Lecture 5 Lipids and cell membranes Chapter 11

Which membrane lipid is composed of sphingosine, fatty acid, and a simple sugar? a. sphingoside b. cerebroside c. sphingolipid d. sphingomyelin e. cardiolipin

Which lipids contain a branched chain of seven sugar residues? a. gangliosides b. sphingolipids c. glycolipid d. cerebrosides e. sugar-containing lipids

What is an alcohol component in cerebroside? a. glycerol b. ethanolamine c. inositol d. sphingosine e. choline

What is the common name of hexadecanoic acid? a. oleic acid b. stearic acid c. palmitic acid d. linoleic acid e. linolenic acid

What is the common name of (18:3) fatty acid? a. oleic acid b. stearic acid c. palmitic acid d. linoleic acid e. linolenic acid

The systematic name of linoleic acid is _____ acid. a. hexadecanoic b. octadecanoic c. octadecenoic d. octadecadienoic e. octadecatrienoic

What carbon atom from the carboxyl terminus of a fatty acid is often referred to as β? a. 1 b. 2 c. 3 d. 4 e. the last carbon atom in the chain

What lipids are referred to as polycyclic hydrocarbons? a. phospholipids b. steroids c. sphingolipids d. triacylglycerols with highly unsaturated fatty acids e. glycolipids

Choose the compound that is composed of a chain of hydrogen-bearing carbon atoms terminated with a carboxyl group. a. fatty acid b. triacylglycerol c. lipid d. carboxylic acid e. steroid

Choose the denotation for the double bond position and conformation in natural oleic acid. a. trans-Δ2 b. cis-Δ2 c. cis, cis-Δ9,Δ12 d. trans-Δ9 e. cis-Δ9

In what form does a fatty acid exist in the physiological pH range? a. anion b. cation c. protonated molecule d. acid e. zwitterion

The configuration of most fatty acids in biological systems is predominantly: a. cis. b. trans. c. all-trans. d. Δ12. e. ω-3.

A(n) _____ in the chain length will result in formation of _____ van der Waals interactions between the chains and a(n) _____ of the melting point. a. decrease; more; increase b. increase; more; increase c. increase; less; decrease d. decrease; more; decrease e. increase; less; increase

What linkages are in phosphoglycerides between fatty acids and a glycerol backbone? a. ether linkages b. thioether linkages c. phosphate linkages d. methylene linkages e. ester linkages

The common feature of all ω-3 fatty acids is/are: a. a methyl group at the carboxyl end of the fatty acid. b. a methyl group on the third carbon of the chain. c. a double bond between carbon atoms 2 and 3. d. a triple bond at the carboxyl end of the fatty acid. e. several double bonds in the chain.

What is a term for hydrophobic groups that are covalently attached to proteins and tether them to the membrane? a. lipid linkages b. membrane modifications c. membrane linkages d. membrane anchors e. membrane bonds

In proteins, the glycosylphosphatidylinositol anchor is attached to the: a. cysteine residue. b. cysteine residue at the carboxyl terminus. c. carboxyl terminus. d. amino terminus. e. serine residue.

A precursor to estradiol is: a. sitosterol. b. eicosapentaenoate. c. cholesterol. d. cardiolipin. e. arachidonate.

How many rings are in the steroid nucleus? a. 0 b. 1 c. 2 d. 3 e. 4

What group of living things contains in its cell membranes lipids with ether rather than ester linkages between the fatty acid chains and a glycerol backbone? a. fungi b. archaea c. bacteria d. mycoplasma e. eukaryotes

What is the main storage form of fatty acids? a. micelles b. liposomes c. triacylglycerols d. phospholipids e. glycolipids

What is the major site of accumulation of triacylglycerols in mammals? a. adipose tissue b. liver c. mitochondria d. endoplasmic reticulum e. insulating tissue

What are derived from the treatment of triacylglycerols with strong bases? a. salts of triacylglycerol b. diacylglycerols c. phosphatidic acids d. salts of fatty acids e. free glycerols

Which organisms do NOT have sterols in their membranes? a. bacteria b. fungi c. plants d. insects e. protozoa