quiz #2 Flashcards
1
Q
Four Bases of DNA
A
Adenine Cytosine Guanine Thymine
2
Q
Purines
A
-have a pyrimidine + imidazole group combined
-structure: 3 & 5 C chain
3
Q
Purines (example)
A
Purine,Adenine,Guanine
4
Q
Pyrimidine
A
have 4C and 2C in aromatic ring
5
Q
Pyrimidine (example)
A
Pyrimidine,Cytosine,Thymine
6
Q
Base+Sugar
A
Nucleoside
7
Q
Purine Nucleosides
A
end in “sine” (ex.adenosine,guanosine)
8
Q
Pyrimidine Nucleosides
A
end in “dine” (ex.cytidine,thymidine)
9
Q
In DNA Nucleosides are attached by a…
A
Phosphodiester Backbone
10
Q
Nucleosides with phosphate groups are called
A
Nucleotides
11
Q
Nucleotides are like the “….” of DNA.
A
amino acids
12
Q
Watson Crick Base Pairing
A
1) hydrogen bonds
2) purine/pyrimidine
3)GC has 3 H-bonds
4)AT has 2 H-bonds
13
Q
deoxy-
A
nucleotides found in DNA
14
Q
DNA is
A
Antiparallel, right handed double helix, major and minor grooves
15
Q
ribose (sugar)
A
OH on 2’
16
Q
Base pairing for RNA
A
GC base pair
AU base pair
17
Q
messenger RNA (mRNA)
A
codes for 1 sequence of proteins
18
Q
transfer RNA ( tRNA)
A
binds amino acids & mRNA
19
Q
ribosomal RNA (rRNA)
A
part of ribosome, which assembles polypeptides
20
Q
Messenger RNA (mRNA) is almost identical to
A
the coding strand DNA
21
Q
gene
A
coding DNA contains a functional unit of heredity that “codes” for the 1 sequence of a protein or RNA
22
Q
Coding region codes for
A
each amino acid
23
Q
histones organize what?
A
organize DNA
24
Q
exon
A
coding DNA
25
introns
noncoding DNA
26
Open Reading Frame(ORF)
exons together
27
Protein Synthesis Starts with
Transcription
28
pre-mRNA
exons+introns
29
mature transcript
5' cap + exons+ poly-A tail
30
untranslated region
cap and poly-A tail in 5' and 3' UTR
31
mRNA coding regions are EXACTLY the same as
DNA exons
32
Transcription and Splicing Occur in
the nucleus
33
codon
3 Nucleotides
34
Each codon(4^3 = 64) codes for an
amino acid or STOP codon
35
START codon is
M ( which is the initiator codon)
36
Anticodon is the
"opposite" sequence of mRNA
37
Always write Nucleic Acids from
5' to 3'
38
Wobble Effect
explains at a biochemical level why the genetic code is degenerate
39
Translation occurs in the
cytoplasm
40
Protein Synthesis
Translation
41
Fat
Fatty Acids and Triglycerides
42
Lipids are
FA and trglycerides, phospholipids, bile/cholesterol
43
Saturated FA
no double bonds
44
Unsaturated FA
consecutive double bonds (usually cis)
45
that last carbon in a FA chain is called
the omega carbon (w)
46
FA names start with the
carboxylic acid group
47
Palmitate
C16:0
largest FA made by FASN
48
Arachidonate
C20:4
49
laureate
saturated FA
50
Palmitoleate
unsaturated FA
51
SDS is
-Sodium lauryl sulfate (SDS)
-saturated
52
Olen or Olestra
fat substitute to mimic oleate= ionized form/conjugate base of oleic acid
-unsaturated
53
cis double bond makes
a kink
54
FASN
Mammalian Fatty Acid Synthase
55
FASN is a
-quaternary protein + homodimer
-Sole enzyme responsible for de novo synthesis of long chain fatty acid
56
Acyl CoA has a
thioester bond attached to an acyl
57
A type of Acyl CoA is
Acetyl CoA
58
Acetyl CoA has a
thioester bond attached to an acetyl group
59
Acetyl CoA is a an activated coenzyme required for
fatty acid synthesis
60
Acetyl CoA is derived from
vitamin B5, glycolysis, FA and aa degradation
61
Acetyl CoA initiates
citric acid cyle
62
Acetyl CoA is more or less stable than an ester bond?
less
63
NADPH is required as an
electron donor for reduction reactions
64
Carbon Accounting
keeping track of how many carbons are present in each of the metabolites
65
synthesis of palmitate is made by a
anabolic process ( like protein synthesis)
66
FA synthesis Step 1
acetyl coA (2C) is oxidized to malonyl CoA (3C) by acetyl CoA carboxylase
-high regulated
67
ACC
Acetyl CoA Carboxylase
68
ACC1 inhinited by phosphorylation by
AMP dependent protein kinase
69
Pallmititoyl CoA(final product) inhibits
feedback inhibition ( recurring theme in enzymology & therefore metabolism)
70
FA Synthesis Step 2
-building the ACC
-Acetyl CoA (2C) and Malonyl CaA (3C) are loaded into a large ensyme complex called FASN
-joined together to make a 4C chain via ketoacyl synthase KS (CO2 is lost during condensation)
- process is repeated w, new malonyl joined to the C4 butyryl
71
How many enzymatic reactions does FA synthesis have in one round?
7
72
How many carbons does the product have in the FA biosynthesis?
4
73
KS
ketoacyl sythase
74
Mat
malonyl transferase
75
KR
ketoreductase
76
DH
dehydratase
77
ER
enoyl reductase
78
Why do we need 8 Acetyl CoA instead of 7?
malonyl CoA needs to be made
79
Fatty Acids can be used to construct
phospholipids for membrane synthesis
80
Fatty Acids can be stored in the form of
triacylglycerol or triglycerides
81
Phospholipids are
Amphipathic (very hydrophobic glycerol &hydrophilic head group)
82
Triacylglcerol or Triglyceride
storage form of FA in fat cells
83
intergral protein
embeded in the membrane had to get dettached
84
peripheral protein
located on the inner part of the membrane
85
endocytosis
Receptor binding on the surface of the cell induces the membrane to invaginate
86
Do Prokaryotes have membranes?
Yes , they have an outer and inner membrane or a thick cell wall
87
Permeability barrier
keep stuff in and keep stuff out
88
Protein Solvent
membrane is able to "dissolve" proteins . "garage for hydrophobic car"
89
Asymmetry
more of compound on the outside of the cell compared to the inside (vice versa)
90
Fluidity/Signaling
diffusion, concentrate proteins and lipids in 2 dimensions
91
Unsaturated FA C18:0 + C18:1
oleate, cis
creates high fluidity (kink)
92
Higher Tm =
high chain length and high saturation
93
cholesterol
membrane fluidity
94
LDL
transport mechanism of cholesterol
95
Cholesterol concentration impacts
stacking and membrane fluidity
96
Key Cholesterol Functions (4)
1.Membrane Fluidity
2.Precursors of vitamin D(COVID-19)
3.Precursor of bile salts for digestion
4.Precursors of steroid hormones such as testosterone and estradiol
97
Excess Cholesterol is linked to
Cardiovascular diseases such as atherosclerosis
98
What was the leading cause of death in the US compared to all cancers combined?
heart disease not including stroke
99
Anti-platelet drugs (ex.aspirin, clopidogrel)
the standard care for patients at high risk for thrombosis
100
What drugs competitively inhibit HMG CoA Reductase?
Statins (Lovastatin)
101
HMG CoA + 2 NADPH + 2H+
Mevalonate + NADP+ + CoA
102
Cushing syndrome
excess cortisol
