1. The gecko is a reptile with an amazing ability to climb smooth surfaces, including glass. Recent discoveries indicate that geckos stick to smooth surfaces via van der Waals interactions between septae on their feet and the smooth surface.How is this method of stickiness advantageous over covalent interactions? Given that van der Waals forces are among the weakest molecular interactions, how can the gecko’s feet stick so effectively?
1、壁虎是一种具有了不起的攀爬能力的爬行动物，即使是光滑的表面,包括玻璃。最近的发现表明,壁虎坚持光滑的表面通过范德瓦耳斯相互作用其间有脚和光滑表面之间。这种方法的粘性有利于共价相互作用吗?鉴于范德瓦尔斯力最弱的分子相互作用,如何壁虎的脚贴这么有效?
2. The K channel is an example of a transmembrane protein (a protein that spans the phospholipid bilayer of the plasma membrane). What types of amino acids are likely to be found (a) lining the channel through which K_ passes;(b) in contact with the phospholipid bilayer containing fatty acid; (c) in the cytosolic domain of the protein; and (d) in the extracellular domain of the protein?
2、钾通道是一个横跨膜的蛋白质(蛋白质的跨膜磷脂双分子层的等离子体)。什么类型的氨基酸
可能会发现K传递的渠道与磷脂双分子层含有脂肪酸的细胞质域蛋白在细胞外蛋白质域有衬套?
3. V-M-Y-Y-E-N: This is the single-letter amino acid abbreviation for a peptide. Draw the structure of this peptide. What is the net charge of this peptide at pH 7.0? An enzyme called a protein tyrosine kinase can attach phosphates to the hydroxyl groups of tyrosine. What is the net charge of the peptide at pH 7.0 after it has been phosphorylated by a tyrosine kinase? What is the likely source of phosphate utilized by the kinase for this reaction?
3、V-M-Y-Y-E-N:这是单肽氨基酸缩写。画出这个肽的结构。这种肽的净电荷是在pH值7.0 吗?一个称为蛋白质酪氨酸激酶的酶可以将磷酸盐附加到酪氨酸的羟基。肽的净电荷在pH值7.0由酪氨酸激酶磷酸化后?什么是可能的磷酸源利用的激酶反应?
4. Disulfide bonds help to stabilize the three-dimensional structure of proteins. What amino acids are involved in the formation of disulfide bonds? Does the formation of a disulfide bond increase or decrease entropy (S)?
reaction between pvp and amino
4、二硫键有助于稳定蛋白质的三维结构。包含哪些氨基酸的形成二硫键?二硫键的形成是增加还是减少了熵(S)?
5. In the 1960s, the drug thalidomide was prescribed to pregnant women to treat morning sickness. However, thalidomide caused severe limb defects in the children of some women who took the drug, and its use for morning sickness was discontinued. It is now known that thalidomide was administered as a mixture of two stereoisomeric compounds,one of which relieved morning sickness and the other of which was responsible for the birth defects. What are stereoisomers? Why might two such closely related compounds have such different physiologic effects?
5、在1960年代,该药物萨力多胺是规定孕妇晨吐。然而,萨力多胺造成了严重肢体缺陷的孩子一些服用该药物的女性,早上和它的使用疾病被中断。现在知道萨力多胺是管理两个立体异构的化合物的混合物,其中一个是缓解晨吐的,另一个是负责出生缺陷的。立体异构体是什么呢?为什么这两个密切相关的化合物有这样不同的生理作用?
6. Name the compound shown below. Is this nucleotide a
component of DNA, RNA, or both? Name one other function
of this compound.
6、如下所示的化合物名称。这是核苷酸组件的DNA,RNA,或者都有? 命名这种化合物的另一个函数。
7. The chemical basis of blood-group specificity resides in the carbohydrates displayed on the surface of red blood cells.Carbohydrates have the potential for great structural diversity.Indeed, the structural complexity of the oligosaccharides that can be formed from four sugars is greater than that for oligopeptides from four amino acids. What properties of carbohydrates make this great structural diversity possible?
7、血型特异性驻留在碳水化合物的化学基础上显示红细胞的表面。碳水化合物有潜在的巨大结构多样性。事实上,低聚糖的结构复杂性,可以由四个寡肽糖从四个氨基酸构成。什么属性的碳水化合物使这个伟大的结构多样性变成可能呢?
8. Ammonia (NH3) is a weak base that under acidic conditions becomes protonated to the
ammonium ion in the following reaction:
NH3+H+---NH4+
NH3 freely permeates biological membranes, including those of lysosomes. The lysosome is a subcellular organelle with a pH of about 5.0; the pH of cytoplasm is 7.0. What is the effect on the pH of the fluid content of lysosomes when cells are exposed to ammonia? Note: Protonated ammonia does not diffuse freely across membranes.
8、氨(NH3)是一种弱碱,在酸性条件下成为质子化的铵离子的反应如下:
NH3+H+---NH4+
NH3自由渗透到生物膜,包括溶酶体。溶酶体是一个亚细胞的细胞器，pH值约为5.0，细胞质的pH值是7.0。当细胞暴露于氨中时有什么影响流体溶酶体内pH值吗?注意:跨膜质子化了的氨不会自由扩散。
9. Consider the binding reaction L+R--- LR, where L is a ligand and R is its receptor. When
0.001 ML is added to a solution containing 0.05 MR, 90% of the L binds to form LR. What is the Keq of this reaction? How will the Keq be affected by the addition of a protein that catalyzes this
binding reaction? What is the Kd?
9、考虑L + R结合反应生成LR,R是一个配体、L是一个受体。当0.001 ML被添加到能够容纳0.05MR反应容器中时,90%的L合成后生成 LR。在这个反应中Keq是什么? Keq将如何受蛋白质催化这个捆绑的反应?Kd是什么呢？
10. What is the ionization state of phosphoric acid in the cytoplasm? Why is phosphoric acid such a physiologically important compound?
10、什么是细胞质磷酸的电离状态？为什么磷酸在生理学上是如此重要的化合物？
11. The ∆G0  for the  reaction X+Y--XY is -1000cal/mol. What is the ∆G0 at 25C (298 Kelvin) starting with 0.01 M each X, Y, and XY? Suggest two ways one could make this reaction energetically favorable.

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