Chapters 11-12

Question 1

Draw the important monosaccharides as fisher projections

Answer 1

Question 2

Enantiomers vs Epimers vs Diastereoisomers

Answer 2

Question 3

Draw the mechanism from the fisher projection of d- glucose to alpha-d-glucopyranose and beta-d- glucopyranose

Answer 3

These are anomie’s of each other
beta form predominates since it is not reactive

Question 4

Draw the fisher projection and cyclic form of fructose

Answer 4

Question 5

Draw important disaccharides; sucrose, lactose and maltose

Answer 5

sucrose- Anomeric carbon of glucose is linked to anomeric carbon of fructose
lactose- galactose linked to glucose
maltose- two glucose molecules

Question 6

Reducing sugar vs non-reducing

Answer 6

reducing sugars include aldoses with a free OH these can react with oxidizing agents and can adopt linear structures in solution
they react with free amino groups like R and K to form a stable covalent bond

Question 7

What solution tests for the presence of sugar with an open structure

Answer 7

Fehling’s solution that has copper ions

Question 8

What is glycation,
advanced glycation end products

Answer 8

non enzymatic addition of a carbohydrate to another molecule
AGEs- products resulting from cross-linking following primary modification

Question 9

Why are phosphorylated sugars important intermediates in energy generation s

Answer 9

they have increase reactivity, polarity and charge so they are more likely to break down and form ATP

Question 10

Complex carbohydrates are built by the linkage or 2 or more monosaccharides by _____ bond

Answer 10

O- glycosidic bonds
bond between the 1st carbon and the oxygen of the alcohol

Question 11

Important polysaccharides: glycogen

Answer 11

Question 12

cellulose and starch and glycogen

Answer 12

the beta 1-4 linkage factors straight chains suitable for structure purposes
the alpha 1-4 linkage favor bent structures suitable for storage

Question 13

Carbohydrates can be linked to proteins to form
N-linkage, sugars attached to N in …
O-linkage, sugars attached to O of ….

Answer 13

glycoproteins;
Asn
Ser or Thr

Question 14

What general class of enzymes in missing in somebody with an O blood group versus somebody with an A blood group?

Answer 14

glycosyltransferases

Type A transferase adds N-acetylgalactosamin to form Antigen a
tYPE B transferase adds galactose to form the B antigen
both added through an alpha-1,3 linkage

Question 14

classes of glycoproteins

Answer 14

Question 15

Influenza virus binds to what sugar moiety on the cell surface?
What protein does tamiflu target to stop the spread of virus to new cells

Answer 15

sialic acid; neuraminidase

Question 16

Mass of an oligosaccharide can be determined by

Answer 16

MALDITOF or other mass spectrometry techniques

Question 17

Lectins

Answer 17

bind to specific carb structures on neighboring cell surfaces by a number of weak non covalent interactions
C Type in animals
Selectins bind immune-system cells inflammatory response
L Type in plants

Question 18

Fluid Mosaic Model

Answer 18

The name of the model used to describe the lipid membrane. It’s called this because the majority of elements are not fixed on the membrane and instead move around freely like in a fluid. Lateral diffusion

Question 19

what are fatty acids

Answer 19

long non polar hydrocarbon chains that terminate with carboxylic acid groups

Question 20

Structure of phospholipid based on glycerol

Answer 20

Question 21

Different alcohols you can add to the skeleton of phospholipid

Answer 21

Question 22

Draw phosphatidyl ethanolamine

Answer 22

Question 23

Draw sphingomyelin

Answer 23

Question 24

Draw Cerebroside

Answer 24

Question 25

Archaeal membrane phospholipids are _______ Prokaryotes and eukaryotes have _______ membrane phospholipids The model used to describe the membrane of cells is the _________ Membranes are ________ Proteins don’t______across the membrane but they can move around ________if they are not anchored to the cytoskeleton. Hydropathy plots: predict ________

Answer 25

ETHER LINKED (more resistant to hydrolysis) ESTER LINKED(more reactive) fluid mosaic model asymmetric flip flop; laterally transmembrane alpha helices

Question 26

In Cold temperatures, Cholesterol _______membrane fluidity In Hot temperatures, Cholesterol _______membrane fluidity

Answer 26

increases decreases

Question 27

Permeability of molecules across membrane most permeable?

Answer 27

water- no full charge, very small, high concentration

Question 28

Cholesterol drawing

Answer 28

Question 29

Fructofuranose vs fructopyranose drawings

Answer 29

Question 30

bacteriorhodopsin

Answer 30

light-powered proton pump in archaea – integral membrane protein – composed almost entirely of α helices synthesize ATP through proton gradient

Question 31

Alpha helices vs beta strands

Answer 31

alpha helices contain hydrophobic AAs to interact/ stabilize tails, most common motifs in membrane proteins antiparallel beta sheet can form channel proteins called porins that can carry polar molecules across membrane outer surface is non polar while inner surface is hydrophilic and filled with water

Question 32

lipid rafts =

Answer 32

membrane domains containing such complexes that exhibit reduced fluidity – may induce conformational changes in membrane proteins to regulating their functional activities – may function in signal transduction by providing a favorable environment for specific protein–protein interactions

Question 32

Free iron is toxic to cells and tightly bound to transferrin in the bloodstream. * Complex formation between the transferrin receptor and iron-bound transferrin initiates receptor-mediated endocytosis. – leads to internalization of these these complexes within vesicles (endosomes)

Question 33

SNARE proteins =

Answer 33

guide membrane fusion to ensure specificity – draw appropriate lipid bilayers together through the formation of tightly coiled four-helical bundles – largely determine the compartment with which a vesicle will fuse

Question 34

homotropic effects =

Answer 34

cooperative effects of substrates on allosteric enzymes – act on enzyme active sites – generate the sigmoidal curve – impact ATCase activity by altering the T/R ratio

Question 35

heterotropic effects =

Answer 35

effects of nonsubstrate molecules on allosteric enzymes – bind at sites other than the active site – shift the KM – impact ATCase activity by altering the T/R ratio

Question 36

Hemiacetal and hemiketal

Answer 36

Question 37

Diabetes

Answer 37

D-glucose reacts with hemoglobin to form glycated hemoglobin (hemoglobin A1c, A1C). – has no effect on O2 binding * In nondiabetic individuals, <6% of the hemoglobin is glycated. * In patients with uncontrolled diabetes, almost 10% of the hemoglobin is glycated

Question 38

glycogen vs starch

Answer 38

Glycogen (animals) is a very large, branched polymer of glucose residues (-1,4-glycosidic bonds with -1,6-glycosidic bonds for branches approximately every tenth residue); * Starch (plants): amylose, unbranched form; amylopectin -1,4-glycosidic bonds only: the branched form, 1 -1,6-glycosidic bond per 30 -1,4-glycosidic bonds.

Question 39

glycoprotein types composition

Answer 39

glycoproteins = predominantly proteins – play a variety of roles, including cell adhesion * proteoglycans = predominantly carbohydrates and the protein component is conjugated to a glycosaminoglycan – function as structural components and lubricants * mucins (mucoproteins) = predominantly carbohydrates and the protein components is extensively glycosylated at Ser or Thr residues, usually by N-acetylgalactosamine – key component of mucus – function as lubricants