PRELIM 02 - Proteins

Question 1

Are polymers of amino acids

Answer 1

Proteins

Question 2

Are molecules that contains an amino, carboxyl, and side chain group

Answer 2

Amino acid

Question 3

A chemical group that gives identity to the amino acid

Answer 3

Side chain group (R)

Question 4

All amino acids, except __________ have at least one stereocenter and are achiral

Answer 4

Glycine

Question 5

Molecules that contain both positive and negative charges

Answer 5

Zwitterion

Question 6

Proton donor

Answer 6

Bronsted acid

Question 7

Proton acceptor

Answer 7

Bronsted base

Question 8

The pH at which the net charge of an amino acid/peptide is zero

Answer 8

Isoelectric pH (pl)

Question 9

Is an amide bond between the α-carboxyl group of one amino acid and the α-amino group of another amino acid

Answer 9

Peptide bond

Question 10

Molecules that are two or more amino acids linked by peptide bonds

Answer 10

Peptides

Question 11

Are amino acids not or inadequately synthesized by the body; essential in the diet

Answer 11

Essential amino acids

Question 12

Are amino acids that can be synthesized in the body; not required in the diet

Answer 12

Non-essential amino acids

Question 13

Refers to the spatial arrangement of atoms in a protein

Answer 13

Conformation

Question 14

The three-dimensional structure of a protein is called __________

Answer 14

Native conformation

Question 15

Are proteins in any of their functional, folded conformation

Answer 15

Native proteins

Question 16

4 levels of protein organization

Answer 16

Primary, Secondary, Tertiary, Quaternary

Question 17

It refers to the sequence of amino acids in a polypeptide chain (Levels of protein organization)

Answer 17

Primary structure

Question 18

It refers to the ordered 3D arrangements in localized regions of a polypeptide chain (Levels of protein organization)

Answer 18

Secondary structure

Question 19

3 types of secondary structure of proteins

Answer 19

α-Helix, β-sheet, Random coil

Question 20

Spiral structure; stabilized by intramolecular hydrogen bonds (Types of secondary structure of proteins)

Answer 20

α-Helix

Question 21

Pitch of α-Helix

Answer 21

5.4 Angstrom

Question 22

It is formed when 2 or more polypeptides line up side by side (Types of secondary structures of proteins)

Answer 22

β-sheet/β-pleated sheet

Question 23

2 types of β-sheets/β-pleated sheets

Answer 23

Anti-parallel β-sheet, Parallel β-sheet

Question 24

These are non-repetitive structures; an irregular or unique conformation (Types of secondary structures of proteins)

Answer 24

Random coils

Question 25

Are structures that are combinations of α and β-strands

Answer 25

Supersecondary structures

Question 26

4 examples of supersecondary structures

Answer 26

βαβ unit, αα unit, β-meander, Greek key

Question 27

It refers to the three-dimensional conformation of the entire polypeptide (Levels of protein organization)

Answer 27

Tertiary structure

Question 28

Are proteins composed of a polypeptide chain arranged in long strands or sheets

Answer 28

Fibrous proteins

Question 29

2 examples of fibrous proteins

Answer 29

Collagen, Keratin

Question 30

Are proteins composed of a polypeptide chain folded into compact, spherical structure

Answer 30

Globular proteins

Question 31

2 examples of globular proteins

Answer 31

Enzymes, Hemoglobin

Question 32

It refers to the spatial arrangement of polypeptide subunits (Levels of protein organization)

Answer 32

Quaternary structure

Question 33

Quaternary structure with 2 subunits

Answer 33

Dimer

Question 34

Quaternary structure with 3 subunits

Answer 34

Trimer

Question 35

Quaternary structure with 4 subunits

Answer 35

Tetramer

Question 36

2 examples of glucose homeostatic proteins; they control carbohydrate metabolism by binding on specific receptors

Answer 36

Insulin, Glucagon

Question 37

Insulin and glucagon are synthesized at the __________

Answer 37

Pancreas

Question 38

Insulin is synthesized at __________

Answer 38

β-cells

Question 39

Glucagon is synthesized at __________

Answer 39

α-cells

Question 40

Hormone of nutrient abundance; a protein hormone consisting of two amino acid chains linked by disulfide bonds

Answer 40

Insulin

Question 41

3 major targets for insulin

Answer 41

Liver, Skeletal muscle, Adipose tissue

Question 42

A 29-amino acid polypeptide hormone that is a potent hyperglycemic agent

Answer 42

Glucagon

Question 43

Refers to the breakdown of glycogen to glucose

Answer 43

Glycogenolysis

Question 44

Refers to the synthesis of glucose from lactic acid and non-carbohydrates

Answer 44

Gluconeogenesis

Question 45

2 examples of hemeproteins

Answer 45

Hemoglobin, Myoglobin

Question 46

Hemoglobin's major role is __________

Answer 46

Oxygen transport

Question 47

Myoglobin's major role is __________

Answer 47

Oxygen storage

Question 48

Tetramer of hemoglobin

Answer 48

α2β2

Question 49

Other name for immunoglobulin; is a y-shaped molecule produced by B-cells during adaptive immune response

Answer 49

Antibodies

Question 50

Immunoglobulin is composed of __________ subunits; __________ heavy chains and __________ light chains

Answer 50

4 subunits, 2 heavy chains, 2 light chains

Question 51

Immunoglobulin is composed of: __________, __________, and __________

Answer 51

Constant regions, Variable regions, Hinge

Question 52

5 antibody isotypes

Answer 52

IgM, IgA, IgD, IgG, IgE

Question 53

The antibody which serves as protection for primary infections

Answer 53

IgM

Question 54

The antibody that is commonly found in human secretions like tears, mucous, and saliva

Answer 54

IgA

Question 55

The cell attached antibody which function is still under study

Answer 55

IgD

Question 56

The most dominant antibody in humans; this antibody is responsible for secondary immune response

Answer 56

IgG

Question 57

The antibody responsible for allergic reactions

Answer 57

IgE

Question 58

It refers to the disruption of the protein conformation as well as its function

Answer 58

Denaturation