Test 2 Chemistry of Life part 2

Question 1

tertiary structure proteins

Answer 1

Overall three-dimensional shape of a polypeptide
Describing what a knot looks like from the outside

Question 2

quarternary structure proteins

Answer 2

When more than one polypeptide comes together to make an
even larger molecule
Like several completed knots glued together

Question 3

how important are enzymes?

Answer 3

All chemical reactions in living organisms require enzymes to work
Building molecules
Synthesis enzymes
Breaking down molecules
Digestive enzymes
Enzymes speed up reactions
Catalysts

Question 4

enzyme info

Answer 4

Enzymes are proteins
Each enzyme is the specific helper to
a specific reaction
each enzyme needs to be the right shape
for the job
enzymes are named for the reaction
they help
sucrase breaks down sucrose
proteases breakdown proteins
lipases breakdown lipids
DNA polymerase builds DNA

Question 5

enzymes aren’t used up

Answer 5

Enzymes are not changed by the reaction
used only temporarily
re-used again for the same reaction with other molecules
very little enzyme needed to help in many reactions

Question 6

lock and key model

Answer 6

specific enzyme for each specific reaction

the enzyme’s active site and the shape of the substrate molecule are complementary to one another. This allows the substrate to fit into the enzyme, like how a key would fit into a lock. If the substrate doesn’t fit, then the enzyme will not act on it

Question 7

peptide bond

Answer 7

A type of covalent bond which is formed by joining the carboxyl group of one amino acid to the amino group of another

Question 8

enzyme

Answer 8

Proteins that act as biological catalysts

Question 9

catalyst

Answer 9

A substance that speeds up the rate of a chemical reaction

Question 10

substrate

Answer 10

The reactants of an enzyme-based reaction

Question 11

active site

Answer 11

A site on an enzyme to which substrates bind

Question 12

what affects enzyme action

Answer 12

Correct protein structure
correct order of amino acids
Temperature
pH (acids & bases)

Question 13

enzymes - temp

Answer 13

Optimum temperature
greatest number of collisions between enzyme & substrate
human enzymes: 35°- 40°C (body temp = 37°C)
Raise temperature (boiling)
denature protein = unfold = lose shape
Lower temperature T°
molecules move slower
fewer collisions between enzyme & substrate

Question 14

enzymes - order of amino acids

Question 15

enzymes - pH

Answer 15

Effect on rates of enzyme activity
changes in pH changes protein shape
most human enzymes = pH 6-8
depends on where in body
pepsin (stomach) = pH 3
trypsin (small intestines) = pH 8

Question 16

what determines protein shape?

Answer 16

the sequence of amino acids within the protein