14 Cell membranes are made up mainly of proteins and carbohydrates. How do these
molecules function in the cell membrane?

The cell membranes consist of a lipid bilayer (a double layer of lipids) in which various proteins are immersed, these act as pores through which certain substances can enter or leave the cell. The carbohydrate content of the plasma membrane varies between 2 and 10% of its weight, they support the cell membrane by adhering to it

Explanation:

The lipid bilayer has been established as the universal basis for the structure of the cell membrane. Membrane proteins have both structural and enzymatic functions; ferritin is a protein that transports and, at the same time, stores iron; myosin is involved in muscle contraction, but it also functions as an enzyme capable of hydrolyzing ATP, and so many more examples could be given.In living beings, transport phenomena are essential, either to carry a hydrophobic molecule through a aqueous medium (transport of oxygen or lipids through the blood) or to transport polar molecules through hydrophobic barriers (transport through the plasma membrane). Biological transporters are always proteins. The carbohydrate part (biomolecules composed of carbon, hydrogen and oxygen, whose function is to provide immediate and structural energy) of the molecule is always on the outside of the cell. Some proteins form water-filled channels through which polar or electrically charged substances can pass that do not pass through the phospholipid layer.

the act of deciding on matters of the economy. economic decision making is routinely conducted by finance ministers, economic advisors, heads of major central banks and business leaders and can have profound effects on a major economy.

the correct answer is modern american cars are not available due to trade restrictions.

trade between cuba and the united states have serious restrictions. the u.s. imposed an economic embargo on cuba, that among other things means that modern american cars are not available due to trade restrictions.

in response to some governmental actions of the authorities from cuba, president john f. kennedy proclaimed an embargo on trade between both countries in february 1962. the trade embargo remains active until this day and was implemented directly by the departments of commerce and the department of treasury.

in president trump’s administration, there is a national security presidential memorandum that "strengthens the policy of the u. s.", affecting trade with cuba.