【单选题】Most molecules and all ions require a process to across cellular membranes. The process is mediated by selective ( ).
A.
membrane transport proteins
C.
peripheral membrane proteins
D.
lipid-anchored membrane proteins
【单选题】AutoCAD2008图形文件和样板文件的扩展名分别是:
【单选题】Crossing a membrane by simple diffusion can be distinguished from facilitated diffusion because:
A.
Simple diffusion does not require energy: facilitated diffusion requires a source of ATP.
B.
Simple diffusion can only move material in the direction of a concentration gradient; facilitated diffusion moves materials with and against a concentration gradient.
C.
Simple diffusion is not saturable; facilitated diffusion rates are limited by the number of functional membrane proteins and can be saturated
D.
Simple diffusion is found only in prokaryotes while facilitated diffusion is found only in eukaryotes.
【判断题】可对膜(membran)单元可以用集中载荷
【单选题】According to the passage, which of the following is important in explaining a muscle movement()
A.
The flow of blood to the muscles.
B.
Classical conditioning.
D.
The entry of unpleasant stimuli through the cell membran
【单选题】根据软硬酸碱原理,判断下列各组配合物的标准生成常数 K 稳 相对大小,正确的是
A.
K 稳 (FeF 4- ) < K 稳 (FeCl 4- )
B.
K 稳 (Ag(CN) 2 - ) > K 稳 ( Ag(NH 3 ) 2 + )
C.
K 稳 (CoF 6 3 - ) < K 稳 (CoF 6 4 - )
D.
K 稳 (HgCl 4 2 - ) > K 稳 (HgI 4 2 - )
【单选题】AutoCAD 2008的图形文件和样板文件的扩展名分别是()
【单选题】Solutions A and B are separated by a semipermeable membrane that is permeable to K + , but not to Cl - . Solution A is 100 mM KCl, and solution B is 1 mM KCl. Which of the following statements about s...
A.
K + ions will diffuse from solution A to solution B until the [K + ] of both solutions is 50.5 mM
B.
K + ions will diffuse from solution B to solution A until the [K + ] of both solutions is 50.5 mM
C.
KCl will diffuse from solution A to solution B until the [KCl] of both solutions is 50.5 mM
D.
K + will diffuse from solution A to solution B until a membrane potential develops with solution A negative with respect to solution B
E.
K + will diffuse from solution A to solution B until a membrane potential develops with solution A positive with respect to solution B