Biochemistry, Chapter 5 –major compounds of the body
1. Loss of electrons:
a. Oxidation
2. Gain of electrons:
a. Reduction
3. Which is more oxidized, an alcohol or and aldehyde?
a. The carbon atom becomes more oxidized as it goes from an alcohol or an aldehyde or
ketone
4. Carbon-carbon double bonds are more or less oxidized than carbon-carbon single bonds??
a. MORE!
5. The suffix “-ate” ALWAYS DENOTES A NEGATIVE CHARGE!
a. Ex: phosphate group
6. N has 5 valence electrons in its shell—if only 3 are bound it has no charge, but at physiological
pH amines carry a + charge because there pka is 9 (below the pka = protinated!)
7. N bound to one C is a _______ amine.
a. Primary
8. N bound to 4 Cs is a ________ amine.
a. Quaternary amine
9. C-O, C-N, C-S bonds are:
a. POLAR! In each case the C holds a partial + charge
10. Cs in a chain are numbered starting with the most oxidized carbon (ex: -C=O, this carbon would
be labeled 1)
11. In a different system of naming Cs are given greek letters:
a. The C next to the most oxidized C ( the –c=O) is alpha, the next is beta, the next is
gamma and so on
12. Sugars end in the suffix:
a. “-ose”
b. They are either a ketose or an aldose depending on the position of the carbonyl group
13. Monosaccharides are designated D or L, based on the position of the –OH group farthest from
the carbonyl group, is D or L the major series present in humans?
a. D
14. Steroisomers have the same chemical formula but differ in the position of the –OH group in 1+
locations, stereoisomers that differ in the position of only 1 –OH group are called:
a. Epimers
15. Example of epimers:
a. D-glucose and D-galactose (differ at C4)
b. D-glucose and D-mannose (differ at C2)
16. Monosaccharides exist in solution mainly as rings, the original carbonyl carbon is known as the:
a. Anomeric carbon
b. w/in the ring the anomeric C will be the one attached to the O of the ring and w/an –OH
chain
17. if the –OH group on the anomeric C is below the ring it is:
a. alpha
18. if the –OH group on the anomeric C is above the ring it is:
a. beta
19. the hydroxyl group may chain spontaneously from alpha to beta, this is called:
a. mutarotation
20. sugars may be oxidized or reduced
a. an oxidized sugar will lose an H and become negative and its name will change from “ose” to “onic acid” or “-onate”
b. if a sugar is reduced all of the C atoms contain:
i. alcohol! (-OH group)
ii. the name is changed from “-ose” to “-ol”
21. the –OH group of the anomeric C can react with an –OH or –NH group to form a:
a. glycosidic bond
22. glycosidic bonds can be:
a. alpha or beta
23. N glycosidic bonds are found:
a. In nucleosides and nucleotides
b. Ex: the adenine attached to ATP is via beta-N glycosidic bond!
24. O glycosidic bonds are found:
a. Joining sugars
25. Lactose is a_________________ bond.
a. Beta 1-4 O glycosidic bond
26. FAs are straight aliphatic chains w/a methyl group at one end a carboxyl group at the other end,
the methyl end is known as the ____ end.
a. w
b. the Cs are numbered beginning w/the carboxyl group as 1
27. Most common saturated FAs in cells:
a. Palmitic acid (C16)
b. Stearic acid (C18)
28. The melting point of a FA ________ w/chain length
a. Increases
29. The melting point of a FA ________ w/degree of saturation
a. Decreases
30. Therefore FAs w/many double bonds (like those in veg. oil) are liquid at room temp and have
higher melting points than saturated FAs (like those in butter)
31. Oleic acid is denoted: 18:1(9) by one system of naming and w9 by the other system, what do
each of these mean??
a. 18:1(9) the 18 indicates the number of Cs, the 1 indicates the number of double
bonds (so this is a monounsaturated FA), and the 9 means that the position of the
double bond is between C9 and C10
b. W9 denotes that the distance of the double bond closest to the w end is located at C9
32. Arachidonic acid is a polyunsaturated FA denoted as 20:4 (5)(8)(11)(14), how would it be named
as a w FA??
a. W6
33. Palmitoleic acid is a monounsaturated FA denoted as w/16 Cs that is denoted as w7, how could
you name it another way??
a. 16:1(9)
34. Double bonds in naturally occurring fats are in ____ configuration
a. Cis this mean hydrogens are on the same side of the double bond
35. Phosphoacyleglycerols contain FAs esterified to positions 1 & 2 of glycerol and a phosphate
attached to carbon 3. Phosphatidylcholine is one of the major phophoacylglycerols found in
membranes it is amphipathic and also called:
a. Lecithin
36. Amphipathic means:
a. Polar and non polar regions in the same molecule
37. A triacyleglycerol is a glycerol w/ 3 FAs attached thru:
a. Ester linkages (via the –OH groups of the glycerol and the acyl group (-c=o) of the FA)
38. Sphingolipids are derivatives of:
a. Ceramide
b. Ceramide is formed from:
i. Sphingosine which is derived from serine and the FA palmitate
39. Steroids contain a 4 ring structure called the:
a. Steroid nucleus
40. What is the steroid precursor in humans from which all steroid hormones are synthesized?
a. Cholesterol
b. Cholesterol is composed of:
i. Isoprenyl units (5Cs w/1 double bond)
41. Nitrogen is component of ring structures called nitrogenous bases, examples of these are:
a. Purines -2 rings, ex: adeninie, guanine
b. Pyrimidines – 1 ring, ex: thymine
c. Pyridines –ex: niacin, pyridoxine (vit B6)
42. A nucleoside consists of:
a. Nitrogenous base joined to a sugar
43. A nucleotide consists of:
a. A nucleoside w/ a phosphate group
44. A compound in which the H and double bond have changed position is called a:
a. Tautomer
b. Ex: uric acid and urate
45. Free radicals have a:
a. Single electron—these are agents of cell death and destruction and are involved in all
chronic disease states
46. Cig smoking and smog generate:
a. Nitrogen dioxide (NO2) potent toxic radical
47. Uric acid has 2 rings and is similar in structure to a purine, it is not very soluble in water and
when present in excess sodium urate tends to precipitate in the joints and causes:
a. Gout
b. At physiologic pH uric acid has dissociated to form urate which is not water soluble,
besides causing gout it can also cause kidney stones
48. Cholesterol is composed almost entirely of –CH2 groups and is therefore nonpolar and
________.
a. Water insoluble
b. So is estradiol!!
49. Cholic acid is a bile salt derived from cholesterol, it contains a hydrophilic carboxyl group and is
therefore much more ____________ than cholesterol and estradiol.
a. Water soluble
50. Sphingomyelin is a component of the myelin sheath around Ns, it is composed of a
phophorylcholine group attached to a ____________.
a. Ceramide!
51. Linolenic acid as an 18:3 (9)(12)(15) FA, how else could you name it?
a. W3
52. Put these FAs in order from highest to lowest melting point: stearic acid 18:0, arachidonic acid
20:4(5)(8)(11)(14) and palmitoleic acid 16:1(9)
a. Stearic acid, palmitoleic acid, arachidonic acid