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question 25
which of the following is not true of the outer membrane?
a the uppermost layer is made of lipopolysaccharide.
b the lipid portion of the lipopolysaccharide layer is termedendotoxin.
c the innermost layer is a phospholipid bilayer.
d gram - positive bacteria have an outer membrane.
e porins create channels through the outer membrane.

Explanation:

Gram - positive bacteria have a thick peptidoglycan layer but lack an outer membrane. Gram - negative bacteria have an outer membrane. Options A, B, C, and E are correct facts about the outer membrane. The outermost layer of the outer membrane of gram - negative bacteria is lipopolysaccharide, the lipid part of lipopolysaccharide is endotoxin, the innermost layer is a phospholipid bilayer, and porins form channels in the outer membrane.

Answer:

D. Gram - positive bacteria have an outer membrane.