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Test your basic knowledge |
MCAT Organic Chemistry 2
Start Test
Study First
Subjects
:
mcat
,
science
Instructions:
Answer 50 questions in 15 minutes.
If you are not ready to take this test, you can
study here
.
Match each statement with the correct term.
Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.
This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.
1. Separation is due to charge - with negative charge moving toward positive electrode and positive charge moving toward negative electrode
addition of water across of a bond
disulfide bond
histidine - arginine - lysine
Cause of Amino acid separation in gel electrophoresis
2. Polar amino acids
histidine - arginine - lysine
serine - threonine - asparagine - glutamine - cysteine - tyrosine
antiparallel beta sheet
lactase
3. Fatty acid structure
basic amino acid has pKa at 6.5 - so it can either be protonated or deprotonated at physiological pH
long chain of unsubstituted alkanes that end in a carboxylic acid - making them amphipathic
only achiral amino acid
amphoteric
4. 2 reasons why fats have more efficient energy stores than carbs
3 things about the cyclic form of a sugar as a hemiacetal
packing and energy content
parallel beta sheet
peptide bonds and disulfide bonds
5. Acetic acid formula?
Ka
antiparallel beta sheet
CH3COOH
saturated fatty acid
6. Property of fatty acids where one end is hydrophobic and the other is hydrophilic
saturated fatty acid
furanose
amphipathic
alpha helix
7. What describes the affinity of functional groups for a proton?
Ka
glucose - alpha -1 -2- fructose
saturated fatty acid
have alkyl or aromatic side chains and tend to associate w/ each other - rather than water
8. Adjacent polypeptide strands running in the same direction in Beta pleated sheet structure
parallel beta sheet
have alkyl or aromatic side chains and tend to associate w/ each other - rather than water
1. presence of urea 2. extreme pH 3. extreme temperature 4. changes in salinity
all acidic - basic - and polar amino acids
9. (R) and (S) describe what?
absolute configuration
D- glyceraldehyde
unsaturated fatty acid
anomers
10. Adjacent polypeptide strands running in opposite directions in Beta pleated sheet structure
parallel beta sheet
unsaturated fatty acid
antiparallel beta sheet
1. form phospholipids of cellular membranes 2. store energy in adipose tissue 3. produce steroid hormones
11. 4 causes of denaturation of proteins
Proteins
1. presence of urea 2. extreme pH 3. extreme temperature 4. changes in salinity
glycine - alanine - valine - methionine - leucine - isoleucine - proline - phenylalanine - tryptophan
parallel beta sheet
12. Characteristics of acidic amino acids
optical activity
stereoisomers
D- glyceraldehyde
have acidic carboxylic acid on side chains - w/ pKa around 4
13. Acidic amino acids
secondary structure
1. form phospholipids of cellular membranes 2. store energy in adipose tissue 3. produce steroid hormones
glutamic acid and aspartic acid
7.4
14. Fxn of cholesterol in the membrane?
L- configuration
modulates fluidity and seeks to maintain optimal fluidity
glucose - beta -1 -4- glucose
NH2CONH2
15. PH at which positive and negative charges balance to form a zwitterion
only achiral amino acid
alpha helix
pI
peptide bonds and disulfide bonds
16. Interaction btw polypeptide subunits arranged in polypeptide. can be covalent bonds or intermolecular forces - disulfide bond that does not form btw residues on the same protein affect (blank)
peptide bond
quaternary structure
absolute configuration
only amino acid that his a secondary amine
17. Characteristics of polar amino acids
glutamic acid and aspartic acid
have an R group that is polar enough to H bond - but does no acts an acid or a base
lipases
only achiral amino acid
18. Molecules with the same atoms - but different bonds
quaternary structure
have alkyl or aromatic side chains and tend to associate w/ each other - rather than water
isoelectric point
isomers
19. Molecules with the same atoms and same bonds - but different bond geometries; can either be enantiomers or diastereomers
stereoisomers
galactose - beta -1 -4- glucose
secondary structure
have acidic carboxylic acid on side chains - w/ pKa around 4
20. The amino acid sequence of a protein that is determined by peptide bond
parallel beta sheet
primary structure
aldose
glucose - beta -1 -4- glucose
21. 1. it exists in solution in equilibrium with linear form 2. mutarotation occurs readily 3. it is a reducing sugar - and reacts positively w/ Benedict's reagent
furanose
serine - threonine - asparagine - glutamine - cysteine - tyrosine
starch
3 things about the cyclic form of a sugar as a hemiacetal
22. 3 carbon triol that forms backbone of triacylglycerol
glycerol
1. presence of urea 2. extreme pH 3. extreme temperature 4. changes in salinity
have acidic carboxylic acid on side chains - w/ pKa around 4
have amino group in their side chains
23. 2 things that accelerate the rate of hydrolysis for peptide cleavage?
lipases
1. presence of strong acids 2. proteolytic enzymes
mutarotation
furanose
24. Enzyme that hydrolyzes lactose into galactose and glucose into
Ka
antiparallel beta sheet
lactase
has thiol group that allows it the form disulfide bond
25. Amino group placed on the left of a fischer projection is a?
L- amino acid
phospholipids
have alkyl or aromatic side chains and tend to associate w/ each other - rather than water
has thiol group that allows it the form disulfide bond
26. Basic amino acids
lactase
histidine - arginine - lysine
have acidic carboxylic acid on side chains - w/ pKa around 4
peptide bond
27. Name for 5 membered ring
tertiary structure
unsaturated fatty acid
epimers
furanose
28. Hydrophobic and hydrophilic interactions btw amino acids more distant from each other on the polypeptide chain
ketose
tertiary structure
antiparallel beta sheet
anomers
29. What kind of lipids compromise the lipid bilayer?
glucose - beta -1 -4- glucose
only amino acid that his a secondary amine
phospholipids
aldose
30. (+) and (-) describe what?
alpha helix
anomeric carbon
amphipathic
optical activity
31. 1. it requires an enzyme to linearize and mutarotate 2. it is not a reducing sugar and give negative Benedict's test
ketose
2 things about the cyclic form of a sugar as an acetal
isomers
1. presence of urea 2. extreme pH 3. extreme temperature 4. changes in salinity
32. Initial folding of proteins into shapes stabilized by H bonds btw amino and carboxyl groups of backbone
the basic precursor of the molecule (L or D glyceraldehyde)
secondary structure
modulates fluidity and seeks to maintain optimal fluidity
Cause of Amino acid separation in gel electrophoresis
33. Rule for all amino acids that are nonbasic and nonacidic pertaining to pI value?
will have pI of 6
packing and energy content
van der Waal forces of hydrophobic tails
Cause of Amino acid separation in gel electrophoresis
34. Energy storage molecule of carbohydrates for plants
starch
pyranose
addition of water across of a bond
C3H6O3 - with one chiral center
35. Unique feature of glycine
saturated fatty acid
primary structure
unsaturated fatty acid
only achiral amino acid
36. Sugar with an aldehyde at the first carbon position
anomeric carbon
addition of water across of a bond
aldose
has thiol group that allows it the form disulfide bond
37. Covalent bond formed btw carboxyl group of one atom and the amino group of another amino acid in an addition - elimination mechanism - enzymes are required to carry out rxn
D- glyceraldehyde
basic amino acid has pKa at 6.5 - so it can either be protonated or deprotonated at physiological pH
peptide bond
have amino group in their side chains
38. What stabilizes lipid bilayer?
ketose
disulfide bond
van der Waal forces of hydrophobic tails
amphipathic
39. 1.has partial double bond character due to resonance 2. it cannot rotate 3. amide H is someWhat acidic and can H bond
Characteristics of the peptide bond
unsaturated fatty acid
CH3COOH
phospholipids
40. Diastereomers that vary in the configuration of 1 chiral center
peptide bonds and disulfide bonds
epimers
all acidic - basic - and polar amino acids
Proteins
41. Glycosidic linkage of cellulose
NH2CONH2
stereoisomers
lactase
glucose - beta -1 -4- glucose
42. Unique feature of cysteine
phospholipids
has thiol group that allows it the form disulfide bond
pI
Cause of Amino acid separation in gel electrophoresis
43. Glyceraldehyde
will have pI of 6
mutarotation
maltase
C3H6O3 - with one chiral center
44. Glycosidic linkage of lactose
Cause of Amino acid separation in gel electrophoresis
mutarotation
galactose - beta -1 -4- glucose
have acidic carboxylic acid on side chains - w/ pKa around 4
45. Macromolecule that performs a variety of bodily functions and is composed of up to 20 different amino acids
Beta pleated sheet
ketose
quaternary structure
Proteins
46. PH at which the amino acid has a net neutral charge
isomers
alpha helix
isoelectric point
pI
47. Generated btw either thiols on different proteins or thiols on the same protein
addition of water across of a bond
van der Waal forces of hydrophobic tails
mutarotation
disulfide bond
48. Fatty acid w/ one or more double bonds in cis form predominately
1. form phospholipids of cellular membranes 2. store energy in adipose tissue 3. produce steroid hormones
unsaturated fatty acid
basic amino acid has pKa at 6.5 - so it can either be protonated or deprotonated at physiological pH
Proteins
49. Epimers of sugars that vary in the configuration of their anomeric carbons
anomers
maltase
Beta pleated sheet
glucose - alpha -1 -4- glucose
50. Name for 6 membered ring
alpha helix
pyranose
L- amino acid
lactase