Proteins

Question 1

What are proteins composed of?

Answer 1

Amino acids

Question 2

How are amino acids composed?

Answer 2

An amino group to the left, carbonyl group on the right, with a CH in the middle called the alpha carbon

The only difference is there r group therefore it’s used to identify them

Question 3

Where does proteins building stem from?

Answer 3

Amino acids

Question 4

What are proteins?

Answer 4

These are amino acids joined together by polypeptides

Most diverse and most important molecule in living organisms

Question 5

What are the functions of proteins?

Answer 5

Structural building blocks

Cellular functions (immune defence, cell to cell transport, oxygen transport)

Genetic operations (growth, repair, and protection)

make enzymes
make hormones
build and maintain tissue

In emergency or starvation they can be broken down or used as an energy source

Question 6

What does the iodized amino acid look like?

Answer 6

N+ O-

Question 7

non polar

Answer 7

R group is a hydrocarbon structure

If sulphur or hydrogen is present it is within the group (not at the bottom)

Electrons are shared relatively equally

Question 8

Polar

Answer 8

The R groups contains sulphur, nitrogen, and/or oxygen

These elements have a higher electronegativity and draw electrons to them resulting in a polar molecule
(But no overall charge is present in the r group)

Question 9

Electrically Charges Acidic

Answer 9

lost H+ ions in the solution, therefore R group is left with negatively charged

Question 10

Basic

Answer 10

accept H ions from the solution, therefore R group is left with a positive charge

Question 11

what is the SNO rule for polarity?

Answer 11

if the R group contains a sulphur, nitrogen, or oxygen then it is polar

Question 12

what makes an amino acids positive or negatively charged?

Answer 12

if it loses H+ ions in the solution, then it is negative=acidic

if it gains H+ ions in the solution, then it is positive=basic

Question 13

what are the eight essential amino acids

Answer 13

must be obtained through the diet
Isoleusine
leucine
Lysine
methionine
phenylalanine
threonine
tryptophan
valine

Question 14

complete protein

Answer 14

food that has full set of all 8 essential amino acids

these foods include animal meat such as red meat, pork, and fish

Question 15

what is an amide linkage?

Answer 15

this is a carbon to nitrogen bond

Question 16

what is the first level of protein folding and what is it known for?

Answer 16

this is called primary,

this is a chain of 50 amino acids linked by peptide bonds

the type of amino acids present or the sequence itself, varied from molecule to molecule

amide linkages are formed between an NH2 (amino group) and a COOH (carboxyl group)

Question 17

what is the second level of protein folding and what is it known for?

Answer 17

this is called secondary,

coiling stages in two ways, alpha helix, and beta pleated sheets

consists of interactions with the polypeptide backbone

Question 18

alpha helix vs beta sheets

Answer 18

alpha helix: two parts of a polypeptide chain are coiled together, hydrogen are always four amide linkages away between the carboxyl group and amino group

two parts of a polypeptide chain lie parallel, Hydrogens (the stabilizer) form between carbonyl and amino groups

Question 19

hydrophobic vs hydrophilic acid chains

Answer 19

hydrophobic has carbon rich side chain, doesn’t react well with water

hydrophilic molecules interact well with water

Question 20

what is the third level of protein folding and what is it known for?

Answer 20

this is called tertiary,

strong forces of attraction and repulsion between the polypeptide and its environment force it to undergo additional folding (stringy like hair follicles)

Hydrogens bond between the polar side

Ionic bonds between the oppositely charged side (acid/base)

Vander Waals forces between nonpolar side chains

Disulphide bridges between two cysteines (S-S) (strong stabilizers of tertiary structure

Proline Kinks

Question 21

what is a proline kink

Answer 21

naturally bends the alpha helix or beta-pleated sheets where needed

Question 22

what is the fourth level of protein folding and what is it known for?

Answer 22

this is called quaternary,

two or more polypeptide subunits must come together to form a functional protein

eg fibrous protein found in hair, hemoglobin

Question 23

denaturation

Answer 23

a change in the protein structure formation caused by temperature, ionic concentration, Ph, or environmental factors