Primary succession starts with bare rock which is broken down by either lichen or moss to make soil while secondary succession starts with developed soil
the skin covering the human body consists of 2 layers.
Answer:
the answer for this is B.
One option for reducing air pollution is to cut back on major producer factories.
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%
