Tooth/mouth, proteins/amino acids Flashcards
(297 cards)
1
Q
the organic matrix of enamel is made from noncollagenous proteins only and contains several enamel proteins and enzymes. t/f
A
true
2
Q
of the enamel proteins 90% are a heterogenous group of low molecular weight proteins known as amelogenins. T/F
A
true
3
Q
does enamel contain collage
A
no
4
Q
90% of enamel proteins are amelogenins. the other 10% are
A
enamelin and ameloblastin
5
Q
amelogenins are Hydrophobic or hydrophillic
A
hydrophobic
6
Q
amelogenins are rich in which a.acids
A
proline, histidine, and glutamine
7
Q
expression of amelogenins stops when the enamel
A
reaches full thickness
8
Q
loss of function of amelogenins will lead to
A
a thin hypoplastic enamel layer formed that lacks enamel rods
9
Q
ameloblastin is a protein mostly found in _ enamel and more on the outer surface than in deeper areas closest to the DEJ
A
newly formed (secretory stage)
10
Q
the largest and least abundant protein in enamel matrix
A
enamelin
11
Q
enamelin is only present at the
A
growing enamel surface
12
Q
ameloblasts produce enamel matrix (organic matrix) with protein components called
A
amelogenins and enamelins
13
Q
organic matrix makes up about _% of enamel
A
1-2%
14
Q
enamel has _% inorganic matter
A
95%
15
Q
enamel has _% water
A
4%
16
Q
is enamel permeable?
A
semipermeable
17
Q
enamel allows fluoride ions to be absorbed on the hydroxyapatite crystals, forming __ via __
A
fluorapatite via F- displacing the OH- groups
18
Q
fluorapatite makes tooth more
A
resistant to bacteria producing acids
19
Q
why does fluorapatite makes tooth more resistant to bacteria producing acids
A
because fluorapatite has a LOWER SOLUBILITY product constant than hydroxyapatite.
20
Q
which has higher solubility
fluorapatite or hydroxyapatite.
A
hydroxyapatite
21
Q
is enamel harder than bone?
A
yes
22
Q
why is enamel harder than bone?
A
because hydroxyapatite crystals are larger and more firmly packed.
23
Q
the hydroxyapatite crystals are __ shaped rods called __
A
keyhole shaped rods called enamel prisms
24
Q
the hydroxyapatite crystals in enamels are _ times larger than those in bone, dentin and cementum
A
4x
25
enamel hypoplasia is the defect in the
a. mineralization of enamel matrix
b. formation of the enamel matrix
formation of the enamel matrix
| not a defect in the mineralization of the formed enamel matrix
26
enamel hypoplasia is a general term to all __ defects of enamel thickness
quantitiative
| pits, small furrows, troughs of missing enamel
27
hypocalcification and opacities are _defects
qualitative
28
hypoplasia occurs only if the assault occurs when?
during the time the teeth are developing. either primary/permanent
29
in hypoplasia how do the teeth look? color?
pitted, yellow to dark brown color and have open contacts
30
hypoplasia appears _ on radiograph
enamel appears to be absent or very thin, especially over the cusp tips and interproximally
31
in hypoplasia, the enamel is hard/soft? thin/thick?
hard but thin and deficient in amount
32
hypoplasia causes
hereditary or environmental
33
environmental causes of hypoplasia
vitamin A and D deficiency, inadequate calcium intake, fluorosis, congenital syphilis, high fever, injury or trauma to the mouth
34
Enamel hypocalcification is a defect in _ of the _
mineralization of the formed enamel matrix
35
enamel hypoplasia is a defect in the _
formation of the enamel matrix
36
tooth __ in bulimic patients is due to the solubility of hydroxyapatite in acid
erosion
37
enamel hypoplasia/hypocalcification is strongly associated with amelogenesis imperfecta
hypoplasia
38
caries activity is directly proportional to the quantity of fermentable carbs ingested. t/f
false.
39
the enzyme __ produced by strep mutans is the key factor in demineralizing tooth surfaces that leads to caries
glucosyltransferase
40
glucosyltransferase is aka
dextran sucrase
41
the most frequently isolated strep in the oral cavity is
s. sanguis
42
name 3 bacteria in mouth that produce glucosyltransferase
s. mutans
s. sanguis
lactobacillus
43
glucosyltransferase catalyzes the formation of _ from _
extracellular glucans from sucrose
44
glucan production contributes to the
formation of plaque
45
the dental plaque holds the _ against the tooth
lactic acid
46
caries depends on the balance bw
remineralization and demineralization
47
the primary physiological control of the salivary gland is by the _ nervous system
parasympathetic
48
control of salivary secretion is exclusively neural. T/F
true
49
functions of saliva
lubricate and moisten food for swallowing
solubilization of material for tase
initiate carb digestion
clearance and neutralization of refluxed gastric secretions in the esophagus
antibacterial
50
how many major salivary glands
3 = parotid submandibular sublingual
51
many other smaller glands are found on the
tongue, lips, and palate
52
the acinar portion of the gland is classified according to its major secretion: mucous mixed or serous. the parotid produces mainly
serous secretion
53
the sublingual produces mainly _ secretion
mucous (think under your tongue you have mucous)
54
submandibular gland produces _
mixed secretion
55
mucous secretions contain
mucins = glycoproteins = proteins with polysaccharides that lubricate the food
56
serous secretions contains ___
salivary amylase (ptyalin).
57
ptyalin splits starch into
alpha-dextrin, maltotriose and maltose (think MaD'M)
58
pns nerves stimulating the salivary gland will __ blood flow by ___ the vasculature of the glands
increase blood flow
| dilating
59
__ and __ are released from the PNS nerve terminals in the salivary glands.
vasoactive intestinal polypeptide (VIP) and acetylcholine (AcH)
60
PNS stimulation of the salivary glands releases vasoactive intestinal polypeptide (VIP) and acetylcholine (AcH). these 2 will cause vasodilation/vasoconstriction of the glands
vasodilatory during secretion
61
control of salivary secretion is exclusively
| neural/hormonal
neural
62
in contrast to salivary secretion, GI secretions are primarily
neural/hormonal
hormonal
63
salivary secretion is stimulated by SNS/PNS
BOTH
64
Sympathetic fibers to salivary glands stem from the
superior cervical ganglion
65
preganglionic PNS fibers travel via branches of the _ and _ nerves
facial (VII) and glossopharyngeal nerves
66
parasympathetic fibers form synapses with postganglionic neurons in
ganglia in or near the salivary glands
67
vagal stimulation __ saliva production
increases
68
vagotomy
is a surgical procedure that involves resection of the vagus nerve
69
vagotomy would have what effect on saliva production
inhibit saliva production = dry mouth
70
atropine effects on salivation?
atropine counters the "rest and digest" activity of glands regulated by the parasympathetic nervous system. This occurs because atropine is a competitive antagonist of the muscarinic acetylcholine receptors. Atropine dilates the pupils, increases heart rate, and reduces salivation and other secretions.
71
___ prevents the action of AcH on the secreting cells in the oral cavity
Atropine
72
Saliva has a low/high K+ concentration
high
73
saliva has low/high osmolarity
low
74
saliva is always hypotonic T/F
True
75
saliva inorganic composition is entirely dependent on the stimulus and rate of salivary flow. T/F
True
76
saliva has a large flow rate relative to the mass of the gland, low osmolarity, and high K+ concentration and organic constituents including enzymes (amylase, lipase), mucins, and growth factors. the INORGANIC composition is ENTIRELY DEPENDENT on the
stimulus and the rate of flow which is stimulated during a meal.
Na+, K+, HCO3-, Mg2+, Ca2+ Cl-
77
why is salvia always hypotonic in humans
ductal cells reabsord NaCl in exchange for potassium and bicarbonate
78
the organic constituents of saliva, proteins, and glycoproteins are synthesized and stored and secreted by
acinar cells
79
the major organic products are
amylase lipase glycoprotein lysozyme
80
glycoproteins are mucins which form _ when hydrated
mucous
81
lysozymes in saliva will
attack bacterial cell walls to limit colonization of bacteria in the mouth
82
saliva acts as a buffer. caries can be modified by
saliva
83
the balance bw remineralization and demineralization can be altered substantially by the
rate of salivary flow
84
a maximum salivary flow rate of __associated with a HIGH caries risk
<0.7mL/min
85
the essential amino acids we
need from diet
86
non essential amino acids are synthesized from common metabolic intermediates or from
other amino acids
87
only amino acids that are exclusively ketogenic
leucine and lysine
88
ketogenic amino acid means
cant be made into glucose.
| they are broken down into acetyl coA or acetoacetate
89
glucogenic amino acids means
can enter gluconeogenesis. broken down into pyruvate or 4 or 5C intermediates of TCA
90
how many of the 20 amino acids can be synthesized in the human body? Is that essential or non essential
non essential = 11
91
amino acids are used for what 3 purposes
1. generation of metabolic energy
2. protein synthesis
3. synthesis of many products ex. heme, purine, pyrimidines, coenzymes, melanin, biogenic amines
92
amino acids broken down into pyruvate _ and what else are glucogenic
```
alpha ketoglutarate
succinyl coA
fumarate
OAA
can convert to glucose and glycogen
```
93
the nitrogen of the amino acids is incorporated into _
urea
94
is urea soluble? toxic?
soluble and not toxic. excreted in urine
95
in eukaryotes DNA does not exist free. it is complexed w/an equal mass of BASIC proteins called
histones
96
histones contain a large portion of what 2 amino acids?
arginine and lysine
| remember your mnemonic: HRK = + charged basic amino acids = H = histidine, R = arginine, K = lysine
97
each chromosome is a _ molecule of DNA complexed with an equal mass of proteins
single
98
DNA and proteins are called __ collectively
chromatin
99
most of protein in DNA consists of
copied of 5 kinds of histones: H1, H2A, H3, H4
100
both arginine and lysine have a _ on their R group
free amino group which attracts protons giving them a positive charge = therefore perfect to bind tightly to negatively charged phosphate groups of DNA
101
histones help to
neutralize the large negative charge of the DNA phosphate groups and stabilize DNA in a COMPACT form
102
histones package and order the DNA into structural units called
nucleosomes
103
nucleosomes are
repeating subunits of chromatin consisting of a DNA coiled around a core of histones
104
chromatin also contains non histone proteins. most of these are
transcription factors and their association with DNA is more transient
105
activation of DNA for replication or transcription requires
breakup of the nucleosome structure
106
phosphorylation of _ and _ residues in histones is part of the process for replication
serine and threonine
107
acetylation of lysine residues in the histones is used for __
transcriptional activation
108
proteins are formed by the reaction bw
alpha amino group of one a.a. and an alpha carboxyl group of another amino acid
109
how many proteins (peptides) in a chain to be called a polypeptide chain?
10 or more
110
a protein is a polypeptide chain of _ or more amino acids linked together
100 or more
111
a disulfide bond is a covalent/non covalent bond
covalent
112
what 2 amino acids form a disulfide residue
cysteine
113
2 or more polypeptide chains are called
subunits
114
2 subunits associate via covalent/non covalent bonds
non covalent
115
quaternary structure formed via
disulfide bonds
116
Examples of proteins with quaternary structure include?
hemoglobin, DNA polymerase, and ion channels.
117
most plasma proteins are derived from
liver
118
__ are the only proteins NOT produced by the liver
immunoglobulins
119
immunoglobulins are made by
plasma cells
120
most plasma proteins are __
glycoproteins.
121
the only plasma protein that is not a glycoprotein is
albumen
122
plasma proteins circulate for several days and are eventually removed from circulation when
their oligosaccharide chains are worn down
123
60% of plasma proteins are
albumen
124
albumin accounts for 60% of all plasma proteins and __% of the colloid osmotic pressure of plasma
80%
125
why does albumen account for more than 60% of the colloid osmotic pressure?
bc colloid pressure depends on the amount of water and electrolytes that a protein attract to its surface and albumin is one of the most hydrophilic plasma proteins
126
edema develops when the albumin concentration drops below
2g/dL
127
globulins are/are not soluble in:
1. salt solution
2. pure water
1. soluble in salt solution
| 2. not pure water
128
globulins make up 35% of plasma proteins and are used in the
transport of ions, hormones, and lipids
129
fibrinogen accounts for _% of plasma protein
4
130
fibrinogen/fibrin is insoluble?
fibrin. fibrinogen can be converted to fibrin
131
regulatory proteins make up _% of plasma
<1% = proteins such as enzymes, proenzymes, and hormones
132
intracellular proteins absorb _
hydrogen ions generated by the body's metabolic processes
133
lipoproteins are plasma proteins. name the lipoproteins
chylomicrons, VLDL, LDL, HDL
134
transferrin is another plasma protein used for
iron transport
135
prothrombin is a plasma protein involved in
blood clotting
136
what is the molecule called that is formed by the condensation of 2 proteins
amide
137
bonds involving the alpha carbon can or cannot rotate freely in peptide bond
can
138
do the alpha amino or alpha carboxyl group in peptide bond give off protons?
no. therefore they don't ionize at physiological pH
139
peptide bonds can or cannot be cleaved by organic solvents or urea
cannot
140
peptide bonds are susceptible to
strong acids
141
peptide bonds are generally trans/cis
trans
142
peptide bonds are charged? polar?
uncharged and polar
143
__ due to formation of a tertiary amine restricts the range of rotation of the alpha carbon in a peptide bond
proline
144
disulfide bond is formed by the _ group of 2 cysteines
sulfhydryl (SH)
145
two sulfhydryl groups on 2 cysteines will form a _ residue
cystine residue (NOT CYSTEINE)
146
___ is a constituent of collagen and RARELY FOUND IN ANY OTHER PROTEIN
hydroxyproline
147
hydroxyproline in collagen function
stability to the triple helical structure via H bonding
148
vitamin C is required for what step in collagen synthesis
hydroxylation of proline.
149
_ is the only non chiral amino acid
glycine (not optically active)
150
myoglobin consists of _ polypeptide with a non covalently bound heme group
single
151
hemoglobin has _ polypeptides each with its own heme
4
152
1. myoglobin has _ polyptides vs hemoglobin's _
1 vs 4
153
why do humans need oxygen binding proteins?
because molecular O2 is poorly soluble in body fluids
154
both myoglobin and hemoglobin use heme as a _ group
prosthetic
155
adult hemoglobin has 2 _ chains and 2 _ chains
alpha and 2 beta
156
adult hemoglobin abbreviation is
HbA (A for adult)
157
fetal hemoglobin abbreviation is
HbF (F for fetal)
158
fetal hemoglobin has 2 _ chains and 2 _ chains
2 alpha and 2 gamma
159
both HgA and HgF have _ chains.
2 alpha
160
The difference bw the polypeptide chains of HgF and HgA is
HgF has 2 delta chains
| HgA has 2 beta chains
161
myoglobin has a __ oxygen binding affinity than all the hemoglobins
FAR HIGHER
162
HbF has a __ affinity than HbA
slightly higher
163
which has higher affinity for oxygen: myoglobin or fetal Hb
myoglobin higher than ALL hemoglobins
164
__ is a MONOMERIC HEME PROTEIN
myoglobin = it contains only one heme protein
165
__ serves as an intracellular oxygen storage site in muscle tissue.
myoglobin
166
oxymyoglobin releases oxygen in times of oxygen deprivation. it is aka
muscle hemoglobin
167
muscle hemoglobin refers to oxyhemoglobin or deoxyhemoglobin?
oxyhemoglobin (myoglobin with oxygen)
168
myoglobin is located within muscle cells or between cells
WITHIN
169
which stores oxygen more efficiently myoglobin or Hg
myoglobin binds and stores more efficiently
170
myoglobin and Hg are _ proteins
specialized
171
the heme iron in Hg and Myoglobin binds O2 oxygen in what state
ferrous Fe2+
172
if Fe2+ is oxidated to Fe3+ then it is called __
ferric
173
ferric iron is found in
methemoglobin.
174
the enzyme ___ reduces methemoglobin back to normal Hg using coenzyme _ as the reductant
methemoglobin reductase, NADH
175
in contrast to Hg and Myoglobin where iron is always in _ state, the heme iron in cytochromes are
Hg and Myoglobin = Fe2+ ferrous
| cytochromes = switch back bw ferrous and ferric Fe3+
176
in almost all cytochromes the heme iron is bound to how many amino acid side chains? exception is which
2 amino acid side chains
cytochrome a/a3 is exception
177
the heme iron in cytochromes being bound to 2 amino acid chains rather than one (like in Hg and myoglobin) results in
molecular O2, CO, and other ligands not being able to bind the iron
178
cytochromes are membrane bound __
hemoproteins
179
cytochromes carry out
electron transport
180
cytochromes are found in the __ of euk, _ of plants, and _ bacteria
mitochondrial inner membrane and ER of eukaryotes, in the chloroplasts of plants, and in photosynthetic bacteria
181
electron transport and ATP synthesis by oxidative phosphorylation proceed continuously in all cells of the body that contain
mitochondria
182
cytochromes receive electrons from the _ form of which coenzyme?
reduced form of coenzyme Q (aka ubiquinone)
183
each cytochrome contains a heme group made of a _ containing a _
porphyrin ring containing an iron atom
184
the cytochrome iron atom is the _
electron carrier and is reduced when the cytochrome accepts an electron
185
cytochromes are distinguished by the differences in their __ which is a result of the heme prosthetic group
light absorption spectra
186
name the 5 cytochromes
b, c1, c, a3, a
187
which cytochromes are the terminal members of the e- transport chain
a3 and a
188
a3 and a exist as a complex called
COMPLEX IV or cytochrome oxidase complex
189
the prosthetic groups of cytochromes contain how many 5 membered rings called _
4 five membered rings that contain nitrogen = porphyrin
190
the 4 nitrogen in the porphryn rings coordinate with
a central Fe ion (Fe2+ or Fe3+)
191
these porphyrins are also found in (2)
heme proteins hemoglobin and cytochrome P450
192
what are the 2 precursors to the formation of the porphyrin ring?
glycine and succinyl-CoA
193
amino acids that lose their amino groups are converted into __ and ultimately enter __
alpha keto acids
| enter TCA cycle
194
pyruvic acid and oxaloacetic acid are both
keto acids (amino acids can enter here after losing their amino groups)
195
an alpha keto acid is similar to an amino acid except that it has a __ instead of the amino group bonded to its alpha carbon
oxygen
196
when proteins are broken down and used for energy most of this energy is derived from the oxidation of
keto acids = pyruvate, OAA and alph ketoglutarate
197
GABA) is made from which amino acid:
| glutamate or glutamine?
```
glutamate (E) = acid
not glutamine (Q)
```
198
what amino acid can be synthesized from ribose-5-phosphate
histidine
199
what amino acid can be directly synthesized from 3 phosphoglycerate
serine
200
what amino acid can be directly synthesized from OAA
aspartate (D)
201
what amino acid can be synthesized directly form alpha ketoglutarate
glutamate (E)
202
the 4 amino acids that can be synthesized from pyruvate are
```
Alanine
Valine
Leucine
Isoleucine
P-VAIL
```
203
PEP and erythrose-4-P make
shikimate
| only in plants and bacteria
204
shikimate is converted to
chorismate
| only in plants and bacteria
205
chorismate converted to
trypsinogen, tyrosine, phenylalanine (only in plants and bacteria)
206
glycine and serine can be made from
serine
207
proline arginine and glutamine can be made from
glutamate
208
threonine, lysine, asparagine and methionine can be made from
aspartate (D)
209
the 2 small amino acids are
glycine and alanine
210
the 3 branched amino acids
valine leucine isoleucine
211
hydroxyl amino acids (2)
serine and threonine
212
aromatic amino acids (3)
tryptophan tyrosine phenylalanine
213
sulfur amino acids (2)
methionine cysteine
214
basic amino acids
HRK = lysine histidine arginine
215
imino acid?
proline
216
acidic amino acids?
aspartate (D)
asparagine (N)
glutamate (E)
glutamine (Q)
```
DE are negatively charged, NQ are neutral
HRK DE-NQ WAM V PIGFLY
HRK = basic + charged
DE = acidic negative charged
NQ = acidic neutral
```
WAM V PIGFLY non polar non charged
217
elastin has a high proportion of which 3 amino acids:
valine, phenylalanine, lysine
tryptophan, histidine, methionine
glycine, alanine and proline
threonine, cysteine, and glutamate
glycine, alanine and proline
think GAP = elastin
gylycine (31%0, alanine (22%), and proline 11%
1% of hydroxyproline
218
does elastin have any hydoxylysine?
none
219
like collagen, elastin contains ___ that are derived from ___
covalent crosslinks,
| allysine
220
because both collagen and elastin have covalent crosslinks derived from allysine, they both have the enzyme
lysyl oxidase (LOX)
221
__ is required for the synthesis of elastin and collagen
lysyl oxidase (LOX)
222
the covalent crosslinks of elastin are similar to those of collagen except for __ which is present in elastin BUT NOT COLLAGEN
desmosine
223
1. desmosine is present in collagen/elastin?
| 2. lysyl oxidase (LOX) is present in collagen/elastin?
1. elastIN (look at desmosINe)
| 2. both
224
1. collegen forms fibers that are tough and have high __ strength.
2. elastin is CT protein with __ like properties
1. tensile
| 2. rubber
225
elastic fibers can be stretched to several times their normal length (it is the elastin that gives these fibers the capacity of returning to their original lengths after being stretched). these elastic fibers are found in
skin, ligaments and the walls of arteries.
226
the polypeptide subunit of elastin fibrils is
tropoelastin
227
the crosslinks in elastin involve __ and __
lysine and oxidized lysine residues (allysine) which are covalently linked to produce a desmosine cross link
228
where does the oxidation of lysine residues in both collagen and elastin occur?
extracellularly
229
oxidation of lysine residues in both collagen require what enzyme
lysyl oxidase
230
Lysyl oxidase requires what cofactor
copper
231
elastin is surrounded by
microfibrils
232
the most important microfibril protein fibrillin-1 is defective in ___ syndrome
Marfan syndrome
233
Marfan syndrome is a genetic disorder caused by the misfolding of the protein fibrillin-1. is known as a connective tissue disorder. Fibrillin-1 protein forms fibers in connective tissue.People with Marfan tend to be unusually tall, with long limbs and long, thin fingers. It is an autosomal ___ disorder,
dominant
meaning that people who inherit only one copy of the Marfan FBN1 gene from either parent will develop Marfan syndrome and be able to transmit it to their children
234
name the 3 amino acids that carry a positive charge and are basic
HRK
| histidine, arginine, lysine
235
hydrophobic (non polar) amino acids repel aqueous and therefore are found in the interior/exterior of proteins
inside
236
hydrophilic (polar) amino acids tend to interact with aq environment and found on the _ surface of proteins or in the reactive centers of enzymes
exterior
237
the functions of amino acids in proteins are determined by the
covalent and noncovalent interactions
238
__ a.acids occupy little space. I proteins they are found in places where 2 poplypeptide chains have to come close together
glycine and alanine (small amino acids)
239
branched chain amino acids have hydrophobic/hydrophilic side chains
phobic (valine leucine and isoleucine)
240
the hydroxyl amino acids _ and _ form hydrogen bons with their hydroxyl group
serine and threonine
241
sulfur amino acids like _ and _
cysteine and methionine -hydrophobic. except cysteine has weak acid prperties
242
the aromatic amino acids: _(3) are hydrophobic although the side chains of _ and _ can form h bonds
tyrosine, tryptophan, phenylalanine
tyrosine, tryptophan
243
which amino acids can form covalent bonds with carbs in glycoproteins and with phosphate in phosphoproteins
serine and methionine (sulfur)
244
the acidic amino acids (2) have side chains that are _ charged at pH 7
DE: glutamate and aspartate
245
which amino acid has its nitrogen tied into a ring
proline
246
what is the distinguishing factor in proteins
their amino acid sequence
247
the _ structure = seq of amino acids linked together by covalent peptide bonds
primary
248
the _ structure refers to the SPATIAL ARRANGEMENT of a portion of a polypeptide chain determined by the amino acids present (primary structure)
secondary
249
the most common types of 2ndary structure
alpha helix = coiled conformation of a peptide chain
beta pleated sheets - zigzag arrangement
beta hairpin turns (reverse turns)
250
the __ structure refers to the IRREGULAR folding of polypeptide chain, the overall 3D CONFORMATION of the polypeptide
teritary
251
the best method for determining the 3D structure of a protein is by
x-ray diffraction
252
the _structure refers to the spatial arrangement of SUBUNITS in a protein that consists of more than one polypeptide chain
quaternary
253
hemoglobin has _ structure
quaternary
254
antibody molecules have _ structure
quaternary
255
name 2 quaternary structures in the blood of mammals
hemoglobin
| antibody molecules
256
patients with vitamin C deficiency form a collagen with insufficient:
hydroxylysine
hydroxyproline?
hydroxyproline
257
patients with scurvy (Vit C def) will have collagen with insufficient hydroxyproline because it
denatures spontaneously at room temp
258
__ is a cofactor for enzymes that catalyze carboxyl-group-transfer reactions and ATP-dependent carboxylation reactions
Biotin
259
In collagen synthesis:
1. vitamin C is required to hydroxylate _
2. copper is required to hydroxylate _
1. Vit C = proline
| 2. Cu2+ = lysine
260
mnemonic for collagen types
```
SCAB:
type 1 = skin. rhymes with dentIN, tendon, and Type ONE = bONE
type 2 - ct, carTWOlidge
type 3 arteries
type 4 basement membrane
```
261
where do we hydroxylate proline and lysine in collagen synthesis
in the endoplasmic reticulum (ER)
262
what is the most abundant amino acid in collagen
glycine
263
Up to 30% of the total protein mass of body
| is
collagen
264
All types of collagen in our body are constructed from 3 __handed helical peptides twisted into a right-handed triple helix
left
265
which type of collagen found in dentin
type 1: (remember SCAB) = skin, dentIN, tendon, bone, cornea, ligament.
266
is collagen thicker or longer? heavy?
Collagen (Mr, 300 kda) is a rod-shaped molecule about 3000A long and only 15A thick.
267
each alpha chain of collagen has about _ # amino acids
1000 amino acids residues.
268
which of the following serves as a principal source of carbon for non essential amino acids
fats/water/carb/urea
carbs
269
10 of the nonessential amino acid skeletons can be derived from
glucose (glucogenic)
| VAL HAS THREE MEN IN PHX TUSCON = essential glucogenic, LOVING LIFE = ketogenic, ALL OTHERS ARE NON ESSENTIAL
270
is tyrosine essential or non essential
non essential
271
tyrosine is synthesized by the _ of what amino acid
hydroxylation of the essential amino acid phenylalanine
272
although cysteine's carbon skeleton can be formed from carbs, it requires which amino acid to supply the sulfhydryl group
methionine
273
1. non-essential amino acids can be synthesized from the corresponding alpha-keto acids, an alpha amino acid (NH3+ donor), a specific transaminase enzyme and ___
2. the 3 non essential amino acids that can do this are
```
phyridoxal phosphate (the coenzyme form of vitamin B6)
alanine aspartate glutamate
```
274
all other nonessential amino acids besides alanine glutamate and aspartate are synthesized by
amidation (glutamin and asparagine)
275
amino acids are degraded into
CO2, water and urea
276
because ammonia is toxic it must be converted to non toxic
urea in urea cycle
277
the urea cycle is only present in the
liver
278
carbon skeletons of amino acids are channeled into
gluconeogenesis (glucogenic amino acids) or ketogenesis (ketogenic amino acids)
279
a patient with phenylketonuria PKU cannot drink soda because it contains:
a. tyrosine she can't metabolize
b. phenylalanine which she is unable to metabolize
she can't metabolize phenylalanine
PKU = phenylalanine build up
280
what supplement would you expect a patient with PKU to be taking:
tyrosine or phenylalanine
tyrosine
remember: phenylalanine ==> tyrosine (you add a hydroxyl group) = remember alphabetical order p makes t
281
phenylalanine is an essential amino acid needed for
optimal growth in infants and for nitrogen equilibrium in adults
282
hydrophobic/hydrophilic amino acids have side chains that contain aliphatic groups and/or aromatic groups
hydrophobic
283
an aliphatic amino acid means
Aliphatic R groups are nonpolar and hydrophobic.
284
name the 3 aliphatic amino acids
valine leucine isoleucine
285
name the 3 aromatic amino acids
phenylalanine, tyrosine, tryptophan
286
dopamine, the thyroid hormones (t3 and t4), melanin, NE, and Epinephrine are all synthesized from what amino acid
tyrosine
| TMEND: thyroid, melanin, epinephrine, norepinephrine, dopamine
287
melanin is a natural substance that gives color (pigments) to the (3)
hair
skin
iris of eye
288
5-hydroxytryptamine aka
serotonin (5-HT)
289
5-hydroxytryptamine (serotonin), melatonin, niacin, nicotinamide moiety of NAD+ and NADP+ are formed from the essential amino acid ___
tryptophan
tryp = SMNN
290
mnemonic for things synthesized from tyrosine and tryptophan
```
tyrosine = MTEND
tryptophan = SMNN
```
291
phenylalanine hydroxylase is defected in which syndrome
PKU
292
when you have more nitrogen output than input you have _ nitrogen balance
negative
293
negative nitrogen balance may be caused by
dietary lack of essential amino acids
294
tyrosinase is absent in
albinism
295
tyrosinase catalyze the synthesis of
melanin
| tyrosine ==> melanin
296
do albinos have problems with epinephrine synthesis
no
297
In human blood, __ is the most abundant free amino acid
glutamine
| (Q or Gln) ==> 2 amine groups
