Answer:
The nucleus at the central part of the cheek cell contains DNA. When a drop of methylene blue is introduced, the nucleus is stained, which makes it stand out and be clearly seen under the microscope.
Copied
Answer:
Explanation: The cell wall surrounds the plasma membrane of plant cells and provides tensile strength and protection against mechanical and osmotic stress. It also allows cells to develop turgor pressure, which is the pressure of the cell contents against the cell wall.
Answer:
a dominant mutation
Explanation:
A monohybrid testcross is a cross-breeding experiment used to determine if an individual exhibiting a dominant phenotype is homo-zygous dominant or heterozygous for a particular phenotypic trait (in this case, wing length). In a monohybrid testcross, a 1:1 phenotypic ratio shows that the dominant parental phenotype was a heterozygote for a single gene that has complete dominance. Moreover, a 3:1 ratio in the F2 is expected of a cross between heterozygous F1 individuals, which means that 75% of individuals with short wings have the dominant allele that masks the expression of the long-wing trait (i.e. the recessive allele).
Answer:A.) True
Explanation:
E.Coli would be a good model organism to study how the cell membrane controls movement of substances in and out of cells because it a eubacteria .Eubacteria characteristics include the ability to allow the movement of molecules across its membrane once a proton gradient is established , The membrane also has permeability enhancing properties that allow for the easy movement of substances.
We require to keep our water supply clean because we imbibe that water. If our water supply wasn't unsullied, we would die of dehydration. Another reason is that without water, all the crops would die and we wouldn't have any aliment to victual and so we would withal die of hunger.