Answer:
The elephant and the sheep exhibit higher sequence similarity because they are more closely phylogenetically related
Explanation:
The elephant and the sheep are mammals, while the crocodile is a reptile, being the mammals the most inclusive group among these three species and it appeared later in evolution. Mammals are organisms that have shared evolutionary features such as warm blood, they produce milk and have hair
Answer:
By looking at human embryo we can determine that it has a postanal tail.
Explanation:
Human embryo is a a process of life cycle that takes place after the fertilization. It takes 9 months for a human embryo to be fully developed. If we take a look at a human embryo, we will notice that it has a postanal tail.
Postanal tail is simply an extension of body. It is only during the embryonic stage that the postanal tail can be found. After the birth this feature cannot be found.
Answer:
Explanation:
My best bet is DNA methylation at the site of Tweedledum's leptin gene or Histone Acetylation at the site of Tweedledee's gene.
B/c DNA methylation is a process by which methyl groups are added to the DNA molecule. Methylation can change the activity of a DNA segment without changing the sequence. When located in a gene promoter, DNA methylation typically acts to repress gene transcription. So this is probably repressing Tweedledum's leptin gene trancription which is not happening in Tweedledee.
Additionally, Histone Acetylation at site of Tweedledee's gene increases her trancription b/c Histone acetylation causes DNA to be more accessible and leads to more transcription factors being able to reach the DNA. Thus, acetylation of histones is known to increase the expression of genes through transcription activation.
