Chapter (1) lecture 2 - Proteins Part (1)

Question 1

What is the main idea of CYStine?

Answer 1

Cysteine—the most reactive amino acid—can form disulfide-bonded cysteine.

Question 2

What is the most reactive amino acid?

Answer 2

Cysteine

Question 3

Why is cysteine so important?

Answer 3

It can form disulfate-bonded cysteine.

Question 4

Amino acids can be held together by _ amide bonds called _.

Answer 4

Amino acids can be held together by amide bonds called peptide bonds.

Question 5

Biological polypeptides are divided into_ and , depending on their.

Answer 5

Biological polypeptides are divided into peptides and proteins, depending on their length.

Question 6

Protein _ structure is the sequence of _.

Answer 6

Protein primary structure is the sequence of amino acids.

Question 7

What are the two most common types of protein secondary structures called?

Answer 7

Alpha Helix

Beata strand sheet.

Question 8

What is the dimensional arrangement of the protein that has a tertiary structure?

Answer 8

Three-dimensional arrangement of the molecule in space.

Question 9

_ interactions hold the tertiary structure together

Answer 9

Non-local interactions

Question 10

Protein quaternary structure has some proteins and involves the association of more than one _ structure into the _.

Answer 10

Protein quaternary structure—which some proteins have—involves the association of more than one tertiary
structure into the functional protein

Question 11

Large quaternary complexes can create _.

Answer 11

fibrous proteins

Question 12

What two methods destroy protein function?

Answer 12

1. Denaturation
2. Aggregation

Question 13

Name the five protein roles?

Answer 13

1. Enzymes - The proteins that catalyze specific chemical reactions in a bio-system.
2. Structure
3. Transport
4. Binding
5. Signaling - Gulcogon and Inslion

Question 14

EL Camino Rymes with _ amino

Only the _ amino acids are found in proteins

Answer 14

Only L amino acids are found in proteins.

Question 15

In a L Isomer What are the two charges that NH2 and NH3+ be?

Answer 15

They can be NH2 neutral or NH3+ Postive

Question 16

In a L isomer what is the charge on the COOH?

Answer 16

Can be COO-; negative or COOH neutral

Question 17

Ionization of Amino acids are a fuction of _.

Answer 17

pH

Question 18

When pH=Pka of an ionizable group, the group would be what percentage protoated?

Answer 18

50%

Question 19

When pH< Pka of an ionizable group, the group would be what percentage protoated?

Answer 19

The group will be more protonated.

Question 20

When pH > Pka of an ionizable group, the group would be what percentage protoated?

Answer 20

The group will be more deprotonated.

Question 21

What is a Zitterion?

Answer 21

Contains only a postive and negative ion.

Question 22

How is the isoelectic point of a moleclue found.

Answer 22

It is found where the Zwitterion that has a postive and negative ion and whatever the pH happens to be will be the isolelctic point of that molecule.

Question 23

A carboxyl group ( coo-) has a pka of ~ _.

Answer 23

2ish

Question 24

The Amino group (NH3+) has a pka of _.

Answer 24

9ish

Question 25

A Zwitterion has _ and _ charge.

Answer 25

Positive and Negative charge

Question 26

Name this special type of Amino acid at neutral pH.

Answer 26

Zwitterion

Question 27

What is this Amino Acid?

Answer 27

Lysine

Question 28

What is the Abbreviation for lysine and the letter?

Answer 28

Lys, K