BIOC 2580 Final Exam Review
Questions with Solved Solutions 2025
Updated.
Commonly occurring saturated fatty acids - Answer 1. Laurate - 12 Carbons
2. Myristate - 14 Carbons
3. Palmitate - 16 Carbons
4. Stearate - 18 Carbons
5. Arachidate - 20 Carbons
Features of commonly occurring fatty acids - Answer 1. Have an even number of carbon atoms
2. Unbranched
3. Double bonds commonly found in a cis configuration (introduces kinks)
4. PUFAs have methylene-bridged bonds (not conjugated)
5. Bond pattern = double-single-single-double
Solubility and Melting Point of Fatty Acids - Answer Solubility
decreases as the chain length increases
Melting Point
decreases as the chain length decreases
decreases as the number of double bonds increases
Derivatives of fatty acids - Answer 1. Alcohol + Carboxylic acid = Ester
2. Acid + Carboxylic acid = Acid Anhydride
Triacylglycerols (triglycerides) - Answer A glycerol molecule esterified to three fatty acid
molecules; the most common form of fat storage in the body
Overall nonpolar and hydrophobic
Reactions with phosphoric acid - Answer 1. Phosphoric acid + Alcohol = Phosphate ester
,- Phosphorylation adds negative charges to molecules leading to an INCREASE in water solubility
Glycerophospholipids (phosphoglycerides) - Answer - Glycerol backbone bound by ester
linkages to two fatty acids and phosphodiester link to polar head
- Amphiphatic
- Form lipid bilayers
Amphiphatic - Answer A chemical or molecule that has a hydrophilic head and hydrophobic
tail used to transport fat
Lipids aggregate into structures in water - Answer - Fatty acids aggregate to form roughly
spherical micelles
- Hydrophobic tails of phospholipids are too bulky to pack together; aggregate into bilayers,
which spontaneously fold back on themselves to form liposomes or vesicles
Micelles are - Answer lipids surrounded by bile salts
Analysis of Lipids - Answer - homogenized in chloroform/methanol/water
- separated based on polarity on a column of silica gel or through TLC
- trans-esterification
- then gas-liquid chromatography or high-performance liquid chromatography is used to
separate the fatty acids
Adsorption chromatography - Answer a technique in which solute equilibrates between the
mobile phase and adsorption sites on the stationary phase
Thin Layer Chromatography (TLC) - Answer non-polar lipids move father than the polar lipids
Carbohydrates - Answer the starches and sugars present in foods
Chemical properties of monosaccharides - Answer - very water-soluble
- poorly soluble in inorganic solvents (ether or hexane)
- colourless
, 2. at least TWO carbons bearing hydroxyl (alcohol) groups
Trioses - Answer three carbon sugars
Fisher Projection - Answer - Horizontal lines = wedges/ out of the page
-Vertical lines = dashed/ into the page
Perspective Formula - Answer - Solid wedge shaped bonds project in-front
- Dashed bonds point away
Monosaccharides contain ______________________ - Answer chiral carbons, which give rise
to the occurrence of optically active isometric forms
Enatiomers - Answer - mirror images that differ at every chiral carbon atom
- commonly called "left-handed" and "right-handed" forms
- have IDENTICAL chemical properties
- DIFFER in optical activity
Diastereomers - Answer - monosaccharides with more than one chiral carbon with
stereoisomers that differ in handedness at some carbon atoms but not others
- do NOT have the same chemical properties
Sugars are named as ____ "right-handed" or L "left-handed" sugars, depending on how they are
drawn in a Fischer projection - Answer D, L
D and L sugars - Answer - A sugar is a "D" sugar if the chiral carbon atom furthest away from
the carbonyl group has the same configuration as D-glyceraldehyde
Epimers - Answer Pair of sugars that is identical except for the configuration at one carbon
atom
A sugar with n chiral centres has 2^n stereoisomers - Answer ex: An aldose with 5 carbons has
3 chiral centres
Questions with Solved Solutions 2025
Updated.
Commonly occurring saturated fatty acids - Answer 1. Laurate - 12 Carbons
2. Myristate - 14 Carbons
3. Palmitate - 16 Carbons
4. Stearate - 18 Carbons
5. Arachidate - 20 Carbons
Features of commonly occurring fatty acids - Answer 1. Have an even number of carbon atoms
2. Unbranched
3. Double bonds commonly found in a cis configuration (introduces kinks)
4. PUFAs have methylene-bridged bonds (not conjugated)
5. Bond pattern = double-single-single-double
Solubility and Melting Point of Fatty Acids - Answer Solubility
decreases as the chain length increases
Melting Point
decreases as the chain length decreases
decreases as the number of double bonds increases
Derivatives of fatty acids - Answer 1. Alcohol + Carboxylic acid = Ester
2. Acid + Carboxylic acid = Acid Anhydride
Triacylglycerols (triglycerides) - Answer A glycerol molecule esterified to three fatty acid
molecules; the most common form of fat storage in the body
Overall nonpolar and hydrophobic
Reactions with phosphoric acid - Answer 1. Phosphoric acid + Alcohol = Phosphate ester
,- Phosphorylation adds negative charges to molecules leading to an INCREASE in water solubility
Glycerophospholipids (phosphoglycerides) - Answer - Glycerol backbone bound by ester
linkages to two fatty acids and phosphodiester link to polar head
- Amphiphatic
- Form lipid bilayers
Amphiphatic - Answer A chemical or molecule that has a hydrophilic head and hydrophobic
tail used to transport fat
Lipids aggregate into structures in water - Answer - Fatty acids aggregate to form roughly
spherical micelles
- Hydrophobic tails of phospholipids are too bulky to pack together; aggregate into bilayers,
which spontaneously fold back on themselves to form liposomes or vesicles
Micelles are - Answer lipids surrounded by bile salts
Analysis of Lipids - Answer - homogenized in chloroform/methanol/water
- separated based on polarity on a column of silica gel or through TLC
- trans-esterification
- then gas-liquid chromatography or high-performance liquid chromatography is used to
separate the fatty acids
Adsorption chromatography - Answer a technique in which solute equilibrates between the
mobile phase and adsorption sites on the stationary phase
Thin Layer Chromatography (TLC) - Answer non-polar lipids move father than the polar lipids
Carbohydrates - Answer the starches and sugars present in foods
Chemical properties of monosaccharides - Answer - very water-soluble
- poorly soluble in inorganic solvents (ether or hexane)
- colourless
, 2. at least TWO carbons bearing hydroxyl (alcohol) groups
Trioses - Answer three carbon sugars
Fisher Projection - Answer - Horizontal lines = wedges/ out of the page
-Vertical lines = dashed/ into the page
Perspective Formula - Answer - Solid wedge shaped bonds project in-front
- Dashed bonds point away
Monosaccharides contain ______________________ - Answer chiral carbons, which give rise
to the occurrence of optically active isometric forms
Enatiomers - Answer - mirror images that differ at every chiral carbon atom
- commonly called "left-handed" and "right-handed" forms
- have IDENTICAL chemical properties
- DIFFER in optical activity
Diastereomers - Answer - monosaccharides with more than one chiral carbon with
stereoisomers that differ in handedness at some carbon atoms but not others
- do NOT have the same chemical properties
Sugars are named as ____ "right-handed" or L "left-handed" sugars, depending on how they are
drawn in a Fischer projection - Answer D, L
D and L sugars - Answer - A sugar is a "D" sugar if the chiral carbon atom furthest away from
the carbonyl group has the same configuration as D-glyceraldehyde
Epimers - Answer Pair of sugars that is identical except for the configuration at one carbon
atom
A sugar with n chiral centres has 2^n stereoisomers - Answer ex: An aldose with 5 carbons has
3 chiral centres
