Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Biochemistry > Amino Acid and Proteins > Flashcards

Amino Acid and Proteins Flashcards

1
Q

what is the structure of an amino acid?

A

central alpha carbon with amino acid, carboxyl, R group and hydrogen atom attached

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what is a zwitterion?

A

single species with both positive and negatively charged parts yet no overall charge

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

how does a zwitterion have no overall charge?

A

at pH 7, amino group is positively charged and carboxyl group becomes negatively charged

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

are polar chains hydrophilic or hydrophobic?

A

hydrophilic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

how are amino acids classified?

A

non-polar or polar and positively or negatively charged

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what is the simplest amino acid?

A

glycine, followed by alanine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what amino acids have an aliphatic side chain?

A

valine, leucine, isoleuine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what does an aliphatic side chain do?

A

causes non-polarity and hydrophobicity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what is a feature of proline?

A

ring structure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what is a feature of phenylalanine?

A

has aromatic rings in the side chain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what makes serine/threonine/tyrosine hydrophilic?

A

-OH group

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what is a feature of cysteine?

A

has -SH rather then OH which forms disulphide groups

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what are the positively charged amino acids?

A

lysine, histidine and arginine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what are the negatively charged amino acids?

A

aspartic acid and glutamic acid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what makes aspartic acid and glutamic acid negatively charged?

A

acidic and ionisable side chains

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what does having ionisable side chains allow the amino acid to do?

A

Donate or accept electrons to facilitate reactions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what is a stereoisomer?

A

same molecular formula and connectivity but different arrangement of atoms in space

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what is an enantiomer?

A

non-super imposable mirror images of the same molecule

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what is racemization?

A

process where a compound converts from one enantiomer in a pure form to an equal distribution of both

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

where does a peptide bond form between two amino acids?

A

carboxyl group of one and amino group of another

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

In what way are amino acids always written?

A

N terminus to C terminus

22
Q

how are peptide bonds planar?

A

the 6 atoms surrounding the bond are on the same plane

23
Q

what enables the peptide bond to have movement?

A

delocalised electrons fluctuate around the single and double bond

24
Q

are peptide bonds charged or uncharged?

A

uncharged

25
Q

most peptide bonds are trans, what effect does this have?

A

this is when the oxygen and hydrogen are across from each other, which influences the confirmation and structure of the protein

26
Q

how many amino acids are there per turn of the alpha helix?

A

3.6

27
Q

how might steric clashes occur in an alpha helix?

A

the rings do not sit well on top of each other and may push each other away

28
Q

what effect is caused when an amino acid has a lot of alpha helices`?

A

amino acids with large amounts of helices are typically soluble

29
Q

how do left and right handed helices differ?

A

hydrophobic right and hydrophilic left

30
Q

which version of beta pleated sheet is more stable?

A

parallel is more stable

31
Q

what is a motif?

A

combination of helices and beta sheets and loops

32
Q

how is the tertiary structure stabilised?

A

by non-covalent interactions between side chains

33
Q

what kind of covalent bonding is present at tertiary structure?

A

disulphide bridges

34
Q

what is a domain?

A

several motifs packed together

35
Q

are domains independent from each other?

A

yes yet linked at the primary level

36
Q

how can proteins be linked together in the same family?

A

when they have similar sequences and domains

37
Q

what is quaternary structure?

A

multiple subunits which have an independent polypeptide chain

38
Q

what is an oligomer?

A

a protein with multiple subunits

39
Q

how is quaternary structure stabilised?

A

by weak non-covalent bonding and hydrophobic interactions with electrostatic forces contributing

40
Q

what are the protein-protein interactions?

A

H bonding, charge-charge interactions, van der Walls forces and hydrophobic interactions

41
Q

where are salt bridges present?

A

deep inside the hydrophobic part of the protein

42
Q

in what ways are bond interactions disrupted to denature a protein?

A

chemically, temperature and pressure

43
Q

what requires more energy, denaturation or renaturation?

A

renaturation

44
Q

how do proteins move up and down the energy well?

A

they fall down the energy well when they become folded

45
Q

what pathway will the protein always take?

A

the pathway requiring less energy

46
Q

what does hydroxylation do?

A

adds an OH

47
Q

when does hydroxylation occur? where is it found?

A

immediately after amino acid chain completed and in collagen

48
Q

what does hydroxylation require?

A

vitamin C

49
Q

what does glycosylation do?

A

adds sugar chains

50
Q

where is glycosylation found and what does it do?

A

in secreted proteins and proteins on the surface of cells, stabilises protein structure

51
Q

what are the features of phosphorylation?

A

reversible, can occur multiple times throughout the life of the protein and important in control of enzyme activity

Biochemistry (9 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions