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Flashcards in Test 1 Deck (71):
1

Reduction of the terminal aldehyde (-CHO) group @ C1 in glucose or aldose generates?

Glucitol (Sorbitol) or Alditol

2

Sucrose
Chemical nomenclature
Found in?

α-D-glucopyranosyl-(1→2)-β-D-fructofuranose
α-D-glucose-(1→2)-β-D-fructose
Sugarcane

3

Lactulose
Chemical nomenclature
Found in? Can be created by?

β-D-galactopyranosyl-(1→4)-β-D-fructofuranose
β-D-galactose-(1→4)-β-D-fructose
Laxative. Heating milk!

4

D-Mannose
Structure is? # of stereoisomers?
Epimer of glucose at?

Aldohexose sugar (6 C), 4 chiral centers
2^4 = 16
C2

5

GPCRs
what kind of transmembrane topological fold?

Seven-helical fold

6

KcsA
What is it?
Forms?
What does it mediate?

Bacterial ion channel (only open/close when needed)
α-helical cone-like tunnel
K+ ions from inside to outside in highly specific manner

7

OmpF
What is it?
Forms?
What does it mediate?

Porin Channel
β-barrel
Non-selective diffusion of polar and charged molecules

8

Integral membrane proteins
Traverse bilayer how often?
Adopt what kind of fold?
May undergo what kind of diffusion?

One or more times
α-helical or β-barrel
Lateral within plane of bilayer

9

RTKs
what kind of transmembrane topological fold?

Single-helical fold

10

Membrane proteins
what kind of transmembrane topological fold?

β-barrel fold

11

van der Waals radius
In Angstroms, nanometers, and picometers

1.4 A
0.14 nm
140 pm

12

D-Fructose
Structure is? # of stereoisomers?

Ketohexose sugar (6 C), 3 chiral centers
2^3 = 8

13

Na+/glucose symporter
Requires energy in what form?
Mediates transport of what two things and in what direction?

Discharge of Na+ ion gradient
Na+ and glucose in

14

Insulin
Binds to what type of receptor?
Secreted by?
What kind of hormone?

RTK
Islets of Langerhans
Hydrophilic peptide hormone

15

D-Glyceraldehyde
Structure is? # of stereoisomers?

Aldotriose sugar (3 C), 0 chiral centers

16

Passive Transport
Energy?
Diffusion of?
Entropy?

No input of energy
Apolar diffusion
Increase in entropy

17

AQP1
What is it?
Forms?
What does it mediate?

Aquaporin channel abundantly expressed in kidney cells
α-helical bundles (tetramer)
Water

18

What happens to chirality upon cyclization?

The anomeric carbon counts as a chiral carbon (+1 chiral center)

19

Proteoglycans
Architecture? Composed of?
Bristles made of?
Smaller oligosaccharides attach how?

Bottle-brush with hyaluronan backbone noncovaently linked to glycoproteins
Core protein plus GAGs linked by sidechain hydroxyl of S and T (O-linked glycan)
Covalently to core by asparagine (N-linked glycan)

20

Ca+ antiporter
Requires energy in what form?
Mediates transport of what two things and in what direction?

directly-coupled ATP hydrolysis
Ca+ out
H+ in

21

D-Glucose
Structure is? # of stereoisomers?

Aldohexose sugar (6 C), 4 chiral centers
2^4 = 16

22

Standard State Conditions

T = 25 C = 298 K
P = 1 atm = 760 mmHg
pH = 7.0

23

Valinomycin
What is it?
Forms?
What does it mediate?

Ionophore Carrier
12 alternating amide and ester linkages and a macrocyclic dodeca-depsipeptide antibiotic (cyclic)
K+

24

Ice differs from liquid water:
What kind of network?
How many neighbors?
Density vs liquid?

Tetrahedral network in ice
Four neighbors in ice
Density of ice lower than liquid water

25

Estradiol binds to what type of receptor?

SHR

26

Heparin
What is it?
Made of? Linkage?
Used as?

Glycosaminoglycan (GAG and heteroglycan)
Iduronate-2-sulfate linked to N-sulfo-glucosamine-6-sulfate via the (α1→α4) intra-glycosidic linkage
Anti-coagulant

27

Oxidation of the terminal aldehyde (-CHO) group @ C1 in glucose or aldose generates?

Gluconic Acid or Aldonic Acid

28

Fatty acid with x:y has how many stereoisomers?

2^y
y = # of C=C bonds

29

Hyaluronan
What is it?
Made of? Linkage?
Found in?

Glycosaminoglycan (GAG and heteroglycan)
Glucuronate linked to N-acetyl-glucosamine via the (β1→β3) intra-glycosidic linkage
ECM at joints

30

Trehalose
Chemical nomenclature
Found in?

α-D-glucopyranosyl-(1→1)-α-D-glucopyranose
α-D-glucose-(1→1)-α-D-glucose
Brine shrimp and cosmetics

31

Dihydroxyacetone
Structure is? # of stereoisomers?

Ketotriose sugar (3 C), 0 chiral centers

32

Deoxyribose sugar differs from ribose in that ribose has OH group at

C2'

33

Epimers

Differ at only one chiral center
(special case of diastereomers)

34

Gramicidin A
What is it?
Forms?
What does it mediate?

Ionophore Channel
Linear pentadeca-peptide (15-mer) and head-to-head helical dimer
Membrane transit of K+ (slightly less, Na+)

35

Globular (water-soluble) proteins
what kind of transmembrane topological fold?

α-helical bundle

36

Gibb's Free Energy in terms of Ka and Kd
R and T values?

RTlnKd
-RTlnKa
Ka = 1/Kd
R = 2 cal/mol*K
T = 25 C or 298 K

37

Two stereoisomers are enantiomers if
Configuration?
What kind of image?
Rotate light how?

Different at ALL chiral centers
Non-superimposable mirror images
Rotate plane of polarized light in opposite directions by equal amounts

38

Lipid comprised of glycerol moiety esterified to three fatty acids is

Triglyceride

39

Closest distance two water molecules can approach?
In Angstroms, nanometers, and picometers

2.8 A
0.28 nm
280 pm
(2r)

40

Phosphoglycerol derivatives of fatty acids are

Phospholipids

41

Carboyxlic acids with long aliphatic tails are

Fatty Acids

42

Derivatives of steranes are

Steroidolipids

43

D-Ribose
Structure is? # of stereoisomers?

Aldopentose sugar (5 C), 3 chiral centers
2^3 = 8

44

Enantiomers

differ at all chiral centers

45

Derivatives of ceramides are

Sphingolipids

46

Starch
What is it?
3D Structure?

Storage homoglycan mixture of amylose (α1→α4) and amylopectin (α1→α6 branch every 30 units)
Coiled-coil conformation

47

Chemical Potential Difference Mu formula

RTln(Ccyt/Cext)

48

Maltose
Chemical nomenclature
Found in?

α-D-glucopyranosyl-(1→4)-α-D-glucopyranose
α-D-glucose-(1→4)-α-D-glucose
Beer

49

Activation of GPCRs causes

Phospholipase C catalyzes conversion of phosphatidylinositol biphosphate to inositol triphosphate and diacylglycerol
Inositol triphosphate triggers Ca2+ ER channels
Diacylglycerol activates PKC

50

Pentose
Hexose
Pyranose
Furanose

Sugar with 5 C chain
Sugar with 6 C chain
Sugar with 6-membered cyclic ring
Sugar with 5-membered cyclic ring

51

A reaction is at equilibrium when

Forward = reverse
*death*

52

Glucagon binds to what kind of receptor?
What kind of hormone?

GPCR
Hydrophilic peptide hormone

53

Diastereomers

differ in one or more chiral centers (epimer is case of)

54

Tetrahedron
How many triangular faces?
How many vertices (or corners)
How many straight edges?

4 triangular faces
4 vertices/corners
6 straight edges

55

GLUT1
Transport channel/tunnel operates how?
Mediates transit of?
Adopts what topology?

Allosterically-gated without external energy
Glucose and vitamin C
12-transmembrane α-helical topology

56

MSPs required for

Nanodiscs

57

Chitin
What is it?
3D Structure?

Structural homoglycan made of β1→β4 N-acetylglucosamine linkages
Extended conformation

58

Lactose
Chemical nomenclature
Found in?

β-D-galactopyranosyl-(1→4)-β-D-glucopyranose
β-D-galactose-(1→4)-β-D-glucose
Milk

59

A reaction is at steady-state when

Rate of synthesis = rate of degradation
*life*

60

pH in terms of Ka
what is pKa?

pH = pKa +log[A-/HA]
pKa = -logKa

61

Melting point of fatty acids increases with?
Answer in length, degree of saturation, # of C-C bonds, and # of C=C bonds

Increasing length (# of C-C bonds)
Increasing degree of saturation (lowering # of C=C bonds)

62

Oxidation of the terminal aldehyde (-CHO) group @ C6 in glucose or aldose generates?

Glucuronic Acid or Alduronic Acid

63

Chondroitin Sulfate
What is it?
Made of? Linkage?
Found in?

Glycosaminoglycan (GAG and heteroglycan)
Glucuronate linked to N-acetyl-galactosamine-6-sulfate via the (β1→β3) intra-glycosidic linkage
ECM at joints

64

Na+/K+ antiporter
Requires energy in what form?
Mediates transport of what two things and in what direction?

directly-coupled ATP hydrolysis
Na+ out
K+ in

65

Glycogen
What is it?
3D Structure?

Storage homoglycan mixture of amylose (α1→α4) and amylopectin (α1→α6 branch every 10 units)
Coiled-coil conformation

66

Facilitated Transport
Energy?
Gradient?
Mediates transfer of?

No external input of energy
Along concentration gradient
Polar and Charged Substances

67

Cellulose
What is it?
3D Structure?

Structural homoglycan made of β1→β4 glucose linkages
Extended conformation

68

D-Ribulose
Structure is? # of stereoisomers?

Ketopentose sugar (5 C), 2 chiral centers
2^2 = 4

69

Keratan Sulfate
What is it?
Made of? Linkage?
Found in?

Glycosaminoglycan (GAG and heteroglycan)
Galactose linked to N-acetyl-glucosamine-6-sulfate via the (β1→β4) intra-glycosidic linkage
ECM at the joints and cornea

70

D-Galactose
Structure is? # of stereoisomers?
Epimer of glucose at?

Aldohexose sugar (6 C), 4 chiral centers
2^4 = 16
C4

71

Testosterone
Binds to what kind of receptor?
What kind of hormone?

SHR
Lipophilic steroid hormone (passive transport)