Answer:
<em><u>The correct option is A) carbohydrate chain</u></em>
Explanation:
The carbohydrate chain present in the cell membrane helps determine the characteristics of the cell and it also helps to identify the chemical signals from outside the cell. Hence, option A is correct.
Other options, like option B, is not correct because the function of the cholesterol in the cell membrane is to prevent the fatty acids from sticking together. Option D is not correct because transport proteins help some molecules to move inside the cell.
Blood enters the pulmonary vein with close to 100% of the blinding site for oxygen saturated.
Respiration
Hope this helps :)
