Answer:
A: Oxygen levels are low and, therefore, more red blood cells are produced, giving the athletes an advantage when competing at lower altitudes.
Explanation:
<em>At high altitudes, the partial pressure of oxygen is lower compared to lower altitudes</em>. The body system try to adjust to lower oxygen level by undergoing several physiological changes. Depending on the duration spent in high altitude, the body can either try to adjust in the short term or acclimatize for a longer term.
One of the processes the body undergoes during acclimatization is an increase in red blood cell production. The kidney secretes erythropotein in response to inadequate oxygen in body tissues, and this makes the liver to increase erythrocyte production.
The increase in red blood cell production correspondingly increases the oxygen-carrying capacity of the blood as a result of increased hemoglobin. This condition persists for a few weeks even after the body returns to lower altitude where oxygen is adequate. Increased oxygen capacity means the rate of energy production (through respiration) within the body will also increase
<em>Hence, those who acclimatize to high altitude usually experience increased capillary density, tissue perfusion and improved athletic performance at lower altitudes. </em>
The correct option is A.
Here's the excerpt.
Guppies are small, tropical freshwater fish that display wide variation in coloration. Some have bright splotches of blue, red, and orange, while others are quite drab and dull. Research has shown that females prefer to mate with brightly colored males; however, this trait makes them more likely to be seen. Guppies, like all species, must be able to both sur<span>vive and reproduce in order to avoid extinction
One process that is responsible for the variations in coloration observed in guppies is that how females mate with male guppies. They prefer to mate with brightly colored males.</span>
Answer:
Nuclear import:
1. GTP hydrolysis is known to be required for the translocation process
2. The pore complex consists of more than two dozen proteins and is large enough to be readily seen through electron microscopy
Mitochondrial import:
1. ATP hydrolysis is known to be required for the translocation process
2. The signal sequence is always at the polypeptide's N-terminus and is cut off by a peptidase inside the organelle
3. There is strong evidence for the involvement of chaperones during the translocation process
4. The signal sequence is recognized and bound by a receptor protein in the organelles outer membrane
Both:
1. The polypeptide to be transferred into the organelle has a specific short stretch of amino acids that targets the polypeptide to the organelle
2. The imported protein enters the organelle through some sort of protein pore
Explanation:
Answer;
5,000 amino acids.
Explanations;
Amino acids are the basic building blocks of proteins; contains a carboxyl group (-COOH) and an amino group (-NH2).
Proteins are large, complex organic molecules consisting of a large number of amino acids linked together by peptide bonds.
A protein may consist of as many as 5, 000amino acids.
