Amino Acids, Peptides, and Proteins

Question 1

Proteins are

Answer 1

the main agents of biological function

Question 2

Amino Acids are the

Answer 2

basic building blocks of proteins

Question 3

There are more than ____ amino acids in nature

Answer 3

300

Question 4

How many amino acids are found in the human body?

Answer 4

20

Question 5

Most amino acids in the human body are made up of

Answer 5

a-L amino acids

Question 6

Amino Acid Structure:

Each amino acid has

Answer 6

an a-amino group
an a-carboxyl group
a hydrogen atom
a specific side chain (R group) bonded to the a-carbon atom

Question 7

Amino Acid Structure:

Each amino acid has

Answer 7

an a-amino group
an a-carboxyl group
a hydrogen atom
a specific side chain (R group) bonded to the a-carbon atom

Question 8

What is an alpha amino acid?

Answer 8

a compound containing an amino group, -NH2, and a carboxylic acid group, -COOH

Question 9

Where does the amino group attach in biologically important amino acids?

Answer 9

it’s attached to the carbon atom next door to the COOH group

Question 10

What are alpha amino acids known as?

Answer 10

2-amino acids

Question 11

What are the 2 stereoiwsomers of alanine ?

Answer 11

L- and D-alanine

Question 12

How are amino acids classified?

Answer 12

side chain (R-group) classification 
solubility classification
metabolic classification
nutritional classification

Question 13

The structure of the R-group dictates

Answer 13

the chemical properties of the amino acid

Question 14

Classification by the structure of R includes:

Answer 14

-aliphatic (5)
aromatic (3)
psitively charged (3)
negatively charged (2)
amino acids derived from acidic amino acids (2)
sulfur containing amino acids (2)
hydroxyl-containing amino acids (3)
iminio acid (1)

Question 15

Examples of aliphatic amino acids

Answer 15

glycine
alanine 
valine 
leucine
isoleucine

Question 16

Glycine has unique properties because

Answer 16

its R group is just hydrogen

Question 17

All amino acids are chiral except

Answer 17

glycine

Question 18

How is glycine’s side chain unique?

Answer 18

the side chain is smaller than all others, which allows greater conformational flexibility than other amino acids

Question 19

Examples of Aromatic Amino Acids

Answer 19

phenylalanine
tyrosine
tryptophan

Question 20

Examples of Aromatic Amino Acids

Answer 20

phenylalanine
tyrosine
tryptophan

Question 21

Acidic amino acids
R group=
Donates __
_________ charged

Answer 21

carboxylic acid
H+
negatively

Question 22

Basic amino acids
R group=
Accepts __
_________ charged

Answer 22

amine
H+
positively

Question 23

Examples of negatively charged R-groups

Answer 23

asparatate

glutamate

Question 24

Examples of positively charged R groups

Answer 24

Lysine
Arginine
Histidine

Question 25

Examples of sulfur-containing amino acid R-groups

Answer 25

cysteine | methionine

Question 26

Examples of OH-containing amino acids (R-groups)

Answer 26

serine threonine tyrosine

Question 27

Derivatives of acidic amino acids include:

Answer 27

asparagine | glutamine

Question 28

Proline is unique due to

Answer 28

it's cyclic structure (no free rotation)

Question 29

Solubility in water classification

Answer 29

hydrophilic amino acids | hydrophobic amino acids

Question 30

Hydrophilic amino acids

Answer 30

polar, dissolve in water

Question 31

Hydrophobic amino acids

Answer 31

nonpolar, don't dissolve in water

Question 32

Name all proteins in the hydrophobic (non-polar) R-group | hint: GAL VIMP

Answer 32

``` glycine alanine leucine valine isoleucine methionine proline ```

Question 33

Name all the proteins in the hydrophilic (polar) R-group- uncharged hint: STAGC

Answer 33

``` Serine Threonine Aspargine Glutamine Cysteine ```

Question 34

Name all the proteins in the hydrophilic (polar) R-group- positively charged LAH

Answer 34

lysine arginine histidine

Question 35

Name all the proteins in the hydrophillic (polar) R-group-negatively charged hint: AG

Answer 35

aspartic acid | glutamic acid

Question 35

Name all the proteins in the hydrophillic (polar) R-group-negatively charged hint: AG

Answer 35

aspartic acid | glutamic acid

Question 36

Name all the proteins in the hydrophilic (polar) R-group- aromatic R-group hint: TPT

Answer 36

tyrosine phenylalanine tryptophan

Question 37

Name one characteristic of the Nonpolar, aliphatic R group

Answer 37

the amino acids in this group lack polar functional groups in their side chains

Question 38

Due to the _______ of their R groups, they often cluster together within the interior of proteins, ________ protein structure via _________ ________.

Answer 38

hydrophobicity, stabilizing, hydrophobic interactions

Question 39

The side-chains of the aromatic amino acids, overall are very _______.

Answer 39

hydrophobic

Question 40

The R group of _______ also contains a polar _______ group that can participate in __ ________ interactions.

Answer 40

tyrosine, hydroxyl, H bonding

Question 41

Polar, uncharged R groups: These amino acids side chains can form ________ _______.

Answer 41

hydrogen bonds

Question 42

Cytesine can form ________ _____.

Answer 42

disulfide bonds

Question 43

The R groups of the polar, uncharged amino acids all contain _____ _______ groups that can _______ _______ with water.

Answer 43

polar functional | hydrogen bond

Question 44

Serine and threonine contain

Answer 44

hydroxyl groups

Question 45

Asparagine and glutamine contain

Answer 45

amide groups

Question 46

Cystesine contains a __________ group.

Answer 46

sulfhydryl

Question 47

The ______ groups of 2 cysteine residues are readily _______ to form a _________ linked dimeric amino acid known as cystine.

Answer 47

thiol oxidized covalently

Question 48

In proteins, disulfide bonds form ______ links between different parts of a _________ chain or between 2 different ________ chains.

Answer 48

covalent, polypeptide, poplypeptide

Question 49

The disulfide-linked cystine residue is strongly

Answer 49

hydrophobic

Question 50

Metabolic classification includes

Answer 50

glucogenic amino acids purely ketogenic amino acids mixed amino acids

Question 51

Glucogenic amino acids

Answer 51

these amino acids could give intermediates which can finally give glucose

Question 52

Purely ketogenic amino acids

Answer 52

they give ketone bodies after its degradation in the body, but not glucose

Question 53

The only ketogenic amino acids are

Answer 53

leucine and lysine

Question 54

Mixed Amino Acids

Answer 54

These are amino acids that can give both ketone bodies and glucose intermediates.

Question 55

The mixed amino acids are

Answer 55

PTILT | phenylalanine, tyrosine, isoleucine, lysine, and tryptophan

Question 56

Other than PTILT, the rest of amino acids are all purely

Answer 56

glucogenic

Question 57

Nutritional classification of amino acids includes:

Answer 57

essential amino acids and non-essential amino acids

Question 58

Essential amino acids

Answer 58

are not synthesized in the body

Question 59

Non-essential amino acids are

Answer 59

synthesized in the body

Question 60

How many essential amino acids are there?

Answer 60

10 amino acids are not synthesized by the body

Question 61

The 10 amino acids that must be obtained from the diet are:

Answer 61

``` PVT Tim Hall phenylalanine valine tryptophan threonine isoleucine methionine histidine arginine leucine lysine ```

Question 62

Non-essential amino acids | hint: AAAACGGGPST

Answer 62

``` alanine arginine asparagine aspartic acid cysteine glutamic acid glutamine glycine proline serine tyrosine ```

Question 63

What are partially essential or semi-essential amino acids?

Answer 63

amino acids that growing children require (in food) but are not essential for an adult

Question 64

Name 2 semi-indispensable amino acids:

Answer 64

histidine | arginine