Exam 1 9/6 Dr. Howard Flashcards
(105 cards)
1
Q
Globular proteins function
A
- regulatory, maintenance and catalytic roles
- dissolve or form colloidal suspensions in water
- sensitive to temperature and pH change
2
Q
What are fatty acids?
A
long chain hydrocarbons represented by the chemical formula R-COOH
3
Q
Enzyme regulation is accomplished by:
A
amount of enzyme, modification of enzyme activity
4
Q
Examples of fibrous proteins
A
collagens and elastins, keratins, fibrin
5
Q
Triglycerides are hydrolyzed by:
A
lipases
6
Q
Which amino acids are acidic?
A
glutamic acid, aspartic acid
7
Q
How to overcome competitive inhibitor
A
increase substrate concentration
8
Q
Which amino are aliphatic?
A
glycine, alanine, valine, leucine, isoleucine
9
Q
uncompetitive inhibitors
A
bind to ES complex, cannot be overcome by more S
10
Q
lineweaver burk plot x axis intercept
A
-1/kM
11
Q
True or false: sucrose is a reducing sugar
A
False - no free anomeric carbon
12
Q
Two categories of proteins
A
Fibrous proteins and globular proteins
13
Q
True or false: alpha carbon in amino acid is chiral
A
True - it is asymmetrical so is a chiral center, except for glycine
14
Q
HbA1C
A
Measure of long term glucose control
15
Q
Examples of molecules where carbohydrates are attached to noncarbohydrates
A
-purine and pyrimidine bases
-aromatic rings (ie steroids)
-proteins (glycoproteins, proteoglycans)
-lipids
16
Q
keratins are major components of
A
skin and hair
17
Q
When a hemiacetal is formed, what is created?
A
Anomeric carbon at carbon 1 (asymmetric)
18
Q
Fructose anomeric carbon
A
Carbon 2
19
Q
Catabolism
A
Releases energy to break down polymers into monomers
20
Q
Most abundant lipid
A
triglycerides
21
Q
Glycogen structure
A
Heavily branched linked chains of glucose (alpha 1,4 and 1,6 linkages)
22
Q
Characteristics of fibrous proteins (3)
A
- fiber-like structures
- insoluble in water
- unaffected by changed in temperature and pH
23
Q
Velocity ___ with substrate concentration
A
increases (eventually reaches vmax when all active sites are saturated)
24
Q
Polar amino acids
A
S T N Q D E H K R C Y
25
HbA1C measured by:
amount of glycosylated hemoglobin. Normal people <6%, diabetic >10%
26
__ is chiral for glyceraldehyde
C2
27
Hydroxyl group can react with aldehyde or ketone to form:
Hemiacetal (ring structure)
28
Proline causes:
bends in proteins
29
aldohexose has _ chiral centers
4
30
Carbonic anhydrase catalyzes:
forward and backwards reaction of bicarbonate buffer system between CO2 + H2O <-> H2CO3
31
Protein that forms when blood clots
Fibrin
32
Acylglycerols
neutral fat, glycerides
33
Enzyme kinetics Km:
substrate concentration where velocity is at half of max
34
lineweaver burk plot slope
km/vmax
35
competitive inhibitor effect on km and vmax:
increases kM, vmax stays the same
36
Which amino acids have negative charges at pH 7?
aspartic acid, glutamic acid
37
True or false: there are only trace amounts of free fatty acids in the body
True
38
AGE
advanced glycosylation end products; AGE = glucose + products
39
smallest carbohydrates are:
aldose and ketose (3 carbons)
40
Which amino acids are neutral?
serine, threonine, asparagine, glutamine
41
which residue is hydroxylated in collagen?
proline and lysine
42
Anabolism
Monomers are used to create polymers with energy input (build molecules)
43
Aromatic amino acids unique property
Absorb uv light ~280 nm
44
Sucrose
glucose + fructose
45
The arrangement of sugars into D and L configurations is based upon their resemblance to D and L?
Glyceraldehyde
46
Product of starch digestion
beta-maltose
47
Naturally occurring form of carbohydrates in humans is mostly ___
D enantiomer
48
aldohexose has _ stereoisomers
2^4 = 16 (8 D sugars, ex glucose, mannose, fructose)
49
How is enzyme activity modified
1. allosteric control (changes in substrate, activators, inhibitors)
2. isozymes of multiple forms of enzyme
3. covalent modifications
50
True or false: cellulose is digestible
False - we do not have the enzymes to break it down
51
Difference in structure of galactose and glucose
orientation of the hydroxyl group (OH) at carbon 4
52
Principle fat storage is via what molecule?
triglycerides
53
How are -uronic acids formed?
OH group replaced by an -NH2 or acetylated -NH2
54
D-glucose preferred structure
Ring. more stable
55
Which 3 reactions of the 4 basic biological compounds require condensation reactions?
protein synthesis, DNA and RNA formation from nucleotides, starch/glycogen production from monosaccharides
56
Reducing sugar assay for measuring blood sugar levels
Benedicts/Fehlings solution is heated, reduces Cu2+ to Cu+, forms red colored precipitate
57
Isoelectric point
pH at which there is equal number of positive and negative ions so overall charge is zero
58
glucose, galactose, and six other sugars are all:
aldohexoses
59
____ _____ of glutamate in prothrombin - an essential blood clotting factor; requires ______
gamma carboxylation; requires vitamin k
60
aliphatic
having a straight or branched chain structure; opposite of aromatic
61
amphoteric
able to react both as a base and as an acid
62
Most abundant sterol in animal tissue
Cholesterol
63
example of ketohexose
fructose
64
noncompetitive inhibitor effect on km and vmax:
decrease vmax, kM unchanged
65
Collagens are found in
skin, bone, tendon, cartilage, teeth
66
Which amino acids can be phosphorylated?
tyrosine, serine, threonine
67
Which amino acids contain sulfur?
cysteine, methionine
68
Amylases like ptyalin in saliva digest ____ to form ____
starch; maltose
69
cellulose is linked by:
beta 1,4 linkages
70
Which amino acids do sugar linkages occur on?
S, T, N
71
Which amino acids are basic?
histidine, lysine, arginine
72
What is the exception to protein molecules as enzymes?
ribozymes
73
Allosteric enzymes show ___ curve
sigmoidal
74
Function of bicarbonate buffer system:
1. maintain blood pH
2. Used extensively to create acidic or alkaline environments
75
True or false: there is an anomeric carbon in sucrose
False
76
Nonpolar amino acids:
G A L V I M F W P
77
____ is found at every 3rd amino acid in collagen
glycine (G)
78
What does AGE do
alters normal protein function, detrimental (aging, arteriosclerosis, diabetes)
79
Polypeptide chain backbone has large potential for:
hydrogen bonding
80
Function of lipids
1. energy storage
2. structural components of membrane
3. precursors for hormones, vitamins, bile salts
4. cellular messengers
5. lipid mediators
81
collagen is made up of
3 helical polypeptides
82
True or false: biomembranes require condensation reactions in order to form
False - spontaneously form due to nature of lipids
83
uncompetitive inhibitor effect on km and vmax:
decreases both
84
Globular proteins characteristics
nonpolar interior, polar charged on surface
85
Phosphoglycerides made from:
alcohol component esterified to phosphoric acid group to form phosphodiester
86
ketohexose # of D sugars
4
87
Which amino acids are aromatic?
tyrosine, phenylalanine, tryptophan
88
collagens and elastins are found in:
connective tissues, tendons, ligaments
89
Which isomer is found exclusively in proteins?
L isomer
90
competitive inhibitor competes for:
active site
91
Which amino acid is methylated in membrane receptors
Histidine
92
True or false: All monosaccharides are reducing sugars
True
93
Lactose bond
beta 1,4 linkage
94
True or false: noncompetitive inhibitor can be overcome by increasing S
false
95
Bicarbonate buffer system equation
CO2 + H2O <-> H2CO3 <-> H+ + HCO3-
96
True or false: maltose is a reducing sugar
True
97
noncompetitive inhibitor binds to:
site other than active site, can bind to enzyme or enzyme substrate complex
98
____ is the most abundant carbohydrate in mammalian cells
Glycogen
99
amphipathic
having both hydrophilic and hydrophobic parts
100
How many residues of glucose in cellulose?
>3000
101
Starch made up of:
more than 200 molecules of glucose
102
Which amino acids can form disulfide bridges?
cysteine
103
lineweaver burk plot y axis intercept
1/vmax
104
___ proteins are not sensitive to changes in temperature and pH
fibrous proteins
105
In tissues, glucose is converted to:
glycogen (liver and muscles)
