Biochemistry - Carbohydrates & Lipids

Question 1

Aldose examples

Answer 1

Glucose, Galactose, Ribose, & Mannose

Question 2

Ketose examples

Answer 2

Fructose & Sedoheptulose

Question 3

Stereoisomers

Answer 3

Same chemical formula but different position of one or more hydroxyl group

Question 4

Epimers

Answer 4

Stereoisomers with difference in rotation of hydroxyl group at one carbon

Question 5

Enantiomers

Answer 5

Mirror images, possesses possible identical chemical characteristics, occurs are either D or L. Naturally occurring sugars occur in the D conformation.

Question 6

Glycation

Answer 6

Non-enzymatic covalent linear monosaccharide addition to protein. Forms Schiff bases (linear monosaccharide attached to a protein.) Schiff bases can oxidize to form Advance Glycation End (AGE) products.

Question 7

Glycosylation

Answer 7

Enzymatic covalent oligio/polysaccharide addition to proteins/lipids (Purposeful). Occurs in the ER and Golgi through Post-Translational Modification, results in glycollipids or glycoproteins.

Question 8

Glycosaminoglycans

Answer 8

Linear polymers of repeating disaccharides that form the ground substance of the EM, Negatively charged at physiological pH allowing water absorptive qualities.

Question 9

Glycosides

Answer 9

Sugar bonded to oxygen or nitrogen based functional groups

Question 10

O-linked glycosidic bonds

Answer 10

Found in Sugar-Sugar or Sugar-Protein attachment

Question 11

N-linked glycosidic bonds

Answer 11

Found in nucleosides & nucleotides

Question 12

Reduced sugars (Sugar Alcohols)

Answer 12

Sugars reduced at the aldehyde carbon.

Question 13

Sorbitol

Answer 13

Reduced glucose

Question 14

Galactitol

Answer 14

Reduced galactose

Question 15

Iduronic acid

Answer 15

Oxidized glucose

Question 16

glucuronic acid

Answer 16

Oxidized Galctose

Question 17

Omega-6 Linolenic acid

Answer 17

a precursor for arachidonic acid, which is a precursor for eicosanoids

Question 18

Omega-3 Linolenic acid

Answer 18

a precursor for other omega-3 fatty acids vital to growth

Question 19

Branched chain fatty acids

Answer 19

Fatty acids with methyl groups on the 3rd carbon (B-carbon), Requires α-oxidation by α-hydroxylase.

Question 20

Refsum disease

Answer 20

Consumption of phytanic acid accumulates due hydroxylase deficiency causing neuronal damage. Treatment: Low phytanic acid/phytanic acid precursor diet.

Question 21

Trans Fatty Acids

Answer 21

Partial hydrogenated vegetable oils, correlated w/ heart diseases.

Question 22

Triacylglycerols (TAG)

Answer 22

Formed by acylation of fatty acids and attachment to glycerol molecule. Storage form of fatty acid. Hydrophobic, non-polar.

Question 23

Steroids

Answer 23

Four ringed structures (Unbreakable by human physiology), derived from cholesterol.

Question 24

Cholesterol Esters

Answer 24

4 ringed, amphipathic molecules (Hydroxyl) & membrane lipid. They have a lower solubility in water than cholesterol and are more hydrophobic. They are associated with atherosclerosis.

Question 25

HB1ac Test

Answer 25

Measurement of glycated hemoglobin, used to understand the adequacy of blood sugar regulation in diabetic patients.

Question 26

Glucuronic acid/glucuronate

Answer 26

Oxidized glucose. Often conjugated/added onto hydrophobic molecules in the liver in order to make the molecule more hydrophilic/polar, thus more soluble and excretable from the body. Known as the second phase of drug metabolism.

Question 27

Niemann Pick Disease

Answer 27

Spingomyelinase deficiency results in accumulated spingomyelin.

Question 28

Tay Sachs Disease

Answer 28

Hexosamindase A deficiency resulting in GM2 ganglioside accumulation.

Question 29

Gaucher disease

Answer 29

Beta Glucosidase deficiency resulting in accumulated GAGs.

Question 30

Hurler syndrome

Answer 30

iduronidase deficiency resulting in accumulated GAGs.

Question 31

Hunter syndrome

Answer 31

Iduronate sulfatase deficiency resulting in accumulated GAGs (not as severe as Hurler).

Question 32

Essential fatty acids

Answer 32

γ−linoleic (ω-6) and α-linolenic acids (ω-3), must ingest them because humans can’t add double bonds on fatty acids past C9 position.

Question 33

Glycerophospholipids

Answer 33

Hydrophobic portion: 2 long chain fatty acids Hydrophilic portion: The phosphate group plus whatever alcohol is attached to.

Question 34

Sphingomyleins

Answer 34

Hydrophobic portion: ceramide Hydrophilic portion: The phosphate group plus choline moiety.

Question 35

Ceramide

Answer 35

One long chain fatty acid attached to sphingosine.

Question 36

Glycosphingolipids

Answer 36

Hydrophobic portion: Ceramide Hydrophilic portion: Carbohydrate group

Question 37

Cholesterol

Answer 37

Hydrophobic portion: A rigid planar steroid ring region and a nonpolar hydrocarbon. Hydrophilic portion: The -OH group.

Question 38

N-Acetylated amino sugars

Answer 38

Contain an amino group substitutes for one of the hydroxyls; an example is glucosamine. They are essential components of glycosaminoglycans, glycolipids and glycoproteins.