Unit 3 (metabolism and enzymes)

Question 1

What is metabolism

Answer 1

chemical reactions of life

Question 2

chemical reactions of life

Answer 2

metabolism

Question 3

Describe anabolic reactions

Answer 3

forming bonds between molecules

Question 4

describe catabolic reactions

Answer 4

breaking bonds between molecules

Question 5

describe chemical reactions which release energy

Answer 5

• exergonic
• digesting
• hydrolysis= catabolism

Question 6

hydrolysis=?

Answer 6

catabolism

Question 7

what is an exergonic chemical reaction

Answer 7

a chemical reaction that releases energy

Question 8

Describe chemical reactions that require input of energy

Answer 8

• endergonic
• building
• dehydration synthesis=anabolism

Question 9

dehydration synthesis=?

Answer 9

anabolism

Question 10

where do exergonic and endergonic reactions occur

Answer 10

in cells

Question 11

What is activation energy

Answer 11

amount of energy needed to destabilize the bonds of a molecule

Question 12

Why is activation energy needed

Answer 12

• breaking down large molecules requires initial input of energy
• large molecules are stable
• must absorb energy to break bonds

Question 13

What reduces activation energy

Answer 13

catalysts

Question 14

what is a catalyst

Answer 14

a chemical to reduce amount of activation energy needed to start reaction

Question 15

why do cells use enzymes

Answer 15

to reduce energy

Question 16

what is an enzyme

Answer 16

biological catalyst

Question 17

What is the substrate

Answer 17

reactant which bonds to active site of enzyme

Question 18

what is the active site

Answer 18

enzymes’ catalytic site; substrate fills into it

Question 19

What are the properties of enzymes

Answer 19

reaction specific
affected by cellular conditions
are not consumed in reaction

Question 20

how are enzymes reaction specific

Answer 20

each enzyme works with a specific substrate

there is a chemical fit between active site and substrate

Question 21

Explain how enzymes are not consumed in chemical reactions

Answer 21

single enzyme molecule can go through thousands or more

they are unaffected by reaction

Question 22

Describe the lock and key model

Answer 22

simplistic model

substrate goes into active site

Question 23

Describe the induced fit model

Answer 23

• more accurate model

- substrate bonding causes enzyme to change shape

Question 24

which enzyme model shows confirmation change

Answer 24

induced fit model

Question 25

describe what happens when an enzyme creates synthesis

Answer 25

- active site orients substrate in correct reaction position - enzymes bring substrate closer together

Question 26

describe what happens when an enzyme creates digestion

Answer 26

- active site binds substrate and put stress on bonds that must be broken - makes it easier to separate molecules

Question 27

Explain how enzyme concentration effects the enzyme function

Answer 27

- more collisions with substrate | - reaction rate levels off

Question 28

why does the reaction rate level off with enzyme concentration

Answer 28

- substrate becomes limited | - not all enzymes can find substrate

Question 29

explain how substrate concentration effects the enzyme function

Answer 29

- more collisions with enzymes | - reaction rate levels off

Question 30

why does the reaction rate level off with substrate concentration

Answer 30

all enzymes action sites are engaged (saturated)

Question 31

Explain how temperature effects the enzyme function

Answer 31

- optimum temperature= greatest amount of molecular collisions - denaturation

Question 32

explain how ph effects the enzyme function

Answer 32

- disrupts h bonds - denatures - adds ions

Question 33

explain hoe salinity effects the enzyme function

Answer 33

- disrupts h bonds - denatures proteins - adds ions - enzymes are intolerant of extreme salinity