enzymes

Question 1

what are enzymes made of

Answer 1

-large globular proteins

Question 2

when is energy released

Answer 2

-when large molecules undergo catabolic reactions in metabolic pathways

Question 3

what is the matabolism

Answer 3

-the sum of all the different anabolic and catabolic reactions and reaction pathways in a cell/organism as a result of enzymes

Question 4

what type of reactions do enzymes catalyse

Answer 4

-anabolic
-catabolic

Question 5

examples of anabolic reactions

Answer 5

-triglyceride synthesis
-protein synthesis
-photosynthesis

Question 6

examples of catabolic reactions

Answer 6

-respiration
-glycolysis
-lipolysis
-hydrolysis of ATP
-breakdown of polysaccharides like starch and glycogen into monosaccharides like glucose

Question 7

example of reaction that would not happen without an enzyme

Answer 7

-DNA replication, photosynthesis

Question 8

demo of temperature on enzymes

Answer 8

-Liver demo

Question 9

describe the liver demo

Answer 9

-in mammals, catalase is an intracellular enzyme produced primarily in the liver
-it breaks down toxic build up of hydrogen peroxide
-when liver is boiled and then laced into hydrogen peroxide, doesn’t react as the enzyme catalase has been denatured, it cant break down hydrogen peroxide into water and oxygen

Question 10

what are reactants in an intracellular enzyme known as

Answer 10

-metabolites

Question 11

catabolic vs anabolic

Answer 11

-catabolic breaks down
-anabolic synthesises larger molecules

Question 12

facts abt enzymes

Answer 12

-more specific than chemical catalysts
-don’t produce unwanted by products
-rarely make mistakes

Question 13

ways to increase rate of reaction

Answer 13

-increase pressure, temp, surface area, concentration
-use enzyme to lower activation energy

Question 14

example of a reaction that doesnt require enzymes

Answer 14

-peptide bond hydrolysis would happen anyway without an enzyme

Question 15

active site of an enzyme

Answer 15

-highly specific
-complementary to the shape of the corresponding substrate molecule

Question 16

what are the stages of enzymes

Answer 16

-enzyme + substrate
-enzyme substrate complex
-enzyme product complex
-enzyme + products

Question 17

how does the lock and key model work

Answer 17

-the substrate is held in a fixed position (causing R groups to interact) which pouts the atom groups close enough to react
-the R-groups in the active site interact with the substrate forming temporary bonds
-these bonds put strain on the substrate

Question 18

how does the induced fit model work

Answer 18

-initial weak interactions between the substrate and active site changes the tertiary structure of the enzyme, putting strain on the bonds in the substrate molecule
-the weakened bonds in the substrate are more likely to break causing a reaction to happen

Question 19

in the lock and key model what puts strain on the substrate

Answer 19

the position the substrate is held in

Question 20

in the induced fit model what puts strain on the substrate

Answer 20

-bonds formed as the substrate is approaching the active site

Question 21

what do bonds form between when the substrate binds to an enzyme?

Answer 21

-the substrate and the amino acids on surface of active site (R- Groups)

Question 22

what made scientists previously think the lock and key model was how enzymes worked?

Answer 22

-they thought the tertiary structure was fixed and the substrate slotted perfectly into it

Question 23

why wasn’t the lock and key model correct?

Answer 23

• as the substrate approaches and starts to form bonds w AA’s the tertiary structure of the active site changes and moulds to fit the substrate

Question 24

why can different substrates not bond to an enzyme

Answer 24

-they cant form the correct bonds w the AA’s on the active site and tertiary structure doesn’t change to fit it

Question 25

process of intracellular enzyme metabolic pathway

Answer 25

-enzymes which are used in the cell they’re made
-product of enzyme A is the substrate for enzyme B, etc
-each step of the metabolic pathway catalysed by different enzymes

Question 26

why do we need extracellular enzymes

Answer 26

-reactions within cells require raw materials in a constant supply to make new products needed by the organism
-these raw materials often enter body in polymers
-polymers too large to cross cell membrane so are catalysed by extracellular enzymes

Question 27

how do extracellular enzymes work

Answer 27

-secreted out of the cell where they’re made to act on substances extracellularly such as digestive enzymes like amylase and tripsin

Question 28

example of an organism which releases extracellular enzymes

Answer 28

fungi onto food and then absorb nutrients through hyphae