Answer: "Decreasing the salt concentration of the solution lowers DNA's melting point (Tm)" is not a true statement
Explanation:
Increasing salt concentration would lower the DNA's melting point (Tm), not otherwise.
For instance:
- In 8M urea (8M means 8 Moles per dm3), Tm is decreased by nearly 20°C.
- 95% formamide at room temperature would completely denature the double stranded DNA.
Thus, higher concentration of salts like urea or formamide lowers Tm, not otherwise
Answer: the first one
Explanation: the rest are very wasteful :)
B: A mutation in one of G5W's parents, during gamete formation, created an X-linked dominant disease allele.
You need to analyze the sex gametes.
Boys are XY
Girls are XX
If you have an X-linked dominant disease you need only one affected X gamete to have the disease.
The mother has XX' where X' is de affected and reproduce with a healthy man XY and breed unhealthy boys, but because of the heterozygous gametes you could also have healthy ones XX and XY
The correct answer is D.
Seafloor spreading is a process of creating seafloor crust out of volcanic materials that are emerging from the Earth's core at the mid-ocean ridges.
This is made possible by the moving of Earth's tectonic plates.
So: both parents' genotypes (concerning baldness gene) are the same: Bb. Possible genotypes of an offspring: BB, Bb, Bb, bb . bb means non-bald girl or boy. Bb means bald boy or non-bald girl. BB means bald boy or girl. there is 25% chance of conceiving a child with a genotype BB. But there is also 50% chance of conceiving a girl. So the answer is: 25% x 50% = 12,5%
