Answer:
The two main reasons are nonpolar core of the bilayer and the active transport.
Explanation:
The membrane is structured to have two outer layers that are polar and an inner layer that is nonpolar.
If a membrane protein is exposed to the solvent, i<em>t will also have a polar side. It would be very difficult for the polar face of the membrane to move through the nonpolar core of the bilayer.</em> Therefore, this model is not feasible.
One major form of transport, active transport, moves solutes up the concentration gradient. <em>The binding of a solute and then release on another side of the membrane would only work for facilitated diffusion because it would cause a net movement of solutes down the concentration gradient.</em> It is unclear how energy could be expended to drive this process in the transverse carrier model.<em> Therefore, the transverse carrier model does not explain active transport.</em>
1 the atmosphere because gas is everywhere.
The blood group of AB because they are have both A and B glycoproteins on the surface of the cell
A balance that performs in an enclosed compartment with no air currents to disturb is called an analytical balance.
Analytical balances are instruments used for precise and determination of mass of matter. They are accurate and very precise instruments. They require a draft-free location on a solid bench that is free of vibrations.
Analytical balances of today are digital and have built in calibration weights to maintain accuracy. Older versions usually require to be manually calibrated using specific standard weights.
