
- I2 is a healthy woman X⁺X⁻
- we can see that among the progeny (generation II) there are two individuals affected (a boy and a girl) and one healthy girl. This means that the mother I2 is heterozygous for the trait.
So, having their genotypes we can know what are the probabilities of getting a son with DMD
Parentals) YX⁻ x X⁺X⁻
Gametes) Y X⁻ X⁺ X⁻
Punnett square)
X⁺ X⁻
X⁻ X⁺X⁻ X⁻X⁻
Y X⁺Y X⁻Y
F1)
- The probabilities of getting a healthy daughter X⁺X⁻ are 25%
- The probabilities of getting a healthy son X⁺Y are 25%
- The probabilities of getting a daughter with DMD X⁻X⁻ are 25%
- The probabilities of getting a son with DMD X⁻Y are 25%
<em>yes it is right because if we take example of viruses and germs .. new germs and viruses are much modified as compared to old ages because they adopted the ways they can escape from the immunity.. they have an adoption to transmit their DNA material ,also they can take protein coat of host because of which host's immunity cells cannot recognize germs as foriegn particle..and in this way germs and viruses remain for a long time in body due to the adoptations according to age and environment..</em>
Nuclear reactions emit a lot of radiation.
Answer:
Nothing
Explanation:
A. Control variables generally entail little or no system change. To see if the method worked, the researchers required a positive control in which the heat-killed virulent bacteria invariably transformed the non-virulent microorganisms. This positive control involves adding "nothing" to both the heat-killed virulent bacteria before mixing them with the non-virulent bacteria.