Week3-Course2

Question 1

Complete the following : Proteins are ____ linked by ____

Answer 1

polymers of amino acids

peptide bonds

Question 2

How is called the central carbon of proteins?

Answer 2

alpha carbon

Question 3

What are the two functional groups that are bonded to the alpha carbon

Answer 3

an amino group (-NH2) and a
carboxylic group (–COOH).

Question 4

Complete the following : the _____ group acts as an acid and the _____ group acts as a base

Answer 4

carboxyl

amine

Question 5

How many common amino acids is there

Answer 5

20

Question 6

What is the molecular formula of a.a

Answer 6

H2NCHRCOOH

Question 7

Side chains can be :

Answer 7

nonpolar
uncharged polar
positively charged
or negatively charged

Question 8

____ are less soluble in water and are attracted to other nonpolar compounds, such as lipids and cholesterol

Answer 8

Nonpolar side chains

Question 9

Amino acids with _____ will form hydrogen bonds and are attracted to other polar molecules, such as water

Answer 9

neutral polar side chains

Question 10

Positively charged aa tends to have a high degree of ____ group

Answer 10

amino

Question 11

Negative aa tends to have a high degree of ____ group

Answer 11

carboxylic

Question 12

What do we mean by essential amino acids?

Answer 12

that cannot be synthesized or that are not synthesized in sufficient amounts by the body to meet its protein synthesis

Question 13

How many essential amino acids is there?

Answer 13

9

Question 14

What are the 9 essential amino acids

Answer 14

1-histidine
2-isoleucine
3-leucine
4-lysine
5-methionine
6-phenylalanine
7-threonine
8-tryptophan
9-valine

Question 15

What is the mnemonic to remember the essential amino acids

Answer 15

These ....... Tryptophan
Ten ......... Threonine
Valuable .... Valine
Amino Acids . Arginine*** 
Have ........ Histidine
Long ........ Lysine
Preserved ... Phenylalanine
Life ........ Leucine
In .......... Isoleucine
Man ......... Methionine
***semi-essential not in the ppt

Question 16

What are complete proteins?

Answer 16

protein that contains all the essential amino acids

Question 17

____ structure is the sequence of amino acids in the polypeptide chain.

Answer 17

primary

Question 18

what are the two types of hydrogen bonded structure that a.a can form

Answer 18

1. alpha-helix

2. beta pleated sheet

Question 19

What is quaternary structure?

Answer 19

Three-dimensional arrangement of multi-subunit proteins

Question 20

What is tertiary structure?

Answer 20

The full three-dimensional structure of a protein molecule

Question 21

T or F : proteins often contain sulfur

Answer 21

true