Answer:
The monomers combine with each other by covalent bonds to form larger molecules known as polymers.
Explanation:
Heat transfer means heat energy is transferred from on object or a body to another. This causes change in many factors, and temperature is one of such factors. If the temperature increases, it means heating is taking place and if temperature decreases it means cooling is taking place.
If Tfinal is more than Tinitial, it means the object has gained some amount of heat energy. Therefore, heating is taking place.
If Tfinal is less that Tinitial, it means the object has lost some heat energy and cooling is taking place.
Answer:
pulmonary vein
Explanation:
The pulmonary veins
transfer oxygenated blood from the lungs to the heart.
It helps complete the pulmonary circuit, by receiving oxygenated blood in the alveoli and returning it to the left atrium.
They are like that because they can't always be faulty and may have at least some spark of truth to this theory also as stated earlier a theory in scientific terms is just an observation so it can't really be turned down hence theory.
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)
