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Which one of the following molecule is amphipathic, with both a hydrophilic and hydrophobic region?

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Correct Answer: B. Phospholipids
The cell membrane is composed of a phospholipid bilayer that has a hydrophilic head (where the polar phosphate is attached) and a hydrophobic tail (made up of hydrocarbon chains). Starch is a polysaccharide that is generally hydrophilic and can be dissolved in water. Triglycerides, steroids and cholesterol are all entirely hydrophobic not being able to be dissolved in water. The molecule mentioned in the question is both hydrophilic and hydrophobic, indicative of the phospholipid, therefore only answer option [B] is correct.
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