在结晶肽的X-射线研究中,LinusPauling和Robertcorey发现肽链中的肽键(C-N)长度(1.32A)介于典型的C-N单键(1.49A)和C=N双键(1.27A)之间。他们也发现肽键呈平面状(与肽键相连接的4个原子位于同一个平面)以及两个碳原子彼此呈反式(位于肽键的两侧)与肽键连接。 (a)肽键的长度与它的键的强度和键级(是单键、双键或三键)有什么关系? (b)从Pauling等人的观察,就肽键旋转能得出什么看法?
信号肽(signal peptide)
肽(peptides)
与可转换债券(Convertible Bond)相比,可交换债券(Exchangable Bond)最显著的特征是()。
肽单位(peptide unit)
A consol bond is a bond that _________
A coupon bond pays the owner of the bond _________
(I) Callable bonds must have a higher yield than comparable noncallable bonds. (II) Convertible bonds are attractive to bondholders and sell for a higher price than comparable nonconvertible bonds.
Most municipal bonds are revenue bonds rather than general obligation bonds.
The current yield on a coupon bond is the bond's _________ divided by its _________
When the quantity of bonds demanded equals the quantity of bonds supplied there is ________
intestinal cells absorb aa and peptides. these cells finish splitting peptides into individual aa.
Corporate bonds are less risky if they are _________ bonds and municipal bonds are less risky if they are _________ bonds.
When a municipal bond is given tax - free status, the demand for municipal bonds shifts _________, causing the interest rate on the bond to _________
A semi-annualcorporate bond has a face value of $1,000, a yield to maturity of 6.9 percent,and a coupon rate of 6.5 percent.The bond matures 8 years from today. This bond:
Suppose you hold a 1 year annual coupon bond sold by the U.S. government. The bond has a face value of $100, the coupon rate is 5%, and the current yield in the market for this type of bond is also 5%. What is the bond worth?
Prices for long - term bonds are more volatile than for shorter - term bonds.
由于肽键所连接的六个原子处于同一平面上,所以肽键不能自由旋转。()此题为判断题(对,错)。
脑-肠肽(brain-gut peptide)
Zero-coupon bonds differ from other bonds in having______.
下列关于肽键的描述中,哪一条是不正确的?()A.肽键是肽链上的-N-Cα-C-序列B.肽键是一种酰氨键
胰岛素分子的一级结构中除肽键外还有()。A.氢键B.肽键C.二硫键D.离子键E.疏水键
How does corporate bond differ from government bond.
The interest from Guam Water Authority bonds is excluded from income as "Municipal Bond Interest."()