Protein

Question 1

are macromolecules made of amino acids, with each amino acid being linked to another via a peptide bond.

Answer 1

Proteins

Question 2

proteins can bear positive & negative charges

Answer 2

amphoteric

Question 3

synthesized in the liver & secreted by the hepatocyte
into the circulation EXCEPT immunoglobulins

Answer 3

plasma cells

Question 4

provide ________ of the total daily body energy
requirement

Answer 4

12 – 20%

Question 5

composes __________ of the cell’s dry weight

Answer 5

50 – 70%

Question 6

is formed when the carboxyl (-COOH) group of one amino acid links to the amino (-NH2) group of another amino acid with the loss of a water molecule.

Answer 6

Peptide bond

Question 7

End of protein structure with a free amino group

Answer 7

N-terminal

Question 8

End of protein structure with a free carboxyl group

Answer 8

C-terminal

Question 9

Proteins consist of 16% nitrogen, which differentiates proteins from carbohydrates and lipids.

Answer 9

Nitrogen content

Question 10

Structure of an Amino Acid

Answer 10

Peptide bond
N-terminal
C-terminal
Nitrogen content

Question 11

maintenance of water distribution between cells and tissue, interstitial compartments, and the vascular system of the body(________)

Answer 11

Osmotic force
Albumin

Question 12

participation as buffers to maintain pH

Answer 12

Acid-base balance

Question 13

metabolic substances (Albumin, Haptoglobin, Transferrin)

Answer 13

Transport
(Albumin, Haptoglobin, Transferrin)

Question 14

part of immune defense system (________________/ _________________)

Answer 14

Antibodies
(Gammaglobulins/ Immunoglobulins)

Question 15

Five major classes of antibodies

Answer 15

IgA, IgD, IgE, IgG, and IgM

Question 16

Synthesized in plasma cells as an immune response

Answer 16

Antibodies

Question 17

______________ and receptors (Peptide hormones: Insulin, glucagon, thyrocalcitonin, pituitary hormones (GH, PTH, PRL), and hypothalamic (ADH, oxytocin, thyrotropin releasing
hormones)

Answer 17

Hormones

Question 18

Peptide hormones

Answer 18

Insulin, glucagon, thyrocalcitonin, pituitary hormones, hypothalamic

Question 19

3 pituitary hormones

Answer 19

Growth Hormone (GH), Pituitary Hormone (PTH), Prolactin (PRL)

Question 20

3 hypothalamic

Answer 20

ADH, oxytocin, thyrotropin releasing hormones

Question 21

connective tissue (___________, _______, ____________)

Answer 21

Structure
(collagen, keratin, elastic fibers)

Question 22

catalysts (_______________, _________, _______________)

Answer 22

Enzymes
(Dehydrogenases, kinase, phosphatase)

Question 23

participation in coagulation of blood (____________)

Answer 23

Hemostasis
(Fibrinogen)

Question 24

Proteins can be broken down into amino acids that can be used in the citric acid cycle to produce energy.

Answer 24

Energy

Question 25

- linear sequence of the AA − basis for differentiation − analytical processes : ______________, _______________, _____________and ____________________

Answer 25

Primary Structure (chromatography, electrophoresis, dye binding and light absorbance depend on this sequence)

Question 26

refers to the specific regular recurring arrangement in space of the primary structure extending along one dimension

Answer 26

Secondary structure

Question 27

three structures : (dependent on numerous hydrogen bonds and occasional disulfide covalent bonds)

Answer 27

alpha-helix, beta-pleated sheets, random coils

Question 28

chain forms a regular helix ; coil resembling a spring

Answer 28

alpha-helix

Question 29

in fully extended structures; flat, corrugated structure

Answer 29

beta-pleated sheets

Question 30

no apparent pattern

Answer 30

random coils

Question 31

actual 3-dimensional structure or folding pattern of the protein, uniquely determined by its AA sequence leading to a specific shape

Answer 31

Tertiary structure

Question 32

Tertiary structure is maintained by ______________________, ______________, _________________ (_______________) and _____________________

Answer 32

electrovalent linkages, hydrogen bonds, disulfide bridges (covalent disulfide) and hydrophobic interactions

Question 33

combination of subunits

Answer 33

Quaternary structure

Question 34

- association of several polypeptide chains into larger “oligomeric” aggregate unit - stable complexes : ______, _______, _________

Answer 34

Quaternary structure (dimers, trimers, tetramers)

Question 35

chemically react as either acid or base

Answer 35

Amphoteric

Question 36

readily modified in solution when subjected to alterations in pH, UVR, heat and organic solvents

Answer 36

Labile

Question 37

_______________ & _______________ due to the presence of side chains & active NH2 groups

Answer 37

Very reactive & highly specific

Question 38

3 Solubility

Answer 38

neutral salt, pH, organic solvents

Question 39

low salt concentration increases solubility of CHONs

Answer 39

Salting in

Question 40

high salt level concentration decreases solubility of CHONs

Answer 40

Salting out

Question 41

In metallic poisoning, __________ and ____ will precipitate the metals

Answer 41

egg white and milk

Question 42

solubility is minimum at isoelectric point (when molecule has the no net charge) and solubility rises with increasing acidity or alkalinity

Answer 42

pH

Question 43

decreases solubility

Answer 43

Organic solvents

Question 44

Selective separation of the constituent proteins of a mixture can be achieved by proper adjustment of __, _______________, __________________________, _________________ and __________________ kept at low level.

Answer 44

Fractionation (pH, temperature, alcohol concentration, protein concentration and salt concentration)

Question 45

2 Action of heat

Answer 45

Denaturation, Coagulation

Question 46

proteins undergo slight intramolecular rearrangements when they are heated between _________ (_____________)

Answer 46

Denaturation 40 – 50° (reversible)

Question 47

linkage of adjacent protein molecules by means of Hydrogen bonds (further heating will cause _______________ damage)

Answer 47

Coagulation (irreversible)

Question 48

3 Precipitation

Answer 48

By acids, By salts of heavy metals, By alcohol

Question 49

negative charged acids neutralizes the positively charge proteins formation of insoluble salts

Answer 49

By acids

Question 50

formation of insoluble salts

Answer 50

By salts of heavy metals

Question 51

Example salts of heavy metals

Answer 51

(alkali metals; Hg, Ag and Pb)

Question 52

precipitation occurs as isoelectric point

Answer 52

By alcohol (dehydration)

Question 53

Alcohol precipitates bacteria (antiseptic property) at ___

Answer 53

70%