Bio test #1 Grade 10

Question 1

formula for hydrogen peroxide

Answer 1

2H2 O2 -> 2H2 O + O2

Question 2

catalase function

Answer 2

enzyme in potato that acts as a catalyst in hydrogen peroxide breakdown. hydrogen peroxide breaks into water and oxygen

Question 3

what does it mean to be a catalyst and how do enzymes work as catalysts

Answer 3

speed up rate of reaction without being consumed

enzymes are biological catalysts and can catalyze a large amount of substrate

Question 4

what are biological catalysts made of

Answer 4

proteins

Question 5

enzyme specificity

Answer 5

each type of enzyme is specific for only one kind of reaction

Question 6

lock and key model

Answer 6

described how certain substrates and enzymes share complementary shapes and therefore fit together allowing the reaction to take place

Question 7

active site

Answer 7

area on enzyme where the reaction takes place

Question 8

what happens with extreme heat treatment

Answer 8

the active sight on the enzyme gets destroyed, therefore limiting its effectiveness in catalyzing the reaction

Question 9

where does the enzyme go on the equation

Answer 9

over the arrow

Question 10

what happens when substrates enter the active site

Answer 10

the substrate binds (weak, temporary, chemical bond) to the active site. This allows the enzyme to catalyze the reaction. Chemical bonds are broken and formed and the products are released

Question 11

what is the enzyme substrate complex

Answer 11

the temporary molecule formed when the substrate binds to the enzyme (diagram of enzyme and substrate fit/bonded together)

Question 12

features that determine if the active site matches with the substrate include

Answer 12

complementary physical shape
complementary chemical properties (opposites attract)

Question 13

how do the enzyme and substrate fit together correctly for the reaction to occur

Answer 13

random particle motion.
at the atomic scale, particles move very wu only so even with a low probability, the correct configuration will occur often

Question 14

temperature

Answer 14

average particle speed: the higher the speed the greater the temperature the higher the kinetic or thermal energy.

Question 15

rate

Answer 15

speed/duration/change in x over time

Question 16

how to find rate

Answer 16

product produced over time
reactants consumed over time

Question 17

what is required for a chemical reaction to take place

Answer 17

reactant particles have to collide with sufficient kinetic energy and correct orientation

Question 18

optimum temperature

Answer 18

the highest temperature that the solution can be heated to before the active site of the enzyme gets denatured

Question 19

why does the rate of reaction increase as temperature does (until the optimum temp)

Answer 19

increase in temp represents an increase in particle speeds. higher particle speeds raise the probability that the collisions between particles result in successful reactions

Question 20

after optimum temp why does reaction rate decrease as temp increases

Answer 20

as a result of denaturation, the substrates ability to bind to the active site will be reduced or eliminated.

Question 21

what are enzymes made of and how are they held together

Answer 21

enzymes are proteins made up of amino acids. neighboring amino acids are joined together by covalent bonds (strong). in the locations where distant parts of the protein overlap, weaker chemical bonds (hydrogen bonds or ionic bonds) connect now neighboring amino acids. this maintains the shape.

Question 22

denaturation temp

Answer 22

at high temperature, the increased particle speeds cause some of the hydrogen bonds to break. this results in the change of structure/shape of the enzyme active site.

Question 23

denaturation pH

Answer 23

Acidic and alkaline pH’s effectively “neutralize” some of the hydrogen bonds that maintain the 3-D structure of the enzyme, resulting in denaturation.

Question 24

ion

Answer 24

molecule or atom that has gained or lost an electron

Question 25

ionization

Answer 25

H2O can separate into H+ and OH- (a hydrogen ion and a hydroxide ion)

Question 26

why does ionization occur

Answer 26

because chemical bonds are not infinitely strong

Question 27

what is the ratio of concentration when pure water molecule ionizes and how can it be shown

Answer 27

when one water molecule ionizes you get exactly one H+ and one OH-

shown with brackets

Question 28

what happens when HCL is added to pure water

Answer 28

HCL ionizes as well, creating H+ and CL-. this caused an excess of H+

Question 29

what are acids

Answer 29

an acid is a substance added to water that causes an excess of H+

Question 30

what are alkalines

Answer 30

alkali are substances added to water that create an excess of OH-

Question 31

what happens when NaOH is added to pure water

Answer 31

NaOH ionizes creating an excess of OH-

Question 32

why does rate of reaction decrease with both alkaline and acidic pH

Answer 32

because the acidity/alkaline causes the enzyme to denature

Question 33

low temp =

Answer 33

insufficient particle speeds

Question 34

high temp =

Answer 34

denaturation due to the rapid particle speeds that hit the bonds and break them

Question 35

acidic pH causes

Answer 35

denaturation

Question 36

alkaline pH causes

Answer 36

denaturation

Question 37

optimum temp for enzymes in humans is

Answer 37

37.5 degrees

Question 38

optimum pH for enzymes is

Answer 38

7 (neutral)

Question 39

how to draw graphs

Answer 39

temo/pH on the bottom
rate of reaction on the side

Question 40

ideal temp for plant or fungal enzymes

Answer 40

20 degrees

Question 41

industry enzymes ideal temp

Answer 41

90 degrees

Question 42

enzymes in the stomach ideal pH

Answer 42

acidic (1.5)

Question 43

Why is pH important to our health

Answer 43

having a stable pH is key to maintaining the body’s everyday functioning. The body is (usually) naturally able to maintain correct pH on its own

Question 44

How does denaturation due to acidic pH work

Answer 44

Excess H+ in the solution bond with the negatively charged amino acids (that were previously bonded to the positively charged non neighboring amino acids). This breaks the hydrogen bonds and changes the enzymes structure (Namely the active site)

Question 45

How does denaturation due to alkaline pH work

Answer 45

Excess OH- in the solution bond with the positively charged amino acids (that were previously bonded to the negatively charged non neighboring amino acids). This breaks the hydrogen bonds and changes the enzymes structure (Namely the active site)

Question 46

What are hydrogen bonds

Answer 46

occurs when there is a charge difference/charge interaction, where + and - charged amino acids interact

Question 47

What bonds connect neighboring and non neighboring amino acids

Answer 47

non neighboring - hydrogen bonds
neighboring - covalent bonds

Question 48

is denaturation a gradual or immediate process

Answer 48

denaturation can be a partial process. the gradual aspect is due to the amount of bonds (involved with maintaining the enzyme’s structure) are broken. The more damage, the less effective the enzyme is, and the slower the reaction rate is

Question 49

draw the enzyme substrate complex

Answer 49

two shapes with complementary areas that can fit in together

Question 50

what is pH

Answer 50

pH describes the relative concentrations of H+ and OH- in an aqueous solution

Question 51

extracellular enzymes and examples

Answer 51

Many enzymes function outside of cells to participate in reactions for the organism as a whole. Digestive enzymes are good examples of extracellular enzymes. Amylase is a digestive eynzme present in the saliva.