Chap 3: An Intro to Protein Structure and Function

Question 1

Amino acids are the

Answer 1

building blocks of proteins

Question 2

Amino acids contain

Answer 2

Amine and carboxylic acid function groups

Question 3

Zwitterion

Answer 3

A molecule that possesses both a positive and negative charge

Ex. an amino acid at neutral pH

Question 4

Animo Acid Classification: Nonpolar (hydrophobic)

Answer 4

Usually an alkyl group , an aromatic ring, or hydrogen

C-H bonds (Lipids)

Question 5

Animo Acid Classification: Polar

Answer 5

Side chain is polar or ionic
O-H bonds

Question 6

Amino acids roles in biochemistry

Answer 6

• Lipid metabolism
• Amino acid metabolism
• Neurotransmission

Question 7

Peptide Bond (definition)

Answer 7

the linkage between two amino acids

Question 8

Peptide bond

Answer 8

An amide linkage between the carboxyl group of amino acid and the amino group

(water molecule is removed in order for an amide bond to form)

Question 9

Types of peptides bonds

Answer 9

Dipeptides (2 amino acids)
Oligopeptides (4-20 amino acids)
Polypeptides (20 or more)

Question 10

Monomers

Answer 10

Single chains of amino acids folded into an active protein

Question 11

Multimers

Answer 11

Consists of several subunits;
Subunits labeled based on function (i.e. catalytic and regulatory)

Question 12

Cofactors

Answer 12

nonprotein groups required for protein binding or activity

*can be divided into two categories minerals and vitamins

Question 13

Kinases

Answer 13

enzymes that catalyze phosphorylation reactions

• ATP typically source of phosphate

Question 14

Four levels of protein structure

Answer 14

Primary
Secondary
Tertiary
Quaternary

Question 15

Primary Structure

Answer 15

Linear arrangement
amino is the beginning and carboxyl is last
Held together by peptide bonds

Question 16

Secondary Structure

Answer 16

Held together by hydrogen bonds
Two major structural elements:
1) alpha helix
2) beta sheet

Question 17

Types of Beta sheets

Answer 17

Parallel and Antiparallel
Hydrogen (amino) to oxygen (carboxyl) bond
Antiparallel straight bond stronger

Question 18

Tertiary Structure

Answer 18

Combination of Alpha Helix and Beta Sheets

Question 19

Motifs

Answer 19

Combination of secondary structures

Question 20

Domains

Answer 20

Pieces of a protein that retain their structure in the absence of the rest of the protein

Question 21

Bonds Forces involved in Tertiary Structure

Answer 21

Hydrogen Bonding
London Dispersion Forces
Dipole-Dipole Interactions
Salt Bridges
etc.

Question 22

Hydrophobic Effect

Answer 22

Describes the phenomenon in which hydrophobic groups cluster (fold) together

Question 23

Quaternary Structure

Answer 23

Complex structure that incorporates multiple subunits or different proteins

Question 24

Collagen is a

Answer 24

structural protein
(found in tissue and bones)

Question 25

Hemoglobin is a

Answer 25

transport protein
(found in red blood cells)

Question 26

Immunoglobulins are

Answer 26

binding proteins

Question 27

Insulin is a

Answer 27

Signaling protein
(Produced by pancreatic cells)