Answer:
C. Disruptive Selection
Explanation:
Disruptive selection occurs when two extremes of continuous variation are favored more than intermediate traits.
The extremes of continuous variation exhibited in this species of snail is the color of their shell which allows them to blend with the background of their habitat.
The shady forest of the habitat makes the dark-shelled individuals to be better hidden from bird predators, while the light-shelled individuals are better hidden in well-lit brushy edge areas. This disruptive coloration exhibited by both individuals makes both individuals of this species of snail less vulnerable to predation.
Both individuals of this species both extremities would naturally survive in this habitat as snails with intermediate extremities would be highly preyed on since there is no area of intermediate brightness in the habitat to make them invisible to predators
Question: Describe how a single amino acid substitution causes hemoglobin molecules to stick together. Use what you know about the structure of Hb and HbS, the properties of glutamic acid and valine, and how hydrophobicity causes molecules to behave in water.
Answer:
A Single amino acid must be polar to attract, just like water.
Explanation:
Sickle cell is an genetic illness and it is began by a alteration that arises in the beta sub units of the haemoglobin. Haemoglobin is a tetrameric protein made up of 2 alpha sub units and 2 beta sub units and it is the important part of the blood accountable for oxygen passage. Sickle cell is a illness that consequences from a replacement of a polar amino acid identified as glutamate with a non polar one valine at site six of the beta polypeptide component of haemoglobin. The replacement occurs as a consequence of a alteration in one of the bases in the beta-globin gene from adenine to thymine . As a outcome of this change, the beta polypeptide chains convert sticky in low oxygen circumstances since the valine sticks out of the chain and interrelates with neighboring non-polar amino acids.
Radiation can actually affect the entire body, however it has a large effect of the bone marrow. Radiation is dangerous because too much can cause cellular depredation, this happens in environment that rapidly change like the bone marrow, which then interferes with blood cell production.
Interphase: Chromosomes duplicate, and the copies remain attached to each other.
Prophase: In the nucleus, chromosomes condense and become visible. Spindle fibers begin to form.
Prometaphase: The nulcear membrane breaks apart, and the spindle starts to interact with the chromosomes.
Metaphase: The copied chromosomes align in the middle of the spindle.
Anaphase: Chromosomes separate into two genetically identical groups and move to opposite ends of the spindle.
Telophase: Nuclear membranes form around each of the two sets of chromosomes, they begin to spread out, and the spindle begins to break down.
Cytokinesis: The two cells split into two daughter cells, each with the same number of chromosomes as the parent cell.
Answer:
A
Explanation:
Based on the word choice and structure of the sentence, A gives off the most positive connotation upon reading out of all of your choices.
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