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>
I think it's number 3 .......
Isobars represent adjusted atmospheric pressure. This removes pressure discrepancies caused by the location's relation to sea level or altitude. Isobars are also adjusted when necessary so that they never cross or touch. Weather maps with isobars give pressure information at a glance. They also give an approximation of wind direction because wind moves from high-pressure areas to low-pressure areas as large air masses move through the pressure differential.
Food preparation is the process that involves planning and preparing of meals. The food prep (preparation) list is a sheet that contains information of ingredients and the amount of each of the ingredients required when preparing a particular dish. The food prep list is part of a recipe which makes the kitchen much more organized and prevents wastage and excessive use of ingredients.
