本题目来源于试卷: Form and Function B.3 Membranes & Membrane Transport，类别为 IB生物学
[单选题]
Which statement correct2 d6eu ;66 a zvbyuj2gm8p grvwfbf+),fz:dm1 up v-zax 3kn1*ly describes the cell membrane structure?
A. A phospholipid bilayer where phosphate heads align facing each other and lipid tails point away.
B. A phospholipid bilayer where lipid tails align facing each other and phosphate heads point away.
C. A phospholipid bilayer where proteins line the outer layer and phospholipids line the inner layer.
D. A layer of phospholipids with phosphate heads facing outside the cell and lipid tails facing the cell cytoplasm.
参考答案: B
本题详细解析:
A cell membrane is formed of two loei(zoq eiz) a6cn3/0ct,y iyq1v 2x:ayers of phospholipids whereby hydrophilic phosphate heads face the cytoplasm of the cell (cell interior) and the cell's environment (exterior) while the hydrophobic lipid tails face each other and form the interior of the membrane.Having lipid tails pointing away (Choice A) is not a valid choice since lipid tails are hydrophobic and cannot face the cell's aqueous interior and exterior. Proteins are embedded in the membrane and do not line the outer layer (Choice C). The cell memb q( e,6c21ia)o/:ix czintqyyze30ov rane is a bilayer and not just a monolayer (Choice D).
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