20 notecards = 5 pages (4 cards per page)
The fluidity of the lipid side chains in the interior of a bilayer is generally increased by a decrease in temperature
Which of these statements about the composition of biological membranes is false?
A) In a given eukaryotic cell type (for example, a hepatocyte), all intracellular membranes have essentially the same complement of lipids and proteins.
The type of motion least common in biological membranes is:
A) flip-flop diffusion of phospholipid from one monolayer to the other.
Which of these statements is generally true of integral membrane proteins?
A) A hydropathy plot reveals one or more regions with a high hydropathy index.
The inner (plasma) membrane of E. coli is about 75% lipid and 25% protein by weight. Approximately how many molecules of membrane lipid are there for each molecule of protein? (Assume that the average protein is Mr 50,000 and the average lipid is 750.)
A hydropathy plot is used to:
E) predict whether a given protein sequence contains membrane-spanning segments.
The shortest α helix segment in a protein that will span a membrane bilayer has about _____ amino acid residues.(This is another critical thinking question. Hint: Look at the figure describing a turn in an alpha helix. Find the length of a lipid bilayer)
Which one of the following statements about membranes is true?
C) Sterol lipids are common in human cell plasma membranes.
When a bacterium such as E. coli is shifted from a warmer growth temperature to a cooler growth temperature, it compensates by putting more unsaturated fatty acids into its membranes.
E) have all of the properties listed above.
Which of the fatty acids has the higher melting temperature?
Which of the following is not a fat-soluble vitamin?
Which of the following statements is true of lipids?
B) Most are simply polymers of isoprene.
Lipids are large polymers
Fatty acids are strongly hydrophilic
Sterols are found in the membranes of all living cells.
All other things being equal the more unsaturation, the lower the melting temperature
All other things being equal, the longer the acyl chain, the higher the melting temperature
Which of the following molecules or substances contain, or are derived from, fatty acids?
E) All of the above contain or are derived from fatty acids.
Which of the following best describes the cholesterol molecule?