The answer is stabilizing selection.
<span>Sickle-cell anemia is a recessive disorder caused by the presence of two recessive alleles "s", so genotype is "ss". This disorder is characterized by sickle hemoglobin. In an area with malaria, heterozygous individuals "Ss" (with one dominant allele and one recessive allele) have an advantage. These individuals will have both normal and sickle hemoglobin. But pathogen that causes malaria affect only normal hemoglobin, so heterozygous individuals will have half of the hemoglobin resistant to the pathogen and those individuals are resistant to malaria.</span>
Stabilizing selection favors heterozygotes Ss, disruptive selection favors dominant (SS) and recessive (ss) homozygotes, while directional selection favors dominant (SS) or recessive (ss) homozygote. Since in this example, people with genotype Ss (heterozygotes) are in advantage, then this is an example of stabilizing selection.
The four factors that affect evolution are mutations, natural selection, genetic drift and the gene flow, In the case, if the ground finches that Grants studied, we can observe the working of the natural selection. Due to change in the conditions in the environment, the large beak was an advantageous trait that was favored by the natural selection. The result of this process was an increase in numbers of large beaked finches and decrease in small-beaked finches compared to the initial numbers in the population.
The answer to this question is Paradoxical sleep.
Paradoxical sleep is the stage of sleep where in the person’s muscles are
relaxed and this is the stage that is called a dreaming sleep. In this stage of
sleep the person is in deep sleep state.
Hello there,
<span>A snake is about to eat some small eggs it has found in a bird's nest. A hawk swoops down and eats the snake. What is the role of the hawk?
I believe that your correct answer would be "</span><span>Tertiary consumer".
Hope this helps.
~Jurgen
</span>
Answer:
According to the genetic code, the amino acids are the following:
- Glycine: encoded by GGC, GGA and GGG codons
-Arginine: encoded by AGA and AGG codons
-Lysine: encoded by AAA and AAG codons
-Glutamic acid: encoded by GAA and GAG codons
Explanation:
The probabilities to observe an amino-acid formed by Glutamic acid in the coding sequence is 2/9 for each codon
