【单选题】A transport layer protocol has several responsibilities, One is to create a process-to-process (program-to-program) communication; TCP uses port (1) to accomplish this. Another responsibility of a tra...
【多选题】How do intermediate filaments strengthen cells against mechanical stress?
A.
Intermediate filaments are particularly prominent in the cytoplasm of cells that are subject to mechanical stress.
B.
They are present in large numbers, for example, along the length of nerve cell axons, providing essential internal reinforcement to these extremely long and fine cell extensions.
C.
They are also abundant in muscle cells and in epithelial cells such as those of the skin. In all these cells, intermediate filaments distribute the effects of locally applied forces, thereby keeping cells and their membranes from tearing in response to mechanical shear.
D.
A similar principle is used to strengthen composite materials such as fiberglass or reinforced concrete, in which tension-bearing linear elements such as carbon fibers (in fiberglass) or steel bars (in concrete) are embedded in a space-filling matrix to give the material strength.