Answer: <u>Unwind
</u>
Explanation: Transcription is a process where a DNA strand is used to make a copy of mRNA. A complementary mRNA strand is made from the DNA strand. This mRNA is then later used to make proteins. In this process the junk information, present in DNA in form of introns is also spliced.
DNA is a double stranded structure, which is present in helical structure and both the strands are twisted together. In order to make the mRNA copy with the help of the enzyme RNA polymerase, DNA must open up. Then only RNA polymerase will be able to access the nucleotides of DNA.
Answer:
Vor 416 bis 360 Millionen Jahren
Wurzeln waren eine frühe Entwicklung im Pflanzenleben und entwickelten sich an Land während der Devon-Zeit vor 416 bis 360 Millionen Jahren (Gensel et al., 2001; Raven und Edwards, 2001; Boyce, 2005; Kenrick, 2013).
Explanation:
Entschuldigung, wenn das nicht geholfen hat
Answer:
E) Improve membrane fluidity
Explanation:
Cholesterol constitutes the basic structural element of the skeleton of cell membranes. Without their reinforcement, the membranes would become extremely fluid and lose their consistency. Cholesterol is found in the esterified membranes in its hydroxyl group (OH): with fatty acids, mainly oleic and linoleic, or as cholesterol sulfate. The cholesterol-sulfate polar group is disposed on one of the faces of the membrane that interacts with other polar groups in that area, while its bulky hydrophobic portion is embedded between the apolar parts of the lipids that form the membrane skeleton and They fulfill many other functions, among which the reduction in the permeability of protons and sodium ions, and their participation in signal transmission. Cholesterol is also essential in phagocytosis processes carried out by cells to capture many nutrients and, in general, for the function of cleaning up organic waste produced by macrophages.
The membranes must have a fluid structure so that the integrated proteins can move "horizontally" to interact with their ligands and with other proteins. The fluidity is given by unsaturated fat. With the excess of saturated fat, the membranes become rigid, but only with the necessary unsaturated fat the membranes are extremely fluid and very sensitive to temperature changes. Cholesterol stabilizes the structure of the membranes; In order for them to have the correct structure, they must have the correct proportions of saturated, unsaturated fats and cholesterol. The membranes produced in the laboratory without cholesterol are unstable to temperature changes, drastically modifying their fluidity against the small temperature changes that occur in the physiological range.
In addition to its functions in cell membranes, cholesterol is an important product that metabolism uses as a raw material to make other compounds:
*Bile salts
*Sex hormones
*Hormones of the adrenal cortex (corticosteroids)
*Vitamin D (Calciferol)
Simple Diffusion Across the Cell (Plasma) Membrane. The structure of the lipid bi-layer allows small, uncharged substances such as oxygen and carbon dioxide, and hydrophobic molecules such as lipids, to pass through the cell membrane, down their concentration gradient, by simple diffusion.
