Brainscape's Knowledge GenomeTM

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


See full index

C30- AMINO ACIDS, PROTEINS, AND DNA > 30.2- PEPTIDES, POLYPEPTIDES, AND PROTEINS > Flashcards

30.2- PEPTIDES, POLYPEPTIDES, AND PROTEINS Flashcards

You may prefer our related Brainscape-certified flashcards:
Biology 101 flashcards
1
Q

What do amino acids link together to form?

A

peptides

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

What are molecules containing up to about 50 amino acids referred to as?

A

polypeptides

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

What is it called when there are more than 50 amino acids?

A

proteins

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

Examples of naturally occurring proteins? (4)

A

enzymes
wool
hair
muscles

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

What is the functional group of an amide?

A

-CONH2

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

What can the amine group of one amino acids react with a carboxylic acid group of another to form?

A

amide linkage -CONH-

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

What are compounds formed by the linkage of amino acids called?

A

peptides

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

What is a peptide with two amino acids called?

A

dipeptide

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

What groups does a dipeptide retain?

A

retains -NH2 and -CO2H groups and so can react further to give tri- and tetra-peptides, and so on

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

What is the primary structure of a protein?

A

fixed sequence of amino acids

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

What type of polymers are polypeptides and proteins?

A

condensation polymers

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

Why are polypeptides and proteins condensation polymers?

A

as a small molecule eliminated as each link of chain forms

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

What happens when a protein or peptide is boiled with HCl of conc. 6moldm-3 for about 24hrs?

A

breaks down to mixture of all amino acids that made up original protein or peptide

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

What happens to the peptide linkages when a protein or peptide is boiled in HCl of conc. 6moldm-3 for about 24 hrs?

A

all peptide linkages hydrolysed by acid

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

How is the complex shape of proteins held in position?

A

by hydrogen bonds + other intermolecular forces + sulfur-sulfur bonds

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

Example of how the shape of proteins are vital to their functions?

A

enzymes + structural materials in living things

17
Q

What structure do many proteins have?

A

helical

18
Q

What is the helix of proteins held by?

A

hydrogen bonding

19
Q

What is another structure of proteins other than the helix?

A

pleated sheet

20
Q

What is wool?

A

protein fibre with helix held together by hydrogen bonds

21
Q

What happens to the hydrogen bonding and fibre when wool is gently stretched?

A

hydrogen bonds stretch + fibre extends

22
Q

When releasing wool after it has been stretched, what does this allow?

A

allows hydrogen bonds to return to their normal length + fibre returns to its original shape

23
Q

What can washing wool at high temps do?

A

permanently break hydrogen bonds + garment may permanently lose its shape

24
Q

How can the amino acids in a protein chain bond together (3)

A

hydrogen bonding
ionic attractions
sulfur-sulfur bonds

25
Q

What three levels of structure do all proteins have?

A

primary, secondary and tertiary

26
Q

What is the primary structure of a protein held by?

A

covalent bonding

27
Q

As the primary structure of a protein is held by covalent bonding, what is its stability like?

A

relatively stable

28
Q

What is the secondary structure of a protein?

A

protein may form helix or folded sheet

29
Q

What is the secondary structure held in place by?

A

hydrogen bonding

30
Q

What is the strength of hydrogen bonding like on comparison to covalent bonds?

A

hydrogen bonds much weaker than covalent bonds

31
Q

How can the secondary structure of proteins be disrupted?

A

by gentle heating or changes in pH

32
Q

What is the tertiary structure?

A

α-helix or β-pleated sheet being folded into a three dimensional shape

33
Q

What is the tertiary structure held in place by?

A

mixture of hydrogen bonding, ionic interactions and sulfur-sulfur bonds

34
Q

What shapes do most proteins fold into?

A

globular shapes

35
Q

Example of techniques used to determine the secondary and tertiary structures of proteins and what it can do?

A

X-ray diffraction- can locate actual positions of atoms in space

36
Q

What is the first step in determining the primary structure?

A

find out number of each type of amino acid present in protein

37
Q

How is the process if determining the primary structure of protein done?

A

protein refluxed with 6moldm-3 HCl
process called hydrolysis
breaks amide bonds between amino acids and results in mixture containing all individual amino acids in original protein

C30- AMINO ACIDS, PROTEINS, AND DNA (5 decks)

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