Answer:
Professional gardeners often soak seeds in hydrogen peroxide before planting them in order to increase the germination percentage or to reduce germination failure. When the seeds are soaked in hydrogen peroxide, the seed coat becomes soft and enzymes present in the seed becomes active. Due to soaking of seeds, the seed takes less time to germinate. So that's why gardeners uses this method.
Answer: crossing over allows for genetic variation
Explanation:
crossing over is the exchange of genes between two chromosomes which ends up resulting in non-identical chromatids that comprise the genetic material of gametes (sperm and eggs).
Basically crossing over makes the chromatids that are held together by a centromere, no longer identical to eachother which creates genetic variation.
<span>The cytoplasm of the cell.</span>
The proteins exhibit four levels of organization:
1. Primary structure: It refers to a sequence of amino acids join together by the peptide bonds to produce a polypeptide chain.
2. Secondary structure: It is a localized twisting of the polypeptide chain by producing a hydrogen bond. Two types are formed, that is, the alpha helix and beta pleated sheet.
3. Tertiary structure: It refers to the three-dimensional composition of a polypeptide chain. The folding is not regular as it is in secondary composition. It produces ionic bonds, hydrophobic interactions, disulfide bond, and hydrogen bond amongst the polypeptide chains.
4. Quaternary structure: It comprises an amalgamation of two or more polypeptide chains that functions as a single functional unit. The bonds are identical as in tertiary composition.
Thus, the levels of secondary, tertiary, and quaternary protein structure would get affected if all the hydrogen bonding associations were inhibited.
The answer is D. In a
geological era, when the plants and animals
in the then environment die, they get buried
in sediments. These sediments are covered
by other sediments of another geological
time within which are the remains of dead species
of the then geological era. These sediments from different geological times have different properties hence
form visible strata that can be studied to identify the kind of environment in the then geological time. Their
fossils can also be studied to identify
the kind of species that roamed the earth during the time.
