Biochem Flashcards
1
Q
the Rer pumps out generalized proteins, the … makes proteins specialized
A
golgi
2
Q
smooth Er, … production in the adrenal cortex
A
steroid
3
Q
mitochondria has … passed on by mother
A
double membrane layer
4
Q
strongest bond?
A
covalent
5
Q
examples of noncovalent bonds
A
electrostatic
hydrogen
van der waals
6
Q
aspartate can be broken down into
A
oxaloacetate
7
Q
what is tyrosine made from
A
phenylalanine
8
Q
what can be made from tyrosine
A
dopa
epi
norepi
melanin
9
Q
amino acids have a … group which lipids and carbs do not have
A
nitrogen
10
Q
what is the precursor of serotonin?
A
tryptophan
11
Q
decarboxylation of histidine leads to which vasodilator?
A
histamine
12
Q
when the length of a polypeptide becomes very larger, > 100 AAs, the structure is termed a
A
protein
13
Q
glutamate is a precursor of
A
GABA
14
Q
… is a group of genetic disorders characterized by mutations in the enzyme tyrosinase which is necessary for the conversion of tyrosine to melanin
A
albinism
15
Q
the primary structure level of aa’s is the order of aa’s and this determines it’s…
A
function
16
Q
secondary structure level refers to local (non-covalent) interactions between neighboring amino acids, examples are ….
A
alpha helices
beta sheets
random coils
17
Q
tertiary structure level refers to a polypeptide chain folding on itself creating a 3D shape that is often stabilized by … bonds. 2 examples of a tertiary structure are…
A
covalent disulfide
globular
fibrous
18
Q
is a globular structure water soluble or insoluble?
A
soluble
19
Q
whats an example of a globular structure protein?
A
albumin
20
Q
is a fibrous structure protein water soluble or insoluble?
A
insoluble
21
Q
fibrous structures are most often involved in protection and maintaining cell/tissue structure and include …, …, and …
A
collagen
keratin
elastin
22
Q
collagen is …. +
A
glycine+x+y
23
Q
w/in the globular shape of a protein, which aa’s will you find
A
leucine
valine
24
Q
x-ray diffraction is the best way to analyze which structural level of a protein?
A
tertiary
25
... are proteins that serve as catalysts by lowering the activation energy needed to initiate a rxn
enzymes
26
.... bind to enzymes
substrates
27
IgM is ....
Made first. first antibody made in response to antigen
28
.... are highly specific y-shaped proteins produced by plasma cells in response to an antigen
antibodies
29
plasma cells are
mature B lymphocytes
30
.... is the most plentiful Ab in circulation, only one that can cross the placenta and is predominant Ab in gingivitis
IgG
31
... is the primary antibody in excretions such as mucous, saliva, tears, and breast milk. causes bacterial aggregation on mucosal surfaces
IgA
32
IgA causes bacterial .... but causes pathogens to not be able to ....
aggregation
adhere
33
IgE is the prominent antibody in what type of hypersensitivity rxn?
type 1
34
IgE binds to allergens and triggers ... release from .. cells
histamine
mast
35
histamine is found in which 2 types of cells
mast cells
| basophils
36
.... leads to histamine release
calcium depolarization
37
what are the symptoms of first exposure in a type 1 hypersensitivity rxn
no symptoms on first exposure but IgE antibodies are released and they bind to mast cells and basophils
38
is collagen water soluble or insoluble
water insoluble
39
... is the most abundant protein in the body
collagen
40
collagen consists of ... polypeptide strands stabilized by ... bonds that are eventually wound into a ...
3
disulfide
triple helix
41
each polypeptide strand of collagen consists of ....
Glycine+x+y
***Proline and lysine are commonly in the X and Y positions***
42
what are the 3 cofactors that are important for hydroxylation of proline residues during collagen synthesis?
vitamin C
ferrous ions
a-ketoglutarate
43
vitamin C deficiency causes
scurvy
44
symptoms of scurvy
bleeding gums
weakened connective tissue
poor wound healing
45
... and ... are autoimmune disorders that develop when the body attacks healthy collagen fibers
systemic lupus erythematous
rheumatoid arthritis
46
Lupus attacks .... and it occurs in .... and a distinct feature is...
DNA
young females
malar rash
47
the concentration of ... may be used as an estimate of the amount of collagen present within a given tissue
hydroxyproline
48
... results from an AD genetic defect in production of type 1 collagen, causing weak bones and connective tissue. common signs include multiple fractures, poor wound healing, and blue sclera.
osteogenesis imperfecta
49
.... results from a mutation causing abnormal synthesis, structure and secretion of type 1 and type 3 collagen. signs include loose and hyperextended joints, hyperelastic skin, and aortic dissection.
Ehler's Danlos syndrome
50
Elastin fibers are much more elastic than collagen because they do not contain ...
hydroxyproline
51
on hemoglobin: what state must iron be in for binding to occur?
ferrous or reduced state (fe2+)
52
.... comprise 90% of enamel proteins and are involved in the organization of enamel rods during development
amelogenins
53
what 3 things could cause thin hypoplastic enamel ?
amelogensis imperfecta
def. of vit A
def. of vit D
54
when you have a competitive inhibitor, then binding affinity .... and Km....
and the michaelis-menten graph moves to the ...
decreases
increases
right
55
when you have a noncompetitive inhibtor, vmax...and Km will be...
and the michaelis-menten graph is shifted...
decreases
unchanged
down
56
non competitive inhibtion will show an .... movement on the lineweaver-burke plot as ... decreases
upward
vmax
57
on the lineweaver-burke plot, remember that competitive...
crosses
58
... ligands bind to an allosteric site away from the active site of the enzyme that binds to the substrate
allosteric
59
example of an allosteric ligand?
ATP
60
a reaction will proceed spontaneously if it is an ..... rxn that results in a high degree of .... resulting in a ...
exothermic (-H)
randomness (large S)
-G
61
although G (in gibbs free energy eqn) provides info regarding the .... it does NOT provide info regarding the ...
direction of reaction
rate of reaction
62
which thermodynamic measures is a measure of randomness?
S = entropy
63
when something is oxidized it .... electrons
loses
| its an oxidized substance aka a reducing agent
64
when something is reduced it .... electrons
gains
| it is a redued substance aka an oxidizing agent
65
NADH/FADH are electron .... so they act as ... agents.
carriers
reducing
66
when NADH/FADH are oxidized, they become NAD+ and FAD+ and are important for producing ... via the ...
ATP
krebs cycle
67
NADPH is an... that is involved in the synthesis of biological molecules. it comes from the ...
electron carrier
pentose phosphate shunt
68
what is the formal definition of pH
-log [H+}
69
pH + pOH =
so 10^-5 + ? = 14
14
that means pH is 5 so pOH is 9
70
what is the buffer when H+ ions are released in the cell?
dihydrogen phosphate
71
what is the buffer when H+ ions are released outside the cell (plasma/blood)
carbonic acid
72
proteins are capable of buffering solutions over a wide range of pH because ...?
they contain many functional groups with different pKa values
73
according to the henderson-hasselbach equation, pH=pka when?
the acid is half neutralized
74
bacterial glycolysis is ... and produces .... which is ....
anaerobic
lactic acid
cariogenic
75
... is the most common type of bacterial glycolysis that is used by anaerobic
embden-meyerhof pathway
76
transamination means
breakdown of proteins for ATP
77
nitrogen balance refers to the ratio between .... versus
nitrogen absorbed
nitrogen excreted by body
78
if nitrogen catabolism exceeds the amount of aa'a ingested in the diet, the body has a negative nitrogen balance, this happens in ....
if aa synthesis exceeds nitrogen excretion, the body hase a positive nitrogen balance, this happens in....
anorexia and other wasting diseases
growth spurts and pregnancy
79
hydrolysis of sucrose yields what?
fructose
80
disaccharides are 2 monosaccharides joined by a ...
covalent O-glycosidic bond
81
what are the disaccharide forms
diehard MLS fan
maltose
lactose
sucrose
82
what is maltose made of
2 glucose
83
what is lactose made of
glucose + galactose
84
what is sucrose made of
glucose + fructose
85
monosaccharides are absorbed by.... in the small intestine
enterocytes
86
what are the 6 glycosaminoglycans (GAGs)?
```
chondroitin sulfate *main one
hyaluronic acid
heparin sulfate
heparin
keratan sulfate
dermatan sulfate
```
87
GAGs are polysaccharides made up of repeating ... they are ... charged and strongly attracted to...
disaccharide units
negatively
H2O
88
GAGs exhibit high ... and low... and are thus ideal for joint lubrication
viscosity
compressibility
89
why are proteoglycans able to attract water?
large number of alcohol groups
90
digestion is initiated in the saliva by ... for ... and .... for ...
amylase
starch
lipase
lipids
91
main buffer in saliva?
bicarb
92
main antibody in saliva?
IgA
93
what gland produces 75% of salivary secretions?
submandibular gland
94
caries activity is determined by
pH lower than 5.5
| and frequency of sugar contact
95
the first rxn of the krebs cycle involves the production of citric acid from.... and ... via the enzyme...
aceyl coa
oxaloacetate
citrate synthase
96
the first step of glycolysis involves the conversion of glucose to ... via the enzyme...
glucose-6-phosphate
glucokinase
97
in glycolysis, glucose is converted to .... and then into ... if oxygen is present or .... if oxygen is not present
pyruvate
acetyl coa which then enters the krebs cycle
lactic acid which is transported to the liver
98
... is the rate limiting enzyme of the glycolytic pathway
phosphofructokinase
99
glycolysis results in a net gain of .... and ... per glucose molecule
2 ATP
2 NADH
100
fluoride inhibits ...., an important enzyme near the end of the glycolytic pathway in bacteria
enolase
101
the cell gains a net total of .... per gluccose molecule during anaerobic respiration
2 ATP
102
the conversion of pyruvate to acetyl coa occurs in the .... by the enzyme ....
this reaction generates ... per pyruvate, for a total of .... per unit of glucose
cytoplasm
pyruvate dehydrogenase
1 NADH
2 NADH
103
where does the krebs cycle occur
mitochondrial matrix
104
low levels of citrate synthase may occur during .... or .... resulting in inability to produce ... from... so instead ... is converted to ....
starvation
diabetes
citric acid
acetyl coa
acetyl coa
ketone bodies
105
each TCA/krebs cycle produces ... and .... per molecule of acetyl coa but because 2 moleculs of acetyl coa enter the krebs cycle per molecule of glucose, the net gain is .... and ....
3 NADH
1 FADH2
6 NADH
2 FADH2
106
for acetyl coa to transport into the mitochondria, it needs ...
the pyruvate dehydrogenase complex
107
3 enzymes that make up the pyruvate dehydrogenase complex are
CoA
NAD
thiamine
108
pyruvate can be broken down into ... which will then produce a fatty acid
malonyl coA
109
3 things that can be used in the liver for gluconeogenesis
Lactate
Aamino acids
Glycerol
110
can acetyl coa be used for gluconeogenesis?
NO
111
glycogenesis happens in the
liver
112
the brain can use ... for energy if it doesnt have glucose
ketone bodies
113
what source does the body use for energy after 60 minutes of working out
lipids
114
what type of molecule is made from polyunsaturated fatty acids?
prostaglandins
115
are triglycerides part of the cell membrane?
no
116
... is the primary source of arachidonic acid
phosphatidyl inositol
117
phosphatidyl inositol is converted to arachiodonic acid through what enzyme?
and what drug can block that enzyme?
PLA2
steroids
118
arachiodonic acid can be converted to .... or ..... and ....
leukotrienes
prostaglandins
thromboxanes
119
... is a specific phospholipid that serves as an important structural component of nerve cell membranes and is the major component of the myelin sheath
sphingomyelins
120
arachiodonic acid is produced from .... and released from .... by the enzyme ... and serves as a precursor for .... that are produced by these 2 pathways
linoleic acid
phospholipids
phospholipase A
eicosanoids
cyclooxygenase pathway
lipooxygenase pathway
121
the cyclooxygenase pathway produces... which protects the stomach and .... which promotes platelet aggregation
prostaglandins
| thromboxane
122
the lipooxygenase pathway produces... which promote inflammation and play a role in allergic rxns (asthma)
leukotrienes
123
NSAIDS block ... which can lead to ulcers
cyclooxygenase pathway
124
linoleic acid is a ..... fatty acid
polyunsaturate omega 6
125
a mixed micelle is made up of ...
bile salts
free fatty acids
monosaccharides
126
... breaks down triglycerides into mixed micelles
pancreatic lipase
127
.... interactions help to maintain the structure of mixed micelles
hydrophobic
128
normal values for LDL, HDL, total cholesterol and triglycerides
LDL < 100
HDL>50
total cholesterol<200
triglycerides<150
129
#1 cause of xanthelasma?
aging
130
.... are yellow sharply demarcated cholesterol deposits found under the periorbital skin
xanthelasma
131
once LDL reaches its target tissue, it is transported into the cell via...
receptor mediated endocytosis
132
why is HDL good?
takes excess cholesterol from the organs to the liver
133
beta oxidation is the breakdown of .... and it produces what 3 things?
fatty acids
acetyl coa
NADH
FADH2
134
ketone bodies are used as the main source of energy during periods of fasting, what are the 3 main ones?
acetoacetate
acetone
beta-hydroxybutyrate
135
fatty acids are produced in a four step process.... that is repeated 4x
condensation
reduction
dehydration
reduction
**both reduction steps utilize NADPH as a reducing agent**
136
acetyl coA is converted to malonyl coa (fatty acids) via the enzyme...
acetyl coa carboxylase
137
is omega 3 anti or pro inflammatory
anti-inflammatory
138
omega 3 include ..., ... and ...
alpha-lenolenic acid
EPA
DHA
139
is omega 6 anti or pro inflammatory
pro inflammatory
140
omega 6 includes
alpha-lenoleic acid
| arach. acid
141
how many calories/gram for carbs, proteins and lipids?
4
4
9 lipids
142
which vitamins are fat soluble
DEAK
143
most toxic fat soluble vitamin?
D
144
sunlight converts .... in the skin to vitamin D
cholesterol
145
vitamin D becomes active in the
kidneys
146
function of vitamin D?
increases intestinal absorption of calcium and phosphate
promotes hardening of bones and teeth
147
a deficiency of vit. D can cause ... in children and ... in adults
ricketts
osteomalacia
(body tries to maintain calcium levels by leaching it from the bone making them softer or brittle)
148
excess vitamin D can result in...
| which is usually more common in?
sarcoidosis
middle aged african american females
149
which are the main vitamins that are antioxidants?
A C E + zinc
150
what is the precursor of vitamin A?
beta carotene
151
functions of vitamin A
```
epithelial tissue
enamel
rhodopsin
antioxidant
bone remodeling
```
152
deficiency of vit. A causes
night blindness
dryness of skin and eyes
enamel irregularities
153
... is a vitamin K antagonist
warfarin
154
vitamin K deficiency is most common in
newborns
155
deficiency of vitamin B1 (thiamine) may be associated with...
alcoholism (wernicke-korsakoff syndrome)
156
.... is an autoimmune disorder that destroys parietal cells of the stomach, causing a loss of production of intrinsic factor necessary for vitamin B12 absorption
pernicious anemia
157
what vitamin deficiency is most common worldwide
vitamin b12
158
you need .... which is produced by .... to absorb vitamin B12
intrinsic factor
parietal cells
159
is vitamin b12 deficiency associated with alcoholism?
yes
160
vitamin C is necessary for hydroxylation of ...
proline and lysine residues
161
vitamin is a cofactor in ... synthesis
collagen
162
deficiency of vitamin C leads to ... which results in ...
scurvy
delayed wound healing, rotting of teeth and gums, spontaneous hemorrhaging
163
..... aids in the synthesis of purines and pyrimidine nucleotides required for DNA synthesis
folic acid
164
most common vitamin deficiency in the US?
folate deficiency
165
folate deficiency can result in ...
spina bifida
166
what disease results from too much copper
Wilson's disease
| hepatolenticular degeneration
167
fluoride inhibits ...
bacterial enolase which is a key enzyme in glycolysis
168
fluoride converts ... to ... reducing enamel solubility and reversing or stopping caries formation
hydroxyapatite
fluoroapatite
169
... is critical for thyroid function as it serves as a component of thyroid hormones (T3 and T4). helps to regulate energy metabolism
iodine
170
what are T3, T4 and TSH levels in hyperthyroidism
T3 and T4 are high
| TSH is low
171
iron deficiency results in ... in children and .. in adults
cretinism
myxedema
172
iron is most commonly bound to ... in blood plasma
transferrin
173
functions of zinc
- antioxidant
- required for DNA synthesis
- cofactor for carbonic anhydrase
174
zinc serves as a cofactor for carbonic anhydrase, the enzyme responsible for converting .... and .... to ....
CO2 and H2O
bicarb
175
.... are responsible for eliminating free radicals and thus help to protect cells from oxidative stress
antioxidants
176
```
vit. A,C,E
zinc
gluthathione peroxidase
flavonoids/carotenoids
are all
```
antioxidants
177
A and T are bonded by
2 hydrogen bonds
178
G and C are bonded by
3 hydrogen bonds
179
nucleotides are linked together by ..... bonds between the 5' phosphate group and 3' OH group of neighboring sugar molecules
covalent phosphodiesterase bonds
180
what increases melting temp, more G/C bonds or more A/T bonds
G/C bonds
181
what are the base pairs for RNA
A/U (instead of A/T in DNA)
G/C
182
DNA strands wrap around .... proteins to form nucleosomes.
.... proteins contain high concentrations of lysine and arginine, basic and positively charged amino acids that bind tightly to negatively charged phosphate groups within DNA
histones
183
histone proteins contain high concentrations of
lysine and arginine
184
what is the function of histones
stabilize DNA in compact form
185
... connects DNA fragments on the lagging strand
DNA ligase
186
.... unwinds the parent DNA in an ATP dependent manner
helicase
187
... synthesizes primers , which are short sequences of RNA on the parent DNA strand that will serve as an initiation site for DNA polymerase
Primases (RNA polymerase)
188
.... extends the new DNA strand from 5' to 3' and helps to proofread base pairs in the newly synthesized strand. .... CANNOT start de novo, must have a primer to initiate
DNA polymerase
189
purine ribonucleoside phosphates are all synthesized de novo from which common intermediate
inosine phosphate
190
what enzyme catalyzes the formation of uric acid from purines
xanthine oxidase
191
transcription is
| translation is
DNA to RNA
RNA to proteins
192
... is coding RNA that serves as a blueprint for a specific amino acid sequence
mRNA
193
... is a cloverleaf shape RNA that matches the genetic information from an mRNA strand to specific amino acids
tRNA
194
.... assembles with proteins to form ribosomes necessary for protein synthesis
rRNA
195
RNA is copied into complimentary DNA by
reverse transcriptase
196
DNA that is complimentary to mRNA can be made by
reverse transcriptase
197
DNA damage by UV light is due to
induction of dimerization by way of covalent bonds between adjacent thymine groups
198
what is produced when a mutation occurs in an enzyme controlling a signal pathway involved in cell growth processes
oncogene
199
DNA replication, translation, or protein synthesis happen in all phases of the cell cycle except
M phase
200
when to use the different blot tests
Sunny Day- Southern DNA
No Rain- Northern RNA
Warm Picnic- Western protein
201
the isoelectric point is the pH at which a given molecule has ...
no net charge and will not move
202
if pH is lower that the isoelectric point of a protein, which way will the protein migrate
toward negative pole
203
if pH is higher than the isoelectric point of a proteins, which way will the protein migrate
toward positive pole
