Answer:
This difference indicates that the results are precise but not accurate
.
Explanation:
Precise results are those that are very close to the actual result, but do not achieve exactly the same result. In addition, this difference between the precise results is exactly the same. We have an example of this in the case shown in the figure above, where the blood pressure readings measured by the cuff differ by 15 points for each reading. This case also shows us that the results are not accurate, because this type of result is one that shows a result exactly the same as the real one.
in the earth's atmosphere is made up about approximately 78 percent nitrogen and 21 percent oxygen.
<span>Cytotoxic t-cell subpopulations are specialized to combat intracellular pathogens, whereas helper t-cell subpopulations are specialized to combat extracellular pathogens.
</span>Cytotoxic t-cell are CD8+ cells. Cytotoxic t-cell uses granzymes to <span>kill </span><span>intracellular bacteria, that lives in the cytosol such as viruses. They identify the pathogen forgein peptids that are bounded to MHC-I on the cell surface.
</span>
cd4+ T helper (Th) cells include Th1, Th2, and Th17 cells. They contribute to aliergic reactions and fighting extracellular parasites.
Answer:
B) There is an increase in the number of giraffes with long necks in areas of Africa where low-growing trees have died
Explanation:
The directional selection is one of the ways of the natural selection in which the natural selection selects or favours the most extreme trait of the species and the extreme trait show higher fitness than the normal or average trait.
In the given question, the case of Giraffe necks shows directional selection as the normal length of the neck is not favoured by the environment but the extreme trait that is long neck is favoured by the environment and the selection shifted to that level.
Thus, Option-B is the correct answer.
Answer:
The correct answer is: Hydrophobic, Hydrophobic.
Explanation:
- Proteins are made up of polypeptide chains which are formed by the polymerization of amino acid molecules, linked together by peptide bonds.
- The amino acids can be broadly classified into non-polar and polar.
- The non-polar amino acids can be defined as those amino acids whose side chains possess hydrocarbon molecules only. They do not possess any charge and are incapable of forming hydrogen bonds with water molecules. They tend to avoid water and so they tend to remain buried into the interior of a protein. Examples can be illustrated as Leucine, Valine, Isoleucine, Phenylalanine, etc.
- The polar amino acids can be defined as those amino acids whose side chains either possess a charge (positive or negative) or a hydroxyl group which is capable of forming hydrogen bonds with water molecules. As they tend to form hydrogen bonds with water molecules they are usually found on the surface of the proteins. Examples can be illustrated as Lysine, Arginine, Serine, Asparagine, etc.
