本题目来源于试卷: Form and Function B.1 Carbohydrates & Lipids，类别为 IB生物学
[单选题]
Which of the following is only able to trigger a recak);qhy)8++gmz 7m hgast0 nsponse i,5 z bz )ob lzmk8k;2yutf8,xd(lc (yln a cell by binding to a receptor in the plasma membrzf ;m8by 8 k)5ylzdzl,ux, (ocl(btk2ane?
A. Insulin
B. Testosterone
C. Oestradiol
D. Progesterone
参考答案: A
本题详细解析:
Choice A is correc 8t u90j7 tqp .;ipfqkma5sr2lt because insulin is a peptide hormone, which is polar so cannot directly pass through the plasma membrane. Instead it binds to receptors in the plasma membrane which triggu;.92 j tqsl t7kif5q8mrpa p0ers intracellular signalling pathways.Choices B, C and D are all incorrect, as they are all non-polar steroids so can diffuse through the plasma membrane and bind directly to receptors inside the cell, affecting gene expression.
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