completed question'
.....culturing viruses that requires a human host
Answer:
Diploid cell culture lines, developed from human embryos, are widely used for culturing viruses that require a human host
Explanation
Viruses can not thrive in a non-living host or artificial media.They are intracelular parasites which needed living host to replicate . Cultures lines from Human embryo in are therefore used for culturing viruses of human host, so that its mode of replication and gene expression can be studied, and therefore its virulence can easily be studied.
This method have the advantage that;
1.there is no need to make use of the whole animal rather,on a tiny tissue needed can be isolated for culture.
2. the cells growth is continuous,and can be preserved in liquid Nitrogen and renew for future culture
3. cells can be grown in different containers, with ability to decide the number of cells needed.
Temperature is kept at optimum for human in the culture at 37 degree centigrade, nutrients are provided, NaHC03 as buffers for C02, and the medium is humidified.
<h2>
<u>EARTH'S MAGNETIC FIELD</u></h2>
The magnets point North when the Earth's magnetic field has?
<h2>
<u>ANSWER</u></h2>
I think the best answer for this question is Magnetic Reversal or Geomagnetic Reversal.
In geomagnetism, the term "geomagnetic reversal" also known as 'flip', is the process by which the North pole becomes South pole and the South pole transforms into North pole.
<h2>
<u>THE MAGNETIC REVERSAL</u></h2>
The reversals happen on rare occasions when iron molecules start moving towards the opposite direction as other iron molecules around them within the Earth's spinning outer core.
Water then moves from cell to cell through the root cortex by osmosisalong a concentration gradient; this means that each cell is hypertonic to the one before it. In the centre of the root the water enters the xylem vessels. Water may move by diffusionthrough the cell walls and intercellular spaces.
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)
Answer:
It was a multi celled organism
Explanation: