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.
Virions are physical entities containing nucleocapsid, capsid and sometime envelop. It exists extracellularly. Viruses are genetic material that occur intracellularly
Answer:
a. Stabilizing selection
Explanation:
Babies lower than 5.5lbs would suffer from various disorder because of low birth weight as their body would not be able to compete as well they would have weak immune system and malnourishment. Whereas high birth weight carry the equally above risk as their body wont be able to cope up and organs become insensitive to various hormones. for the survival the birth weight should be within a median range so that it would be favorable for themselves and surroundings.
Stabilizing selection occurs when a population stabilizes on a particular trait value and genetic diversity decreases. As in this example, an average baby weight has to favour against extreme variation for it's better survival.
therefore, this is an example of stabilizing selection.
Some characteristics that is shared is a soft body and an outer shell to protect their body.
Answer:
1. gravel of the sand: a part is dissolved and the remainder is grouped at the bottom of the beaker.
2. drop of sunflower oil: It is not absorbed and heaps on the surface of the water contained in the beaker.
Explanation:
Gravel of the sand is a polar substance. This means that this substance has the ability to dissolve and mix with water in a system in which both were placed together, such as a beaker, for example. However, the beaker limits the amount of water, which limits its ability to dissolve polar substances. Therefore, depending on the quantity, the gravel of the sand, when placed in a beaker with water, will dissolve, in parts, what is not dissolved will accumulate in the bottom of the beacker, because the gravel of the sand is denser than the water.
With the drop of sunflower oil the exact opposite happens. This is because drops of oil are nonpolar substances, which means that they do not have the ability to be dissolved in water. This means that when dropped into the beaker with water, the drop of sunflower oil will not dissolve, but will pile up on the water surface, because it is less dense than water.