The hollow impression of a trilobite is an original remains fossil.
need options so i cant answer
Answer:
Natural selection disrupts the genetic equilibrium by favoring the genes for the traits that impart survival advantage to individuals.
Explanation:
Natural selection refers to the unequal survival rate of individuals of a population due to the presence of some beneficial adaptive genetic trait. These individuals are able to survive more and leave more progeny. Over generations, the population has increased number of these individuals leading to evolution of a population with different allele frequencies.
For example, the frequency of gene for antibiotic resistance in the bacterial population was increased once humans started using antibiotics to control the bacterial population. This led to the evolution of the bacterial population with antibiotic resistance.
B is correct the births exceed deaths
Answer:
If a DNA molecule has 30% Adenine the percentage of the other bases is Thymine: 30% Cytosine: 20% Guanine: 20%.
Explanation:
When the percentage that a base has in a DNA molecule is given, the percentage of the other bases can be known using the Chargaff's base pair rule.
A DNA molecule has the information of the genome of a living being, according to a specific sequence of its nitrogenous bases adenine, guanine, cytosine and thymine.
Chargaff was able to establish that in a DNA molecule the ratio of purine : pyrimidine of 1:1, so there must be the same amount of thymine as adenine and a similar amount of guanine for the cytosine, taking into account the complementarity of bases.
Taking into account the law of the base pair, if in a DNA chain there is 30% of Adenine, in the molecule there is:
- <em>Adenine 30%.
</em>
- <em>Thymine 30%.
</em>
- <em>Cytosine 20%.
</em>
- <em>Guanine 20%.
</em>
- <em>Total ..... 100%
</em>
In this case, the <u>Chargaff rule is useful to determine the percentage of nitrogenous bases that exist in a DNA molecule, knowing the percentage of a single base</u>.