In nucleotide excision repair, damaged dna is excised by what enzyme(s)?

The elephants represented in lanes 3 and 5 could have been a match to the ivory sample if you failed to amplify one allele in ei

olga_2 [115]

About the question:

I failed to find the result of the PCR / electrophoresis. However, I will try to explain when to still consider a sample, and when to exclude it.

Answer:

Probably elephants 1, 2, 4, and 6 exposed a pattern of lines that differed in most alleles from the ivory´s pattern. So they were considered to be different and, hence, excluded. However, elephants 3 and 5 only were different in one allele, which might be due to the amplification failure. In these last situations, the experiment must be run again, and include many markers.

Explanation:

The genetic profile is the series of alleles, characteristic of each individual, concerning a series of DNA fragments.

Once genetic profiles are obtained by using PCR/electrophoresis, they must be subjected to interpretation. The researcher must compare profiles to find concordance between individuals or the lack of it.

In the exposed example, probably we have a profile of the ivory sample, and we need to find out to what individual or population it belongs to. So we need to compare the pattern of bands of the different lanes with the ivory´s pattern of bands.

In resumed terms, if the ivory´s patterns completely match with another lane pattern, then this is the individuals or population to whom it belongs the ivory. However, if they do not match, we need to exclude this individual.

But this is not as easy as it looks like. Sometimes it is difficult to interpret the results because bands are not so clear, and sometimes there are failures during amplification, as said before in the statement of the problem.

In these situations, what you need to do is look for the lanes that match the most with the ivory one and discard those that differ the most. These last patterns probably belong to a different animal or population, that why they can be excluded. Individuals suspected of being the same as the individual understudy or belonging to the same population, must be subducted to a repetition of the study. Also, the use of several markers in the study increases the matches chances.

So, in the exposed example, if the amplification fails in one allele, elephants 3 and 5 could be a match to the ivory sample, probably because all the other alleles do match. You can only exclude them if, after the experiment repetition, the involved allele is still different. On the other hand, you can eliminate the elephants 1, 2, 4, and 6 because their pattern bands are significantly different from the ivory´s patterns, so you do not even need to repeat the experiment.

7 0

2 years ago

Which organic macromolecule is used for long-term energy storage?

user100 [1]

B.)deoxyribonucleic acid

4 0

2 years ago

Would the liver cells that develop from the mutated cell have the same mutation

Anettt [7]

Yes because why a cell goes through mitosis the DNA is an exact replica, there forever having the same mutations

3 0

2 years ago

Consider a species of sparrow that originally lived only in Alaska but recently expanded its range through North America, then C

Shtirlitz [24]

Answer:

North America is the one with the highest heterozygosity frequency for most loci, followed by Central America, and finally, South America with the lowest heterozygosity level.

Explanation:

Some different forces or mechanisms might alter H-W equilibrium and lead to evolution, such as mutation, natural selection, migration, and genetic drift.

In the exposed example, we have a species of sparrow that migrates from Alaska to North America. Migration is unidirectional, which means that the movement occurs in only one direction: from Alaska to North America. We should also consider that the first immigrants colonized the area for the first time, meaning that there was not a receiving population of the same species already established. Finally, we need to consider that Alaska´s environmental conditions are very different from North America´s environmental conditions.

When a species arrives at a new place, it needs to adapt. The establishment and dispersion of the species in the new area depend on previous adaptation. So, when the firsts sparrow individuals arrived in North America, they faced new environmental conditions that acted as selective pressures that drove to the occurrence of mutations. A mutation implicates a stable and inheritable change in the genetic material. A mutation introduces changes, new alleles in the population, variability. But mutation rates are very low and have no evolutive direction, so they need another force to increase or decrease the mutant allelic frequencies. Natural selection benefits new advantageous alleles and transmits them to new generations changing their relative frequencies. <em>So, sparrows arrive in North America, mutated, and natural selection favored the beneficial mutations leading to a better adaptation to the environment.</em> This means that the heterozygosity level in this new recent population is very high.

As animals adapt to the new habitat and have better dispersal genes, they get to disperse even more. So they start new migration south, to Central America and South America. Again, they are moving to new regions with new conditions, and to establish they need to suffer new adaptations. But remember that we are talking about a recent event in time. Probably the animals migrating south are just a few. They have not spent enough time yet in the new area, to adapt to the new environment and to include new genes into their population. What is even more, as they are a small new population moving south, they are more vulnerable to genetic drift events. Genetic drift acts on a population decreasing the variability between individuals, hence, decreasing the heterozygosity. <em>This small population suffers low mutation, has not enough time to establish, and is more vulnerable to genetic drift events.</em> The heterozygosity level is probably inferior to North America´s one.

Comparing the three areas, we could say that North America is the one with the highest heterozygosity frequency, followed by Central America, and finally, South America with the lowest level of heterozygosity.

8 0

2 years ago

3. Use the following question in a sentence. DO NOT simply give the

Drupady [299]

Carbon dioxide is a colorless and non-flammable gas at normal temperature and pressure. Although much less abundant than nitrogen and oxygen in Earth's atmosphere, carbon dioxide is an important constituent of our planet's air. A molecule of carbon dioxide (CO2) is made up of one carbon atom and two oxygen atoms. Carbon dioxide is an acidic colorless gas with a density about 53% higher than that of dry air. Carbon dioxide molecules consist of a carbon atom covalently double bonded to two oxygen atoms. It occurs naturally in Earth's atmosphere as a trace gas.

7 0

2 years ago