BECOM Exam #1 Flashcards
1
Q
Micelle
A
2-monoacyglycerol, cholesterol, and lysophospholipid that are emulsified with bile salts
2
Q
Chylomicron
A
- apolipidprotien B-48
- contains cholesteryl esters, triaclylglycerols, and phopholipids
3
Q
What does HDL do
A
- takes cholesterol from nonhepatic tissue to liver as cholesteryl ester
- apeE and apoCII reservoir (passes to chylomicron and VLDL)
4
Q
How does the body make cholesterol?
A
HMG-CoA pathway (2 carbon acyl units)
5
Q
What does apoE do?
A
is recognized by membrane receptors, particularly those on the surface of liver cells, allowing apoE-bearing lipoproteins to enter these cells by endocytosis for subsequent digestion by lysosomes
6
Q
What does apoCII do?
A
activator of lipoprotein lipase
7
Q
What does lipoprotein lipase do?
A
digest TAGs to glycerols and fatty acids
8
Q
What does 7-alpha hydrolase do?
A
- is the rate-limiting enzyme in the synthesis of bile acid from cholesterol
- mutation can cause low bile salt concentration
- adds -OH to seventh carbon of cholesterol
9
Q
Cholesterol is the precursor for?
A
bile salts, steroid hormones, and vitamin D
10
Q
What protein determines VLDL and LDL
A
B-100
11
Q
Phospholipase 1
A
hydrolysis cleaves at sn1 of phospholipids
12
Q
Phospholipase 2
A
hydrolysis cleaves at sn2 of phospholipids
13
Q
components of a nucleotide
A
phosphate, ribose sugar, and nitrogenous base
14
Q
Purine Biosynthesis starting with
A
a ribose sugar
15
Q
Allopurinol
A
competitive inhibitor of xanthine oxidase (hypoxanthine -> xanthine -> uric acid)
16
Q
Large amounts of uric acid causes?
A
Gout
17
Q
Adenine phosphoribosyltransferase (ARPT)
A
takes adenine + PRPP -> AMP (purine salvage pathway)
18
Q
Hypoxanthine - guanine phosphoribosyltransferase (HGPRT)
A
takes (hypoxanthine or guanine) + PRPP -> IMP or GMP
19
Q
Lesch - Nyhan Disease
A
Hypoxanthine - guanine phosphoribosyltransferase (HGPRT) deficiency (causes inc PRPP and no nucleotide salvage)
20
Q
PRPP usage?
A
- synthesis of purines and pyrimidines
- salvage purine and pyrimidines
- synthesis of NAD from tryptophan
21
Q
6-mercaptopurine
A
gets salvaged and inhibits enzymes in the purine biosynthesis pathway (chemotheuroputic)
22
Q
5-fluorouracil
A
gets salvaged and inhibits the pyrimidine biosynthesis pathway
23
Q
Pyrimidine biosynthesis starts with a?
A
base
24
Q
Hereditary Orotic Aciduria
A
lack enzyme in pyrimidine biosynthesis pathway (high orotic acid)
oral UMP
25
hexokinase
glucose -> glucose 6-phospate in glycolysis
26
hydrolase
A + H2O -> B + C
27
Oxidoreductase
catalyzes oxidation or reduction reactions
28
Lyase
cleaves C-C, C-S, or C-N bonds
29
Transferase
Ax + B -> A + Bx
30
Isomerase
two compounds with same formula but different arrangements
31
Ligase
A + B -> AB
32
Detoxification phase I
cytochrome P450
33
Detoxification Phase II
GSH conjugation, sulfation, glucuronidation
34
primary protein
covalent linked
35
secondary protein
H-bond
36
tertiary and quaternary protein
```
Multiple secondary
H bond
LDFs
Salt bridges
Disulfide
```
37
ubiquination added tag to which residue
lysine residue
38
N-glycosalation
aspirigine
39
reducing agents
break disulfide bonds
40
ferrous
+2
41
ferric
+3
42
Bohr effect
higher CO2 or decreased pH = decrease in O2 affinity
43
2,3 BPG
decreases Hb affinity for O2 (negatively charged and pulls positively charged subunits towards middle pushing out O2)
44
Haldane effect
high O2 concentration in lungs decreases affinity of Hb for CO2
45
HbA
alpha 2, beta 2
46
HbF
alpha 2, gamma 2
47
Hydroxyurea
induces HbF during sickle cell anemia that will reduce sickling because of hertero-tetramer
48
methemoglobin
heme trapped in the Fe3+ state (ferric)
49
carbon monoxide poisoning
CO binds to one subunit causing Hb to have a higher affinity for O2 resulting in a O2 trap
50
cholesterol is involved in?
steroid synthesis, membrane fluidity, vitamin D synthesis, and bile salt synthesis
51
Alpha amylase (mouth)
cleaves alpha 1,4 linkage producing dextrin
52
Pancreatic α-amylase (lumen of stomach)
cleaves α-1,4 linkages (Product: dissacharides (maltose, isomaltose), trisaccharides (maltotriose), oligosaccharides (limit dextrins))
53
Sucrase-isomaltase
splits sucrose, maltase, maltotriose, dextrins
| (hydrolyzes α-1,4 and α-1,6 linkages)
54
Lactase
hydrolyzes ß-1,4 bond of glucose and galactose
55
Sucrase
hydrolyzes α-1,2 bond of glucose and fructose
56
SGLT
small intestine and kidneys, reabsorption of glucose that has been tagged for excretion (diabetic drugs inhibit this)
57
GLUT1
red blood cells and cell with barrier functions (brain, retina, placenta, and testes)
58
GLUT2
Liver (storage when glucose higher) and pancreatic B cells (insulin secretion)
59
GLUT3
brain and neurons (high affinity for glucose)
60
GLUT4
skeletal muscles and adipose (go to surface when insulin present or when exercising)
61
GLUT5
fructose transporter in intestine luminal epithelium and sperm
62
Mutarotation
Change in the rotation of plane-polarized light resulting from the equilibrium between cyclic anomers and the open-chain form of a sugar (gluceoromator: oxidize open chain)
63
Purine free bases
adenine, guanine, hypoxanthine, and xanthine
64
Methotrexate
act as a competitive inhibitor to dihydrofolate reductase prevent the conversion of FH2 to FH4
65
Pyrimidine free bases
uracil, cytosine, and thymine
66
CPS II
- in cytosol
- uses Gln and CO2 to form carbamoyl phosphate (pyrimidine biosynthesis)
- inhibited by UTP, activated by PRPP
67
CPS I
in mitochondria, is used in the production of urea
68
Nitrogenous base
A U G T C
69
derivatives of purine
aspartate, N10 formyl FH4, glutamine, glycine, CO2
70
derivatives of pyrimidine
glutamine, aspartate, CO2
71
How is PRPP made
ribose 5-phosphate + ATP
72
Lesch-Nyhan Disease
Deficiency in HGPRTase resulting no negative feedback of the nucleotide biosynthesis and positive feedback by the abundance of PRPP
73
Orotate phosphoribosyl transferase
- enzyme that carries out Orotic acid + PRPP -> OMP
| - Hereditary Orotic Aciduria (high level of orotic acid)
74
ribonucleotide reductase
is responsible for reducing sugar (deoxy) to make DNA substrate sugars
75
6-mercaptopurine
(Purine looking) salvaged by HGPRTase and inhibits amino transferase in biosynthesis pathway
76
5-flurouracil
(pyrimidine looking)
77
Palmitic Acid
16:0
78
arachidonic acid
20:4
79
cholesterol is a precursor for?
Bile salts, vitamin D, and steroid hormones
80
cause gallstones?
Too much cholesterol in diet
Too much de novo cholesterol synthesis
Too much cholesterol secretion (with fibrates)
Deficiency in bile salt synthesis
81
Nonalcoholic "fatty liver" (hepatic steatosis)
- occurs in conditions in which there is an imbalance between hepatic TAG synthesis and the secretion of VLDL (e.g. obesity, T2D)
- high lipid concentration in liver
82
LCAT
esterfies cholesterol to keep a cholesterol gradient in HDL
83
17 alpha hydroxylase
modification of cholesterol to steroid hormones
84
CETP
exchanges cholesteryl esters for TAGs from HDL to VLDL
85
UCP-1
thermogenin) is associated with heat production in brown adipose tissue. The major function of brown adipose tissue is nonshivering thermogenesis, whereas the major function of white adipose tissue is the storage of triacylglycerols in lipid droplets.
86
DNP
unnatural coupler that defuses freely through cell membrane and carries H+ from high to low concentration (breaking H+ gradient in mitochondria)
87
B12
- Transfers a methyl group to homocysteine forming Methionine
- methylmalonyl CoA to form succinyl CoA
88
Acetyl CoA carboxylase
- enzyme that changes Acetyl CoA into Malonyl CoA in fatty acid synthesis (rate determining step)
- Biotin (B7) is a cofactor
89
Fatty acid synthase
- enzyme used in fatty acid synthesis that catalyzes the addition of two carbons
- alot of NADH use because anabolism (from pentose phosphate pathway)
90
FA synthesis occurs in the
cytosol
91
throboxane
- promotes adherence/aggregation of circulation platelets and contraction of vascular smooth muscles ->clots
- COX1
92
prostacyclin
- inhibits platelet aggregation and stimulates vasodilation
| - COX2
93
Integral Membran Protein I
single membrane helix (NH3 outside, COO- inside)
94
Integral Membran Protein II
single membrane helix (COO- outside, NH3 inside)
95
Integral Membran Protein III
single protein with multiple transmembrane helixes
96
Integral Membran Protein IV
multiple proteins that are single transmembrane helixes that interact with one another
97
Integral Membran Protein V
lipid linked protein
98
Integral Membran Protein VI
both transmembrane and lipid linked domain
99
angeograde
- Movement from – to + is called
| - uses kinesin motors
100
retrograde
- from + to – is
| - uses dynein motors.
101
Cardilipin
protein bound to head group that stabilizes ETC complexes by esterfying two head groups together
102
Platelet activating factor
protein bound to head group trigger platelet clotting and inflammatory
103
Sphingophospholipids
Backbone is the amino alcohol sphingosine, not glycerol.
104
Sphingomyelin
mylenin sheaths
105
Phosphatidyl inositol
- protein bound to phospholipid head group
- cleaved by PLC
- induces Ca2+ release
106
Nernst Potential
equilibrium potential is equal for a single ion
107
Goldman Equation
equilibrium potential is equal for multiple ions
