Internale Membranes & Enzymes (PPT 8) (U1)

Question 1

Define metabolism

Answer 1

• All the chemical reactions in a living thing.

Question 2

What are the two types of reactions?

Answer 2

• Anabolic

- Catabolic

Question 3

What is an Anabolic reaction?

Answer 3

Small molecules are combined to make larger molecules.

Energy is needed

Question 4

What is a Catabolic reaction?

Answer 4

Large molecules broken down into smaller molecules.

Energy is given out

Question 5

What are enzymes?

Answer 5

• Organic catalysts

- Proteins that can increase the rate a reaction occurs.

Question 6

How many levels of structure do proteins have and what are they?

Answer 6

• 4

- Primary, Secondary, Tertiary, and Quaternary structure.

Question 7

What is a primary structure?

Answer 7

Straight chains of AA bonded together by peptide bonds.

Question 8

What is a secondary structure?

Answer 8

Coiling or pleating due to hydrogen bonding.

Question 9

What is a tertiary structure?

Answer 9

3D folding due to bonding between attractions and repulsions between the special R group on each AA.

Question 10

What is a Quaternary structure?

Answer 10

Where two or more proteins form protein aggregates.

Question 11

What is the active site?

Answer 11

A cleft, groove or pocket on the surface of the enzyme that the substrate binds to.

Question 12

What is a substrate?

Answer 12

The substance that binds to the enzyme.

Question 13

Enzymes are ——- specific, this specificity —— from enzyme to ——-. (Fill in the blanks)

Answer 13

1- Substrate
2- varies
3- enzyme

Question 14

When a substrate binds to an enzymes active site, a what is formed?

Answer 14

An enzyme-substrate complex.

Question 15

What makes enzymes so substrate specific?

Answer 15

The complexity of the active site.

Question 16

How do enzymes work?

Answer 16

It weakens the existing bonds to create new ones. Creating a new product entirely.

Question 17

Do enzymes become apart of the reaction?

Answer 17

NO! They are simply facilitators. (Think of them like match makers)

Question 18

What is the lock and key model, and what does it include?

Answer 18

A theory on how enzymes work.

The substrate was drawn into a closely matching cleft on the enzyme.

Question 19

What is the Induced fit model, and what does it include?

Answer 19

A theory on how enzymes work.

The enzymes changes it shape slightly to force the substrate together or apart.

Question 20

Name some similarities between the two theories. (At least 3)

Answer 20

• Theories on how enzymes work
• Both involve a substrate
• Both involve an active site
• Both speed up reactions

Question 21

What is activation energy?

Answer 21

The amount of energy required for a reaction to occur.

Question 22

How do enzymes speed up the rate of reaction?

Answer 22

The lower the amount of activation energy required for the reaction to take place.

Question 23

What do catalyses do?

Answer 23

They speed up reactions by influencing the stability of bonds in the reactants.

Question 24

Give an example of a catabolic reaction

Answer 24

• Digestion

- Cellular respiration

Question 25

Give an example of a anabolic reaction.

Answer 25

Protein synthesis

Question 26

Do enzymes have more than one use?

Answer 26

Yes! The enzyme can be re-used many times. But eventually will wear out and be replaced.

Question 27

If a lipid enzyme is called Lipases.
And a protein enzyme is called proteases.
What are these called? Sucrose, Lactose, Urea

Answer 27

Sucrose= Sucroses

Lactose= Lactases

Urea= Ureases

Question 28

Many enzymes are ——— in membranes. (Fill in the blank)

Answer 28

1- Embedded

Question 29

The —– the surface are of a ——-, the more ——– can be embedded

Answer 29

1- Greater
2- Membrane
3- Enzymes

Question 30

—— enzymes are often located in particular ——. Even within — regions of the ———. (Fill in the blanks)

Answer 30

1- Specific
2- organelles
3- particular
4- organelle

Question 31

What are the factors that affect enzymes functions?

Answer 31

• Temperature

- pH levels

Question 32

Why does Temp and pH affect the functions of the enzyme?

Answer 32

Because they change how to active site works, so the enzyme can no longer function.

Question 33

How does temperature affect the enzyme?

Answer 33

The warmer the temperature, the faster molecules move. This increases the chance of them colliding and reacting.

Question 34

Enzymes have an ——– Temp/ pH. (Fill in the blank)

Answer 34

1- optimum

Question 35

What happens when the enzyme passes its optimum working conditions?

Answer 35

The enzyme can no longer work in those conditions, it becomes denatured.

Question 36

What does it mean for an enzyme to become denatured?

Answer 36

The enzymes shape, therefore changing the active site so it can no longer bond with the substrate. These changes are irreversible.

Question 37

What is a limiting factor?

Answer 37

Any factor that directly affects the rate of reaction that will occur.

Question 38

Give three examples of a limiting factor.

Answer 38

• Temperature
• pH
• Substrate concentration
• Enzyme concentration
• Reactant products and co-enzymes

Question 39

What is a co-enzymes job?

Answer 39

• To bind to enzymes that can’t bind to a substrate on their own.

Question 40

What are the two types of inhibitors?

Answer 40

1- Competitive inhibitor

2- Non-competitive inhibitor

Question 41

What do competitive inhibitors do?

Answer 41

They fit into the active site instead of the substrate. They are called competitive because they compete for the active site.

Question 42

What do non-competitive inhibitors do?

Answer 42

They do not interfere with the active site. But they attach to the enzyme and change its shape, effecting its ability to work.