Answer:
b. a semi-permeable double layer of phospholipids that have hydrophilic heads and hydrophobic tails
Explanation:
B is correct as the cell membrane is selectively semi-permeable. It is selectively semi-permeable because this quality allows it to control what can and can't enter the cell, and how it does so.
The cell membrane also has a phospholipid bi-layer comprised of a double layer of phospholipids which have hydrophilic head and hydrophobic tails. This is because the heads are made of phosphate and are polar and are therefore attracted to water (hydrophilic), while the tails are made of lipids (i.e. fats, oils) which do not mix with water and are therefore hydrophobic.
The properties of each phospholipid is also why they form the double layer structure, the hydrophilic heads naturally face outwards into the water and protect the hydrophobic tails on the inside.
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Exercise is the primary advice the coaches give to the athletes if they get a cold or any other infection. The main reason behind this advice is the fact that exercising strengthens the immunity of a person. When a person has an infection, the strengthening of the immune system will help his body to efficiently fight against the infectious pathogens. The blood circulation is increased which is involved in the enhancement of the acute immunity of the person.
Answer:
Follows are the solution to this question:
Explanation:
The following are the two considerations demonstrating that there would be less biodiversity than the tropical areas in the Mediterranean climate as well as polar areas.
- The first reason is all tropical areas experience drastic temperature variation.
- The second reason is early in the earth's history, the northern latitudes are inhabited.
The three large arteries originating from the aortic arch are the brachiocephalic trunk<span>, left </span>common carotid artery<span>, and left </span>subclavian artery<span>.</span>
