【单选题】Which kind of unemployment results from a change in the basic composition of the economy that also opens new positions for trained workers?______.
【单选题】Which of the following statements about the lipid composition of plasma membrane is wrong?
A.
Cholesterol is prominent in plasma membranes but barely detectable in mitochondrial membranes. Cardiolipin is a major component of the inner mitochondrial membrane but not of the plasma membrane.
B.
Phosphatidylserine, phosphatidylinositol, and phosphatidylglycerol are relatively minor components of most membranes but serve critical functions; phosphatidylinositol and its derivatives, for example, are important in signal transductions triggered by hormones.
C.
Sphingolipids, phosphatidylcholine, and phosphatidylethanolamine are present in most membranes but in varying proportions.
D.
Glycolipids, which are major components of the chloroplast membranes of plants, are also found in animal cells.