Exam 4 Flashcards
(274 cards)
1
Q
what are the most abundant micronutrients on earth
A
carbs
2
Q
what are carb polymers called
A
glycans
3
Q
what important function do they play in joints
A
lubrication
4
Q
what is their primary function in the body
A
energy
5
Q
what are they used for within cells
A
signaling molecules
6
Q
what two functional groups describe all carbs
A
aldehydes
ketones
7
Q
which functional group is most common
A
(CH2O)n
8
Q
what suffix do carbs end in
A
-ose
9
Q
what is a 1 sugar carb called
A
monosaccharide
10
Q
what flavor is a monosaccharide
A
sweet
11
Q
what is the most abundant monosaccharide
A
D-glucose (AKA dextrose)
12
Q
what is a 2 sugar carb called
A
disaccharide
13
Q
what type of bond holds disaccharides together
A
glycosidic bond
14
Q
what flavor are disaccharides
A
sweet
15
Q
what are some examples of disaccharides
A
sucrose and lactose
16
Q
what language and word is saccharide derived from
A
greek; sakcharon
17
Q
what is the sweetest sugar
A
fructose
18
Q
a 3-10 sugar carb is called what
A
an oligosaccharide
19
Q
are oligosaccharides free in a cell
A
no - they are bound to lipids or proteins in glycoconjugates
20
Q
can we digest oligosaccharides
A
no - they are highly fermentable and cause gas
21
Q
a carb with 10 or more sugars is called what
A
a polysaccharide
22
Q
what are polysaccharides primarily used for
A
storage and signaling
23
Q
what are some examples of polysaccharides
A
cellulose, glycogen, starch
24
Q
how many carbons could a monsaccharide have
A
3-7
25
what is the most common number of carbons in a monosaccharide
6
26
what is a 3 carbon sugar called
triose
27
what is a 4 carbon sugar called
tetrose
28
what is a 5 carbon sugar called
pentose
29
what is a 6 carbon sugar called
hexose
30
what is the most important functional carbon called
anomeric carbon
31
where is the anomeric carbon located in an aldose
carbon 1
32
where is the anomeric carbon located in a ketose
carbon 2
33
what is the chemical formula for an aldehyde
CHO
34
what is the chemical formula for a ketone
C=O
35
what is the scientific name of a 5 carbon aldehyde and what is an example
aldopentose
ribose
36
what is the scientific name of a 6 carbon aldehyde and what is an example
aldohexose
glucose and galactose
37
what is the scientific name of a 5 carbon ketone
ketopentose
38
what is the scientific name of a 6 carbon ketone and what is an example
ketohexose
fructose
39
what geometric change creates isomerization in carbs
whether a hydroxyl group is facing left or right
40
why is isomerization so important
it determines function
41
what factor makes one sugar different than all the others
location of hydroxyl groups
42
what is crucial for enzyme interaction
specific hydroxyl patterns
43
What determines if a carb is D or L
position of the OH group on the HIGHEST NUMBER CHIRAL CARBON
44
is D right or left
right
45
is L right or left
L
46
Does D or L reference rotation of polarized light
no
47
are most sugars L or D
D
48
where is the highest numbered chiral carbon usually located
next to the last carbon (above the last CH2OH)
49
what is an epimer
an isomer in which the only difference is the rotation around 1 carbon (type of diastereomer)
50
what does a single line represent in a Fisher Projection
an OH group
51
what form are carbs usually found in
cyclic structures
52
what is a cyclized aldose called
hemiacetal
53
what is a cyclized ketose called
hemiketal
54
what component of the anomeric carbon group makes it vital in becoming a cyclic structure
the double bonded Oxygen
55
what components make up a Pyranose ring (P-ring)
5 Carbon, 1 oxygen
56
what components make up a Furanose ring (F-ring)
4 Carbon, 1 Oxygen
57
why are aldohexoses found in pyranose rings
aldo- implies one CH2OH group.
hexose implies a GRAND TOTAL of 6 carbons.
So there is a total of 6 carbons.
58
why are ketohexoses found in a furanose ring
keto- implies 2 CH2OH groups (5+1)
hexose implies a GRAND TOTAL of 6 carbons.
So there is a total of 6 carbons (4+2)
59
Why are aldopentoses found in a furanose ring
aldo-implies one CH2OH group.
pentose implies a GRAND TOTAL of 5 carbons
So there is a total of 5 carbons (4+1)
60
In a cyclic projection of a carb, what determines if the sugar is D or L
If it is D, the last carbon points up (Dicks go up)
If it is L, the last carbon point down (Lesbians go down)
61
what tells us whether a cyclic carb structure is alpha or beta
the direction of the new OH group on the anomeric carbon once the cyclic structure is formed
62
what direction does the OH group point on an alpha carb
down (fish swim)
*the alpha symbol looks like a fish*
63
what direction does the OH group point on a beta carb
UP (Birds fly)
Beta=Bird
64
if the OH on the anomeric carbon is not bounds to another sugar what can it do
it can open and flip back and forth between alpha and beta
65
what is this flipping phenomenon called
mutarotation
66
what sugar acid found on gangliocides is common in the body
N-acetylneuraminic acid
67
what determines if a sugar is a reducing sugar
if it has a free aldehyde or a free ketone, it is a reducing sugar
68
which two classifications of sugars are always reducing sugars
monosaccharides and discaccharides
69
what do oligosaccharides and polysaccharides have
at least 1 reducing end
70
what is used to test for reducing sugars
FEHLING'S REAGENT
71
what type of reaction creates disaccharides
dehydration/condensation
72
what two elements can be at the center of a glycosidic linkage
Nitrogen or Oxygen
O-glycosidic or N-glycosidic bond
73
what forms glycosidic bonds
glycosyltransferases
74
what must be stated in the naming of a glycosidic bond
the carbons participating
75
can disaccharides be reducing sugars
YES - as long as there is one free anomeric carbon
76
what other factor is necessary in naming a glycosidic bond
the direction of the OH group on the anomeric carbons involved
(alpha or beta)
77
what is the disaccharide formula for maltose
GLUCOSE-alpha(1-->4)-GLUCOSE
78
what are easier to digest, disaccharides with alpha or beta bonds
alpha is easier
79
how many sugars in a polysaccharide
10 or more
80
what is the most abundant type of carb in nature
polysaccharides
81
what are they also known as
glycans
82
what two factors create different polysaccharides
type of sugar and branching locations
83
what are two major functions of polysaccharides
storage and structure
84
where are polysaccharides typically found
extracellularly
85
if all the constituent sugars of a glycan are the same what is the glycan called
a homoglycan
86
if there are multiple types of sugars in a glycan what is the glycan called
heteroglycan
87
what are the four types of complex carbs (polysaccharides)
starch
glycogen
soluble fiber
insoluble fiber
88
is starch a hetero- or homo- glycan
homoglycan
89
is glycogen a hetero- or homo- glycan
homoglycan
90
is soluble fiber a hetero- or homo- glycan
trick question
it can be both
91
is insoluble fiber a hetero- or homo-glycan
it can also be both
92
what is the storage form of carbs in plants
starch
93
what simple sugar is repeated over and over in starch
D-glucose
94
where in the plant is the starch stored
the endosperm
95
what is the storage form of carbs in mammals
glycogen
96
which simple sugar is repeated over and over in glycogen
D-glucose
97
where in mammals is glycogen formed
cytosol of liver and muscle
98
what do both starch and glycogen have a lot of that makes them attract water molecules
hydroxyl groups
99
why are starch and glycogen considered HEAVILY HYDRATED
because of the high number of hydroxyl groups
100
what two compounds is starch made of
amylose and amylopectin
101
what is the only bond found in amylose
glycose-alpha(1-->4)glucose
102
what makes amylopectin different from amylose
it is highly branched
103
what bonds constitutes most of amylopectins bonds
glucose-alpha(1-->4)glucose
104
what bond makes amylopectin unique and how often does it occur in starch
alpha(1-->6) bonds found every 24-30 glucose residues
105
what is starch easily digested into
glucose
106
is starch rapidly absorbed
yes
107
what physiological effect does starch have
causes a significant and rapid rise in blood sugar
108
does the body know the difference between High Fructose corn syrup and naturally occurring fructose
no
109
where are most bonds found in glycogen
alpha(1-->4)
110
which other bond is found and how often is it found
alpha(1-->6) every 8-12 glucose residues
111
how many reducing ends does glycogen have
one
112
what is liver glycogen used for
to regulate blood glucose
113
what feature makes glycogen important in regulating blood sugar
it is quickly and easily broken down when blood sugar is low
114
what is muscle glycogen used for
energy during exercise
115
where does digestion of glycogen begin
at the non-educing ends
116
what is a dextran
a polysaccharide produced by bacteria and yeast
117
are dextrans homo- or hetero- glycans and of what sugar
homoglycan of glucose
118
what glycosidic bonds are found in dextrans
alpha(1-->6)
alpha(1-->3)
alpha(1-->2)
alpha(1-->4)
119
where in humans are dextrans most commonly found
in dental plaque caused by bacteria on teeth
120
what is the most distinguishing trait of dextrans
highly adhesive
121
what factor makes dextrans insoluble
extensive crosslinking
122
what is the definition of dietary fiber
non-digestible carbs and lignin found in plants
123
what action make fiber soluble
it swells in water
124
what action (of lack of) makes a fiber insoluble
does not swell in water
125
what do we call fiber that forms a gel in the gut and is a good fiber
viscous fiber
126
what types of fiber are metabolized by colonic bacteria
fermentable fibers
127
what is a functional fiber
an isolated fiber that has a physiological benefit when consumed (extracts)
128
what are the 6 soluble fibers
```
beta-glucans
gums
wheat dextrin
psyllium
pectin
inulin
```
129
what are the 4 insoluble fibers
cellulose
lignin
some pectins
some hemicelluloses
130
what are the 4 viscous fibers and what other factor do they have in common
pectin
beta-glucans
some gums
psyllium
they are all soluble fibers as well
131
what are the 5 fermentable fibers
```
pectin
beta-glucans
guar gum
inulin
wheat dextran
```
132
what are the 2 non-fermentable fibers
cellulose
| lignin
133
what can soluble fiber bind to when it swells
cholesterol
triglycerides
glucose
134
what effect can this binding have on cholesterol, triglycerides and glucose
it can significantly decrease their absorption
135
what other effect can some of them have that affects satiety
delay gastric emptying which makes you feel fuller longer
136
are they digested
no
137
what happens to some in the large intestine
they are fermented
138
what are they fermented into
short-chain fatty acids and gas
139
what are some examples of fermentable fibers
inside of fruits and vegetables and psyllium
140
what are the short chain fatty acids good produced by fermentation good for
energy
141
is pectin a heteroglycan or homoglycan
heteroglycan
142
what two sugars are found in pectin
galacturonic acid and L-rhamnose
143
how often is an L-rhamnose found in pectin
every 25th sugar
144
which glycosidic bond is found in pectin
linear alpha(1-->4)
145
where is pectin found
inside of fruits and vegetables
146
what is pectin used as industrially
a jelling agent
147
what common product is pectin the active ingredient in
Luden's cough drops
148
what functional group/bond is found on pectin BEFORE RIPENING
methyl esters
149
what do the methyl esters become once they are removed during ripening
methanol gas
150
are gums hetero- or homo- glycans
heteroglycans
151
what types of sugars do gums contain
galactose, glucuronic acid and others
152
what common foods contain gums
oatmeal, legumes and barley
153
are beta-glucans hetero- or homo- glycans
homoglycan
154
what sugar are beta-glucans a homoglycan of
glucose
155
what are beta-glucans important for
decreasing cholesterol, triglycerides and glucose absorption
156
what are fructans
homoglycans of fructose
157
how many fructose residues constitute a fructooligosaccharide
2-10
158
how many fructose residues constitute an inulin
11-60
159
what is a probiotic
an actual bacteria added to food or supplements
160
what is a prebiotic
components that stimulate the growth of good bacteria in the gut
161
where are fructans found
bananas, tomatoes, garlic, etc...
162
which ingredient of Fiber One bars contains inulin that is responsible for the huge amount of gas produced
chicory root
163
what is the major structural component of plants
cellulose
164
cellulose is a homoglycan of what sugar
glucose
165
how many glucose can be found in a single strand of cellulose
300-15,000
166
what type of intermolecular bond is formed that creates the rigid structure
H-bonds
167
is cellulose found in vegetables
yes but mostly in the peel
168
what is the glycosidic bond found in cellulose
glucose-beta(1-->4)-glucose
169
which sugar is chitin a homoglycan of
n-acetylglucosamine
170
which glycosidic bonds are found in chitin
beta(1-->4)
171
what structures in nature is chitin found most abundantly in
exoskeletons of arthropods
172
what supplement is chitin the major source of
glucosamine
173
what is a glycosaminoglycan (GAG)
a heteropolysaccharide (heteroglycan) found in the extracellular matrix
174
what type of repeating sugars are GAGs made of
linear disaccharides
175
what two components make up each disaccharide in a GAG
sugar amine and sugar acid
176
what are the two sugar amines that can be found in GAGs
N-acetylglucosamine
N-acetylgalactosamine
177
what are the two sugar acids that can be found in GAGs
D-glucuronic acid
L-iduronic acid
178
what lifeforms are GAGs found in and more importantly which are they not found in
found in animals and bacteria
not found in plants
179
what attribute makes GAGs good lubricants in the body
low compressibility
180
what do all GAGs have that make them negatively charged
carboxylic acids or sulfates
181
All classes of GAGs contain sulfate except for which one
hyaluronic acid
182
which GAG has the highest molecular weight, is up to 50,000 sugars long per chain and is a lubricator in synovial fluid, tendons and cartilage
hyaluronic acid
183
which is the most abundant GAG in the body
chondroitin sulfate
184
where is keratin sulfate found
cornea, cartilage, bone, hair, nails
185
where is dermatan sulfate found
skin and blood vessels
186
which cells is heparin sulfate found in
all of them
187
what differentiates heparin from heparan
heparin is more sulfated; a derivative of mast cell activity
188
what two micronutrients make up a glycoconjugate
a carb and a protein
189
what are the three major glycoconjugate groups
proteoglycans
glycoproteins
glycosphingolipids
190
which GAG will not bind to proteoglycan monomers
hyaluronic acid
191
what causes the 'bottle brush' structure
the repulsion of the protein core and the GAG
192
what constitutes a proteoglycan aggregate
a protein core with hyaluronic acid noncovalently attracted to it
193
what is an example of a proteoglycan monomer
Aggrecan
194
what is a glycoprotein
a protein + a branched oligosaccharide
195
which protein attached to a carb via a N-link
asparagine
196
which proteins are attached to a carb via an O-link
serine and threonine
197
what are the 4 functions of glycoproteins
cell surface recognition
ABO blood group antigens
biological lubricants
makes mucus slippery (O-linked)
198
most proteins secreted by cells are in what states
glycosylated
199
what are some examples of glycoproteins secreted by cells
immunoglobulins
peptide hormones
milk proteins
200
what produces bacterial lipopolysaccharides
gram negative bacteria like E. coli
201
where are bacterial lipopolysaccharides produced
by bacteria in the gut
202
bacterial lipopolysaccharides are absorbed with our lipids as part of our ______
micelles
203
what can bacterial lipopolysaccharides cause
inflammation
204
what do lipopolysaccharides (LPS) do to insulin resistance
increase it
205
do LPSs have an effect on immune signaling
yes (including prenatal immunity)
206
what joint condition is increased by LPS
osteoarthritis
207
what mental disorder is more likely due to LPS
depression
208
what promotes LPS in the body
high fat diets
209
what receptor proteins read signals sent by oligosaccharides
lectins
210
what are selectins and what is their major function
special lectins that mediate cell-cell interactions
211
what type of cells are P-selectin found on
endothelial
212
what component of a glycoprotein does P-selectin bind to and on what kind of cells
the oligosaccharide on circulating leukocytes (white blood cells)
213
what condition do selectins mediate
inflammatory response
214
how does heliobacter pylori cause stomach ulcers
it contains a lectin (specialzed receptor protein) that adheres to oligosaccharides on the endothelial cells of the stomach
215
what are three most common forms of the carbs we consume
starch
sugar
glycogen
216
what are carb digesting enzymes called
glucosidases
217
what carb digesting enzyme is found in the mouth
salivary alpha-amylase
218
what bonds does salivary alpha-amylase start digesting and in which carbs
alpha(1-->4) bonds in starch and glycogen
219
how does salivary alpha-amylase decide which bonds to digest
it is random
220
what is the digested product of salivary alpha-amylase called
short oligosaccharides called dextrins
221
what happens to salivary amylase in the stomach
it is denatured
222
what digests carbs in the stomach
trick question
no carb digestion takes place in the stomach
223
which bonds do pancreatic alpha-amylase digest and on which carbs
alpha(1-->4) bonds on starch and glycogen
224
what are the digested products of pancreatic alpha-amylase
glucose, maltose and isomaltose
225
what are the 4 small intestine brush border enzymes for carbs
lactase, maltase, sucrose and isomaltase
226
what do these enzymes digest sugars into
monosaccharides
227
what are the digested products of small intestine brush border enzymes
glucose, galactose and fructose
228
what causes lactose intolerance
a deficiency of lactase (brush border enzyme) causes lactose malabsorption
as a result lactose goes to Large intestine and is ferments into short-chain fatty acids and gas
229
what type of carb digestion takes place in the large intestine
none
230
what type of carb is acted upon in the large intestine
soluble fiber is fermented into short-chain fatty acids and gas
231
what happens to insoluble fiber in the large intestine
nothing- it is excreted unchanged in the feces
232
how much energy can be derived from the short-chain fatty acids that are fermented in the large intestine (colonic membrane)
1.5-2 kcal/gram
233
what is the amount of fiber that will start to cause gas issues
>35 grams/day
234
what is the classification of glucose and galactose
aldohexoses (1 CH2OH and 6 total carbons)
235
by which mechanisms are glucose and galactose absorbed INTO THE ENTEROCYTE
via ACTIVE TRANSPORT using SODIUM-GLUCOSE TRANSPORTER-1 (SGLT-1) and ATP
236
what transports the resultant monosaccharides to the liver
the portal vein
237
what transports the monosaccharides out of the enterocyte into the portal blood
GLUT-2 transport protein
238
normally GLUT-2 is found on the basolateral membrane between the enterocyte and the portal blood.
where are they found after a sugar rich meal and why
in the brushborder membrane to help absorb glucose by facilitated diffusion (helps speed up the absorption of glucose, no ATP needed in facilitated diffusion)
239
insulin is released in response to the increase in blood glucose
what does insulin do to the GLUT-2 receptors in the brush border
it pulls them back to the basolateral membrane to decrease glucose absorption
240
which transport protein binds FRUCTOSE
GLUT-5
241
by which mechanism does fructose enter the enterocyte
facilitated diffusion via GLUT-5
242
by which mechanism does FRUCTOSE exit the enterocyte and enter the portal blood
GLUT-2
243
which sugars are transported by glut-2
glucose, galactose and fructose
244
what is the function of GLUT-4
transport GLUCOSE from blood plasma to muscle and adipose tissue
245
what are the four uses of glucose in order corresponding to amount in the blood (low to high)
blood glucose regulation
glycogen stores
other carbs
turned into triglycerides
246
what is a normal fasting blood glucose level
70-99 mg/dL
247
what two peptide hormones regulate blood glucose
insulin and glucagon
248
how many amino acids in insulin
51
249
how many polypeptide chains in make up insulin
2
250
what type of bond holds the two polypeptide chains together
disulfide bridge
251
where is insulin synthesized
beta-cells of the pancrease
252
what are the four factors that will cause secretion of insulin
high plasma glucose [ ]
plasma amino acid levels
CCK
GIP
253
what are the two factors that will inhibit insulin release
low plasma glucose
| stress
254
is insulin a builder or a breaker
builder
255
what three effects does insulin have on carbs
increases liver and muscle glycogen
increases glucose uptake in muscles by making GLUT4
decreases glucose synthesis in the liver
256
what two effects does insulin have on lipids
inhibits breakdown of triglycerides
stimulates triglyceride synthesis
*these two together increase blood serum triglyceride concentration
257
what two effects does insulin have on proteins
stimulates Amino acid uptake by cells
increases protein synthesis
258
based on the amount of glucose present in a cell, what can insulin tell the cell to do with the glucose (low to high levels)
use glucose for ATP
store glucose as glycogen in liver and muscles
turn glucose into triglycerides in the liver
259
how many amino acids make up glucagon
29
260
where is glucagon secreted from
alpha-cells of the pancreas
261
when is glucagon released
when blood sugar is low
262
what three factors cause glucagon to be released
low blood plasma glucose
plasma amino acid levels
epinephrine or norepinephrine
263
what two factors will inhibit glucagon release
high blood plasma glucose
insulin
264
is glucagon a builder or a breaker
breaker
265
what effect will glucagon have on carbs
degradation of liver glycogen
266
what effect will glucagon have on lipids
stimulates TG breakdown
267
what effects will glucagon have on proteins
stimulate AA uptake by liver
increases gluconeogenesis (new glucose) from glucogenic AA
268
what is the term used to describe persistently high blood glucose
hyperglycemia
269
what fasted blood glucose level constitutes diabetic
>126 mg/dL
270
what are the symptoms of diabetes
frequent urination, dehydration and extreme thirst
271
what molecules accumulate as a result of long-term high blood sugar
ADVANCED GLYCATION END PRODUCTS (AGEs)
272
what types of food can lead to excessive amounts of AGEs in the blood
fried food
273
what can AGEs lead to an increase in
oxidative stress
274
what can we do to reduce the concentration of AGEs in our body
exercise to reduce the body's ability to synthesize AGE receptors
eat dark berries (antioxidants)
