Lecture 1: Protection Structure and Function, Part 1

Question 1

What are building blocks?

Answer 1

Subunits that are used to form macromolecules

Question 2

What are macromolecules?

Answer 2

Large organic molecules

Question 3

How are macromolecules formed?

Answer 3

Macromolecules are formed by generating strong covalent bonds between small organic molecules powered by hydrolysis and condensation reactions

Question 4

What are the 4 building blocks of cells?

Answer 4

Sugars, Amino Acid, Nucleotide, and Fatty Acids

Question 5

What macromolecule do sugars make and how are they linked?

Answer 5

Sugar makes polysaccharide (includes glycogen and starch
Linked by glyosidic bonds

Question 6

What macromolecule do amino acids make and how are they linked?

Answer 6

Amino acids make proteins
Linked by peptide bonds

Question 7

What macromolecule do nucleotides make and how are they linked?

Answer 7

Nucleotides make nucleic acids
Linked by phosphodiester bonds

Question 8

What macromolecule do fatty acids make and how are they linked?

Answer 8

Fatty acids make up fats and membrane lipids
Linked by ester bonds

Question 9

What are condensation reactions?

Answer 9

Two molecules combine to form single molecule often by removal of water
Energetically unfavorable and not spontaneous

Question 10

What are hydrolysis reactions?

Answer 10

Molecules broken by adding water
Energetically favorable and spontaneous

Question 11

Why do cells couple hydrolysis condensation reactions?

Answer 11

By coupling both condensation (energetically unfavorable) and hydrolysis reactions (energetically favorable) is able to power the reaction

Question 12

What is the general structure of amino acid?

Answer 12

Alpha carbon attached to amino group, carboxyl group, and unique side chain

Question 13

How is the structure of an amino acid in water (pH 7)?

Answer 13

In water, free amino acids exist in ionized from
Amino group accepts a proton and carboxyl group donates a proton
Overall charge is neutral

Question 14

How do amino acids differ?

Answer 14

Amino acids differ through 20 different side chains

Question 15

What is N-terminus?

Answer 15

First amino acid in polypeptide backbone

Question 16

What is C-terminus?

Answer 16

Last amino acid in polypeptide backbone

Question 17

What is side chain/ R group?

Answer 17

a chemical group attached to the alpha carbon which distinguishes one amino acid from another, accounts for different chemical properties that are critical for protein structure and function

Question 18

What are polar amino acids?

Answer 18

Hydrophilic amino acids that form hydrogen bonds and prefer to interact with water

Question 19

What amino acids are polar?

Answer 19

Uncharged: STQNY
Negative: DE
Positive: KRH

Question 20

What are nonpolar amino acids?

Answer 20

Hydrophobic amino acids that cannot form hydrogen bonds and repel water

Question 21

What amino acids are nonpolar?

Answer 21

GAVC LIMP

Question 22

What amino acids can from hydrogen bonds?

Answer 22

Polar amino acids which have free hydroxyl group
STQNY, DE, KRH

Question 23

Which amino acids can from electrostatic repulsions?

Answer 23

Charged amino acids
DE and KRH

Question 24

What amino acids can from hydrophobic forces?

Answer 24

Nonpolar amino acids
GAVC LIMP

Question 25

What is role of covalent bonds in protein structure?

Answer 25

Covalent peptide bonds link amino acids in polypeptide chain
Nonpolar amino acids cluster in core

Question 26

What is role of noncovalent bonds in protein structure?

Answer 26

Include hydrogen bonds, electrostatic interactions, van der waals attractions
Exist between polar amino acids influence 3-D shape of protens

Question 27

What is role of hydrophobic interactions in protein structure?

Answer 27

Plays critical role in determining shape of protein as nonpolar amino acids cluster in core

Question 28

What is the tertiary structure of proteins?

Answer 28

collection of secondary structures in protein and is 3-D arrangement of all atoms in a protein of single polypeptide chain and involves interactions between side chains

Question 28

What is the primary structure of proteins?

Answer 28

linear amino acid sequence by covalent peptide bonds (polypeptide chain)

Question 28

What is the secondary structure of proteins?

Answer 28

ordered 3-D arrangement in space of backbone atoms in polypeptide chain by hydrogen bonds

ex. alpha helices and beta sheets

Question 29

Why are alpha helices and beta sheets common structures in proteins?

Answer 29

Common secondary protein structures stabilized by hydrogen bonds formed between backbone atoms of amino acids

Question 30

What is the quaternary structure of proteins?

Answer 30

binding of different polypeptide chain/ multiple subunits and is stabilized by noncovalent forces

Question 31

What are protein domains?

Answer 31

Referred in tertiary structure
Segment of amino acids that can perform specific function/ job

Question 32

What are protein subunits?

Answer 32

One polypeptide chain in protein with quaternary structure

Question 33

What are disulfide bonds?

Answer 33

Disulfide bonds are covalent bonds between cysteine residues (S-S)

Question 34

What types of proteins have disulfide bonds?

Answer 34

Observed in proteins that are secreted by the cell and attached to the outer surface of plasma membrane

Question 35

Why are disulfide bonds important for protein structure?

Answer 35

Disulfide bonds stabilize protein structure and can combine different polypeptide chains

Question 36

What is a ligand?

Answer 36

Any substance that is bound by a protein

Question 37

What is a binding site?

Answer 37

cavity with amino acid side chains that bind to ligand

Question 38

How does a ligand interact with a binding site?

Answer 38

Binding site uses electrostatic interactions and hydrogen bonds to selectively bind to 1 ligand