Answer:
Endocardium
Explanation:
The endocardium makes the innermost lining of the wall of the heart. It is present over the thin layer of connective tissue. The function of the endocardium is to provide a smooth lining for the chambers of the heart. The valves present in the heart also have endocardium. The dense connective tissue of the heart valves is covered by endocardium.
The presence of the smooth endocardium made up of endothelium reduces the surface friction as blood passes through the heart. The endocardium of heart chambers is continuous with the endothelial lining of the large blood vessels that are attached to the heart.
Lactase refers to an enzyme that can dissociate lactose sugar into glucose and galactose. This enzyme plays an important role in the digestion of milk that comprises high lactose sugar. In case, if a mutation occurs in the gene codon of lactase, then two possibilities can take place. These are as follows:
1. Loss of mutation: In this case, the person becomes lactose intolerant because of mutation in lactase gene codon. Due to this, there is low mRNA expression and thus low production of the enzyme lactase. This is also known as lactase non-persistent phenotype.
2. Gain in mutation: In this case, the person gain an increase in mRNA expression of the lactase gene, thus more production of lactase takes place than usual. This kind of individual exhibits lactase persistent phenotype.
Answer:
Taxonomy- The science of naming and classifying organisms based on structural comparisons and genetic evidence.
Explanation:
Answer:
In this case, it is likely that the polypeptide chain assumed an alpha helix configuration because the lipid bilayer did not have beta-barrel proteins.
Explanation:
A polypeptide chain is naturally polar, however, a lipid bilayer is naturally non-polar. This makes it difficult and even prevents the polypeptide chain from crossing a lipid bilayer, since the composition of these two elements does not allow them to mix. In that case, the polypeptide chain has two options to take to successfully cross the lipid bilayer.
The first option that the polypeptide chain has is to allow the creation of twisted beta sheets in the shape of a closed barrel in its structure. This only works if the lipid bilayer has beta barrel proteins in its composition to act as a transport channel for the polypeptide chain. However, few lipid layers have this protein.
Most likely, the polypeptide chain assumes an alpha helix conformation to cross lipid bilayers that do not have beta-barrel proteins. By assuming the beta conformation, the polypeptide chain reinforces the hydrogen bonds present in its composition, allowing it to cross the lipid bilayer without having its conformation and structure disassembled.
Answer: It's known as the continental drift :)
Explanation: "Pangea's existence was first proposed in 1912 by German meteorologist Alfred Wegener as a part of his theory of continental drift. Its name is derived from the Greek pangaia, meaning “all the Earth.”" (copied from google)
