Lipids

Lipids are not soluble in water. Are lipids polar or nonpolar molecules?

Which of the following solvents might be used to dissolve an oil stain?

a. water

b. ${\mathrm{CCl}}_4$

c. diethyl ether

d. benzene

e. $\mathrm{NaCl}$ solution

What are some functions of lipids in the body?

What are some of the different kinds of lipids?

Describe some similarities and differences in the structures of a saturated fatty acid and an unsaturated fatty acid.

Stearic acid and linoleic acid each have 18 carbon atoms. Why does stearic acid melt at $69°\mathrm{C}$ but linoleic acid melts at $-5{}^{\circ }\mathrm{C}$ ?

Draw the line-angle formula for each of the following fatty acids:

a. palmitic acid

b. oleic acid

Draw the line-angle formula for each of the following fatty acids:

a. stearic acid

b. linoleic acid

For each of the following fatty acids, give the shorthand notation for the number of carbon atoms and double bonds, and classify as saturated, monounsaturated, or polyunsaturated:

a. linoleic acid

b. palmitic acid

c. myristic acid

d. oleic acid

How does the structure of a fatty acid with a cis double bond differ from the structure of a fatty acid with a trans double bond?

For each of the following fatty acids, give the shorthand notation for the number of carbon atoms and double bonds, and classify as saturated, monounsaturated, or polyunsaturated:

a. lauric acid

b. linolenic acid

c. palmitoleic acid

d. stearic acid

Compare the structures and functional groups of${\mathrm{PGF}}_1$ and ${\mathrm{PGF}}_2$ .

How does an anti-inflammatory drug reduce inflammation?

Draw the condensed structural formula for the ester in beeswax that is formed from myricyl alcohol,${\mathrm{CH}}_3-{\left({\mathrm{CH}}_2\right)}_{29}-\mathrm{OH}$,and palmitic acid.

What are some sources of omega- $3$ and omega- $6$-fatty acids (see Chemistry Link to Health "Omega-$3$ Fatty Acids in Fish Oils")?

What is the difference in the location of the first double bond in an omega-$3$ and an omega-$6$-fatty acid (see Chemistry Link to Health "Omega-$3$-Fatty Acids in Fish Oils")?

What are some effects of prostaglandins in the body?

How does the double bond influence the dispersion forces that can form between the hydrocarbon chains of fatty acids?

Compare the structures and functional groups of arachidonic acid and prostaglandin ${\mathrm{PGE}}_1$.

How does the percentage of monounsaturated and polyunsaturated fatty acids in sunflower oil compare to that of safflower oil?

Draw the condensed structural formula for the ester in jojoba wax that is formed from arachidic acid, a 20-carbon saturated fatty acid, and 1-docosanol, ${\mathrm{CH}}_3-{\left({\mathrm{CH}}_2\right)}_{21}-\mathrm{OH}$.

Draw the condensed structural formula for a triacylglycerol that contains stearic acid and glycerol.

Draw the condensed structural formula for a mixed triacylglycerol that contains two palmitic acid molecules and one oleic acid molecule on the center carbon of glycerol.

Safflower oil is polyunsaturated, whereas olive oil is monounsaturated. Why would safflower oil have a lower melting point than olive oil?

Linoleic acid is an $18$-carbon unsaturated fatty acid with two double bonds that occur in many vegetable oils including safflower oil $(75\%)$ and poppyseed oil $(75\%)$. Draw the line-angle formula for glyceryl trilinoleate (trilinolein).

Caprylic acid is an $8$-carbon saturated fatty acid that occurs in coconut oil $(10\%)$ and palm kernel oil $(4\%)$. Draw the line-angle formula for glyceryl tricaprylate (tricaprylin).

Olive oil is monounsaturated, whereas butter fat is saturated. Why does olive oil have a lower melting point than butter fat?

How does the percentage of monounsaturated and polyunsaturated fatty acids in olive oil compare to that of canola oil?

Olive oil is monounsaturated, whereas hutter fot is caturated. Why does olive oil have a lower meltiag point than butser far?

Identify each of the following processes as hydrogenation, hydrolysis, or saponification and give the products:

a. the reaction of palm oil with $KOH.$

b. the reaction of glyceryl trilinoleate from safflower oil with water and $HCl$.

Use condensed structural formulas to write the balanced chemical equation for the hydrogenation of glyceryl tripalmitoleate, a fat containing glycerol and three palmitoleic acid molecules.

Identify each of the following processes as hydrogenation, hydrolysis, or saponification and give the products:

a. the reaction of corn oil and hydrogen $\left({\mathrm{H}}_2\right)$ with a nickel catalyst

b. the reaction of glyceryl tristearate with water in the presence of lipase enzyme

Use condensed structural formulas to write the balanced chemical equation for the hydrogenation of glyceryl trilinoleate, a fat containing glycerol and three linolenic acid molecules.

Use line-angle formulas to write the balanced chemical equation for the acid hydrolysis of glyceryl trimyristate (trimyristin).

Use line-angle formulas to write the balanced chemical equation for the acid hydrolysis of glyceryl trioleate (triolein).

Use condensed structural formulas to write the balanced chemical equation for the $\mathrm{NaOH}$ saponification of glyceryl trimyristate (trimyristin).

Use condensed structural formulas to write the balanced chemical equation for the $\mathrm{NaOH}$ saponification of glyceryl trioleate (triolein).

Draw the condensed structural formula for the product of the hydrogenation of the following triacylglycerol:

Draw the condensed structural formulas for all the products that would be obtained when the triacylglycerol in problem $15.37$ undergoes complete hydrolysis.

Describe the similarities and differences between triacylglycerols and glycerophospholipids.

Describe the similarities and differences between lecithin and cephalins.

Draw the condensed structural formula for the cephalin that contains glycerol, two palmitic acids, phosphate, and ethanolamine (ionized).

Draw the condensed structural formula for the lecithin that contains glycerol, two palmitic acids, phosphate, and choline (ionized).

Identify the following glycerophospholipid, which is found in the nerves and spinal cord in the body, as a lecithin or cephalin, and list its components:

Identify the following glycerophospholipid, which helps conduct nerve impulses in the body, as a lecithin or cephalin, and list its components:

Identify the following features of this phospholipid, which is abundant in the myelin sheath that surrounds nerve cells:

a. Is the phospholipid formed from glycerol or sphingosine?

b. What is the fatty acid?

c. What type of bond connects the fatty acid?

d. What is the amino alcohol?

Identify the following features of this phospholipid, which is needed for the brain and nerve tissues:

a. Is the phospholipid formed from glycerol or sphingosine?

b. What is the fatty acid?

c. What type of bond connects the fatty acid?

d. What is the amino alcohol?

What are the similarities and differences between the adrenal hormone cortisone and the synthetic corticoid prednisone?

Which of the following are steroid hormones?

a. cholesterol

b. cortisol

c. estradiol

d. testosterone

Which of the following are adrenal corticosteroids?

a. prednisone

b. aldosterone

c. cortisol

d. testosterone