Answer:
The correct answer is option A. "They only introduce supercoiling and cannot relax a covalently closed circular DNA".
Explanation:
Type II topoisomerases are enzymes that regulate the winding an unwinding of DNA during DNA replication. Basically, these enzymes are the scissor that remove the knots and tangles formed during the replication process. Is false to affirm that type II topoisomerases only introduce supercoiling and cannot relax a covalently closed circular DNA. Bacterial type II DNA topoisomerases work with the circular DNA of bacterium by changing the linking number of circular DNA by ±2.
Answer:
0%
Explanation:
Achondroplasia is an autosomal dominant disorder that is expressed in both homozygous and heterozygous dominant genotypes. Since two affected parents have a normal girl child, both the parents should be heterozygous carrier for the disease. Let's assume that the dominant allele "A" is responsible for the disease. Genotype of both the parents of the girl would be "Aa". The genotype of girl with normal stature is "aa". Genotype of her normal partner is "aa".
A cross betwee aa X aa would get all the progeny with "aa" genotype. Therefore, all of their children would have normal stature and there is 0% probability for them to have a child with achondroplasia.
Answer:
This is an example of "Disruptive selection".
Explanation:
<em>Disruptive selection</em> occurs when <em>selective pressure</em> <em>favor homozygous</em>. In equilibrium, <em>the two alleles might be present or one of them might be lost</em>. If an environment has two extremes, then in these environments, both alleles are presented in homozygous.
The disruptive selection causes an <em>increase</em> in the two types of <em>extreme phenotypes over the intermediate forms</em>. Limits between one extreme and the other are frequently very sharped. Individuals belonging to one phenotype can not live in the same area as individuals belonging to the other phenotype, due to the traits differences between them, competition, or predation.
Populations show two favored extreme phenotypes and a few individuals in the middle. Individuals who survive best are the ones who have traits on the <u>extremes forms</u>. Individuals in <u>the middle</u> are not successful at survival or reproduction.
<em>Color</em> is very important when it comes to <em>camouflage</em>. Dark green caterpillars that live in dark foliage and light green caterpillars that live in light foliage can <em>hide from predators</em> more effectively and will live the longest. Intermediate colored green caterpillars that don't camouflage or blend into either will be eaten more quickly.
