SUBJECTS
|
BROWSE
|
CAREER CENTER
|
POPULAR
|
JOIN
|
LOGIN
Business Skills
|
Soft Skills
|
Basic Literacy
|
Certifications
About
|
Help
|
Privacy
|
Terms
|
Email
Search
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. Hydrophilic amino acids
2 things about the cyclic form of a sugar as an acetal
all acidic - basic - and polar amino acids
ketose
cysteine and methionine
2. 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
furanose
parallel beta sheet
peptide bond
antiparallel beta sheet
3. Generated btw either thiols on different proteins or thiols on the same protein
have an R group that is polar enough to H bond - but does no acts an acid or a base
disulfide bond
ketose
1. presence of urea 2. extreme pH 3. extreme temperature 4. changes in salinity
4. Unique feature of proline
only amino acid that his a secondary amine
quaternary structure
anomeric carbon
have an R group that is polar enough to H bond - but does no acts an acid or a base
5. Name for 5 membered ring
glycogen
furanose
van der Waal forces of hydrophobic tails
Characteristics of the peptide bond
6. What configuration do all naturally occuring amino acids have?
L- configuration
only amino acid that his a secondary amine
the basic precursor of the molecule (L or D glyceraldehyde)
basic amino acid has pKa at 6.5 - so it can either be protonated or deprotonated at physiological pH
7. Interconversion btw two anomers
NH2CONH2
mutarotation
long chain of unsubstituted alkanes that end in a carboxylic acid - making them amphipathic
modulates fluidity and seeks to maintain optimal fluidity
8. 3 carbon triol that forms backbone of triacylglycerol
glycerol
glycine - alanine - valine - methionine - leucine - isoleucine - proline - phenylalanine - tryptophan
triacylglycerol
isoelectric point
9. Molecules with the same atoms and same bonds - but different bond geometries; can either be enantiomers or diastereomers
peptide bonds and disulfide bonds
CH3COOH
anomers
stereoisomers
10. Property of fatty acids where one end is hydrophobic and the other is hydrophilic
amphipathic
glucose - beta -1 -4- glucose
L- configuration
1. presence of urea 2. extreme pH 3. extreme temperature 4. changes in salinity
11. 4 causes of denaturation of proteins
stereoisomers
CH3COOH
will have pI of 6
1. presence of urea 2. extreme pH 3. extreme temperature 4. changes in salinity
12. Initial folding of proteins into shapes stabilized by H bonds btw amino and carboxyl groups of backbone
secondary structure
lactase
anomeric carbon
maltase
13. Diastereomers that vary in the configuration of 1 chiral center
all acidic - basic - and polar amino acids
epimers
aldose
L- amino acid
14. 2 covalent bonds formed in proteins
basic amino acid has pKa at 6.5 - so it can either be protonated or deprotonated at physiological pH
optical activity
7.4
peptide bonds and disulfide bonds
15. What describes the affinity of functional groups for a proton?
furanose
Ka
NH2CONH2
C3H6O3 - with one chiral center
16. Glycosidic linkage of sucrose
amphipathic
have an R group that is polar enough to H bond - but does no acts an acid or a base
the basic precursor of the molecule (L or D glyceraldehyde)
glucose - alpha -1 -2- fructose
17. Adjacent polypeptide strands running in the same direction in Beta pleated sheet structure
glutamic acid and aspartic acid
parallel beta sheet
absolute configuration
anomeric carbon
18. Separation is due to charge - with negative charge moving toward positive electrode and positive charge moving toward negative electrode
1. presence of urea 2. extreme pH 3. extreme temperature 4. changes in salinity
Ka
anomers
Cause of Amino acid separation in gel electrophoresis
19. Name for 6 membered ring
epimers
phospholipids
L- amino acid
pyranose
20. Characteristics of acidic amino acids
1. presence of strong acids 2. proteolytic enzymes
have acidic carboxylic acid on side chains - w/ pKa around 4
addition of water across of a bond
pyranose
21. Physiological pH
7.4
pI
primary structure
furanose
22. Acetic acid formula?
quaternary structure
pyranose
CH3COOH
glucose - beta -1 -4- glucose
23. Acidic amino acids
NH2CONH2
van der Waal forces of hydrophobic tails
pI
glutamic acid and aspartic acid
24. Naturally occurring carbohydrates are formed from what?
D- glyceraldehyde
long chain of unsubstituted alkanes that end in a carboxylic acid - making them amphipathic
1. form phospholipids of cellular membranes 2. store energy in adipose tissue 3. produce steroid hormones
disulfide bond
25. Characteristics of hydrophobic amino acids
antiparallel beta sheet
amphoteric
modulates fluidity and seeks to maintain optimal fluidity
have alkyl or aromatic side chains and tend to associate w/ each other - rather than water
26. Enzyme that hydrolyzes lactose into galactose and glucose into
epimers
L- amino acid
triacylglycerol
lactase
27. Unique feature of glycine
only achiral amino acid
quaternary structure
van der Waal forces of hydrophobic tails
L- amino acid
28. Basic amino acids
histidine - arginine - lysine
cysteine and methionine
1. form phospholipids of cellular membranes 2. store energy in adipose tissue 3. produce steroid hormones
7.4
29. Epimers of sugars that vary in the configuration of their anomeric carbons
the basic precursor of the molecule (L or D glyceraldehyde)
anomers
triacylglycerol
disulfide bond
30. Unique feature of cysteine
has thiol group that allows it the form disulfide bond
cysteine and methionine
quaternary structure
D- amino acid
31. Structure where H bonds occur btw residues distant from each other - or on a separate chain. backbone is extended rather than coiled
van der Waal forces of hydrophobic tails
Beta pleated sheet
Characteristics of the peptide bond
quaternary structure
32. Polar amino acids
C3H6O3 - with one chiral center
lactase
glycogen
serine - threonine - asparagine - glutamine - cysteine - tyrosine
33. Formula for urea
addition of water across of a bond
glucose - alpha -1 -4- glucose
disulfide bond
NH2CONH2
34. 2 reasons why fats have more efficient energy stores than carbs
have alkyl or aromatic side chains and tend to associate w/ each other - rather than water
optical activity
packing and energy content
isoelectric point
35. Sugar with an aldehyde at the first carbon position
aldose
glucose - alpha -1 -4- glucose
serine - threonine - asparagine - glutamine - cysteine - tyrosine
epimers
36. (R) and (S) describe what?
absolute configuration
maltase
CH3COOH
pyranose
37. Amino group placed on the left of a fischer projection is a?
packing and energy content
peptide bonds and disulfide bonds
L- amino acid
the basic precursor of the molecule (L or D glyceraldehyde)
38. Molecule can act as a base and as an acid
isomers
amphoteric
modulates fluidity and seeks to maintain optimal fluidity
primary structure
39. What stabilizes lipid bilayer?
isomers
stereoisomers
Characteristics of the peptide bond
van der Waal forces of hydrophobic tails
40. Rule for all amino acids that are nonbasic and nonacidic pertaining to pI value?
serine - threonine - asparagine - glutamine - cysteine - tyrosine
L- amino acid
will have pI of 6
epimers
41. Fatty acid structure
have an R group that is polar enough to H bond - but does no acts an acid or a base
long chain of unsubstituted alkanes that end in a carboxylic acid - making them amphipathic
triacylglycerol
glycerol
42. Right handed helix w/ carboxyl of one amino acid bound to the amine of another amino acid three residues away - proline never resides in this structure b/c it would place a kink in the helix
glutamic acid and aspartic acid
alpha helix
2 things about the cyclic form of a sugar as an acetal
optical activity
43. What kind of lipids compromise the lipid bilayer?
have acidic carboxylic acid on side chains - w/ pKa around 4
phospholipids
the basic precursor of the molecule (L or D glyceraldehyde)
L- amino acid
44. Glycosidic linkage of cellulose
have acidic carboxylic acid on side chains - w/ pKa around 4
glucose - beta -1 -4- glucose
amphipathic
disulfide bond
45. Fatty acid w/ one or more double bonds in cis form predominately
glucose - alpha -1 -2- fructose
unsaturated fatty acid
aldose
have amino group in their side chains
46. Histidine
basic amino acid has pKa at 6.5 - so it can either be protonated or deprotonated at physiological pH
Characteristics of the peptide bond
CH3COOH
have acidic carboxylic acid on side chains - w/ pKa around 4
47. Glycosidic linkage of lactose
galactose - beta -1 -4- glucose
alpha helix
the basic precursor of the molecule (L or D glyceraldehyde)
glucose - beta -1 -4- glucose
48. Fatty acid w/ no double bonds and maximum number of hydrogens
glycine - alanine - valine - methionine - leucine - isoleucine - proline - phenylalanine - tryptophan
tertiary structure
saturated fatty acid
7.4
49. The amino acid sequence of a protein that is determined by peptide bond
L- amino acid
D- glyceraldehyde
Beta pleated sheet
primary structure
50. 3 physiological roles of lipids
1. form phospholipids of cellular membranes 2. store energy in adipose tissue 3. produce steroid hormones
glycogen
peptide bond
isoelectric point