Proteins

Question 1

_____________ are the major structural and functional components of all cells in the body, and act to facilitate biochemical reactions among the most abundant biological macromolecules and are extremely versatile in their functions.

Answer 1

Proteins

Question 2

Proteins play a crucial role in a healthy, balanced diet. For example, without sufficient protein nutrition, we would not be able to form ________, and the body’s ability to repair and generate cells would be affected.

Answer 2

enzymes

Question 3

____________ percent of the human body is made up of proteins.

Answer 3

Twenty

Question 4

A typical human cell contains about __________ different kinds of proteins, and the human body contains about ________ different proteins.

Answer 4

9000, 100 000

Question 5

All proteins contain the elements _______, _________, __________, and __________; most also contain ______.

Answer 5

carbon, hydrogen, oxygen, nitrogen, sulfur

Question 6

Proteins are composed of ___________ carbon.

Answer 6

50-55%

Question 7

Proteins are composed of ___________ carbon.

Question 8

Proteins are composed of ___________ oxygen.

Answer 8

19-24%

Question 9

Proteins are composed of ___________ nitrogen.

Answer 9

13-19%

Question 10

Proteins are composed of ___________ sulfur.

Answer 10

0-4%

Question 11

The building blocks for Proteins

Answer 11

Amino acids

Question 12

It is a molecule that has both negative and positive charges

Answer 12

Zwitterion

Question 13

Amino acids are _____________ (able to react both as
a base and as an acid.)

Answer 13

amphoteric

Question 14

Amino acids naturally occur in ___ form

Answer 14

L

Question 15

It is a molecule that has a positive charge on
one atom and a negative charge on another atom, but
which has no net charge.

Answer 15

Zwitterion

Question 16

In an acidic solution, the zwitterion accepts a _________ to form a positively charged ion.

Answer 16

proton (H+
)

Question 17

In basic solution, the -NH3 of the zwitterion _______ a proton,
and a negatively charged species is formed.

Answer 17

loses

Question 18

___________ are the best-known examples of zwitterions.

Answer 18

Amino acids

Question 19

Classification of Amino Acids based on Side Chain (R groups)

Answer 19

1. Non polar aliphatic amino acids
   2.Amino acids with Uncharged (neutral) side chain
2. Acidic amino acids
   4.Amino acids with basic side chain

Question 20

Classification of Amino Acids Based on Capacity of the Body to Synthesize Them

Answer 20

1. Essential Amino acids
2. Non-essential amino acids

Question 21

There are _____ essential amino acids

Answer 21

nine

Question 22

There are ________ essential amino acids

Answer 22

eleven

Question 23

They cannot be synthesized in the body and, therefore, must be present in the diet in order for protein synthesis to occur.

Answer 23

Essential amino acids

Question 24

It is required for growth in children but is not an essential amino acids for adults

Answer 24

Arginine

Question 25

These amino acids can be synthesized in the body itself and hence not necessarily needed to be acquired through diet

Answer 25

Non-essential Amino Acids

Question 26

Amino acids are linked together in proteins by a special kind of bond

Answer 26

Peptide bonds

Question 27

Small Peptide Hormones

Answer 27

o Vasopressin o Oxytocin

Question 28

Small Peptide Neurotransmitters

Answer 28

Enkephalins

Question 29

Small Peptide Antioxidants

Answer 29

Glutathione

Question 30

___________ regulates the excretion of water by the kidneys; it also affects blood pressure

Answer 30

Vasopressin

Question 31

Another name for vasopressin is _________________

Answer 31

antidiuretic hormone (ADH)

Question 32

It is produced by the pituitary gland, and stimulates uterine contractions in labor.

Answer 32

Oxytocin

Question 33

It was the first naturally-occurring hormone to be produced in a laboratory.

Answer 33

Oxytocin

Question 34

Pentapeptide neutrotransmitters produced by the brain itself that bind at the receptor sites in the brain to reduce pain.

Answer 34

ENKEPHALINS

Question 35

Is present in significant concentrations in most cells and have physiological importance as a regulator of oxidation-reduction reactions. As anti-oxidants. Protecting cells contents form the oxidizing agents such as peroxides and superoxides.

Answer 35

Glutathione

Question 36

They are examples of chemical signaling peptides. They are natural painkillers that are produced in the body. They interact with receptors in the brain to inhibit the transmission of pain signals.

Answer 36

Endorphins

Question 37

___________ is a naturally occurring, extremely complex substance that consists of amino acid residues joined by peptide bonds

Answer 37

Protein

Question 38

4 PROTEIN STRUCTURAL LEVELS

Answer 38

•PRIMARY STRUCTURE •SECONDARY STRUCTURE •TERTIARY STRUCTURE •QUATERNARY STRUCTURE

Question 39

Is the order in which amino acids are linked together in a protein.

Answer 39

Primary Structure

Question 40

The hormone that regulates blood glucose levels

Answer 40

Insulin

Question 41

Is the arrangement in a space adopted by the backbone portion of protein.

Answer 41

Secondary structure

Question 42

The polypeptide chain is coiled tightly in the fashion of a spring

Answer 42

Alpha helix

Question 43

In this structure, individual protein chains are aligned side-by-side with every other protein chain aligned in an opposite direction. The protein chains are held together by intermolecular hydrogen bonding, that is hydrogen bonding between amide groups of two separate chains.

Answer 43

Beta pleated sheets

Question 44

Is the overall three dimensional structure shape of the protein that result from the interaction between amino acid side chains (R Groups).

Answer 44

Tertiary structure

Question 45

it is the strongest of the tertiary structure interactions result from the –SH groups. Of two cysteine residues interacting with each other forming

Answer 45

Covalent Disulfide

Question 46

Involves the interactions between the acidic side Groups and basic R group. The acidic being negative –COOH becomes –COO- The basic being positive –NH2 becomes NH3 +

Answer 46

Electrostatic interactions called salt bridges

Question 47

This can occur between amino acids with polar R groups.

Answer 47

Hydrogen bonds

Question 48

Results when 2 non polar amino acids are close with each other.

Answer 48

HYDROPHOBIC INTERACTIONS

Question 49

Highest level of protein organization. It is only found in multimeric proteins. Describes the interactions of the subunits in an oligomeric protein. Present also the electrostatic interactions Hydrogen bonds

Answer 49

Quaternary structure

Question 50

The sequence of amino acids present in a protein's peptide chain or chains

Answer 50

Primary Structure

Question 51

The regularly repeating ordered spatial arrangements of amino acids near each other in the protein chain, which result from hydrogen bonds between carbonyl oxygen atoms and amino hydrogen atoms

Answer 51

Secondary structure

Question 52

The overall three-dimensional shape that results from the attractive forces between amino acid side chains (R groups) that are not near each other in the protein chain

Answer 52

Tertiary structure

Question 53

The three-dimensional shape of a protein consisting of two or more independent peptide chains, which results from noncovalent interactions between R groups

Answer 53

Quaternary structure

Question 54

3 Main types of proteins

Answer 54

Fibrous, Globular, and Conjugated

Question 55

It is a protein whose molecules have an elongated shape with one dimension much longer than the others. They tend to have simple, regular, linear structures.

Answer 55

Fibrous proteins

Question 56

A __________ is a protein whose molecules have peptide chains that are folded into spherical or globular shapes.

Answer 56

globular protein

Question 57

These are simple proteins combined with some non-protein material in the body.

Answer 57

Conjugated proteins

Question 58

____________ is a structural change in a protein that results in the loss (usually permanent) of its biological properties

Answer 58

Denaturation

Question 59

Temperatures at which proteins denature may vary, but most human proteins function optimally at body temperature (~37ºC).

Answer 59

True