Chapter 8: Enzymes

Question 1

Catalyst

Answer 1

A substance that increase speeed up the rate of a chemical reaction and is not a changed by the reaction

Question 2

Metabolic reactions

Answer 2

Metabolic reactions are all chemical reactions that occur in cells .they include reactions that are catalysed by enzymes

Question 3

Anabolic reactions

Answer 3

Is a reaction that build complex compounds from simple ones for example photosynthesis

Question 4

Catabolic reaction

Answer 4

Is a reaction that break down complex compounds into simple ones example digestion of food

Question 5

Flashcard 1: Enzymes

Answer 5

• Definition: Enzymes are biological catalysts that speed up chemical reactions in living organisms.
• Nature: Enzymes are proteins.
• Specificity: Each enzyme catalyzes a specific reaction.

Question 6

Flashcard 2: Catalyst

Answer 6

• Definition: A substance that speeds up the rate of a chemical reaction without being consumed in the reaction.
• Enzymes act as catalysts in biological systems.

Question 7

Flashcard 3: Substrate

Answer 7

• Definition: The specific reactant that an enzyme acts on.
• Enzymes bind to their substrates at the active site to catalyze the reaction.

Question 8

Flashcard 4: Active Site

Answer 8

• Definition: The region of an enzyme where the substrate binds and the chemical reaction takes place.
• Specificity: The active site has a specific shape that fits the substrate.

Question 9

Flashcard 5: Enzyme-Substrate Complex

Answer 9

• Definition: The temporary complex formed when an enzyme binds to its substrate.
• The enzyme converts the substrate into the product(s) of the reaction.

Question 10

Flashcard 6: Lock and Key Model

Answer 10

• Definition: A model for enzyme-substrate interaction where the active site of the enzyme has a specific shape that fits the substrate like a key fits a lock.

Question 11

Flashcard 7: Induced Fit Model

Answer 11

• Definition: A model for enzyme-substrate interaction where the active site of the enzyme changes shape slightly to accommodate the substrate.

Question 12

Flashcard 8: Factors Affecting Enzyme Activity

Answer 12

1. Temperature
2. pH
3. Substrate Concentration
4. Enzyme Concentration
5. Presence of Inhibitors

Question 13

Flashcard 9: Optimum Conditions for Enzyme Activity

Answer 13

• Temperature: Each enzyme has an optimal temperature at which it works best.
• pH: Each enzyme has an optimal pH at which it works best.

Question 14

Flashcard 10: Denaturation

Answer 14

• Definition: The change in the shape of an enzyme due to extreme conditions, such as high temperature or extreme pH.
• Denatured enzymes lose their activity because their active site changes shape.

Question 15

Flashcard 11: Enzyme Inhibitors

Answer 15

• Definition: Molecules that bind to enzymes and decrease their activity.
• Types: Competitive inhibitors and non-competitive inhibitors.

Question 16

Flashcard 12: Competitive Inhibitors

Answer 16

• Definition: Inhibitors that bind to the active site of an enzyme, competing with the substrate.
• Effect: They reduce the activity of the enzyme by preventing the substrate from binding.

Question 17

Flashcard 13: Non-Competitive Inhibitors

Answer 17

• Definition: Inhibitors that bind to an allosteric site on the enzyme, not competing with the substrate.
• Effect: They change the shape of the enzyme, reducing its activity.

Question 18

Flashcard 14: Enzyme-Substrate Concentration Graph

Answer 18

• Shape: Initially, the rate of reaction increases with substrate concentration until all enzymes are occupied (saturation point).

Question 19

Flashcard 15: Enzyme Denaturation Graph

Answer 19

• Shape: Shows a decrease in enzyme activity with increasing temperature, peaking at the optimum temperature, and then decreasing rapidly due to denaturation.

Question 20

Flashcard 23:
What is an enzyme

Answer 20

• Term: Enzyme
• Definition:A biological catalyst that speeds up chemical reactions in living organisms.

Question 21

• Term:Metabolic reactions

Answer 21

• Definition:Chemical reactions that occur within cells of an organism to maintain life. These reactions are responsible for energy production, synthesis of molecules, and breaking down of molecules.

Question 22

• Term:Characteristics of enzymes

Answer 22

• Details:
  
  • Specificity: Each enzyme works on a specific substrate.
  • Efficiency: Speed up reactions without being used up.
  • pH and temperature sensitivity: Work best within a specific pH and temperature range.
  • Denaturation: Lose their shape and function when exposed to extreme conditions.

Question 23

• Term: Substrate

Answer 23

• Definition: The molecule or substance the enzyme acts on.

Question 24

Term:** Active site

Answer 24

• Definition: The ‘dent’ on the enzyme which is exactly the correct shape for the substrate to fit into.

Question 25

- **Term:** Enzyme-substrate complex

Answer 25

- **Definition:** The substrate bonds with the enzyme’s active site and an enzyme-substrate complex is formed.

Question 26

- **Term:** Products

Answer 26

- **Definition:** ‘New’ molecules that leave the active site after the enzyme acts on the substrate. ---

Question 27

- **Term:** Amylase

Answer 27

- **Substrate:** Starch - **Product:** Maltose ---

Question 28

- **Term:** Maltase

Answer 28

- **Substrate:** Maltose - **Product:** Glucose ---

Question 29

- **Term:** Lipase

Answer 29

- **Substrate:** Lipids (fats & oils) - **Product:** Fatty acids & glycerol ---

Question 30

- **Term:** Sucrase

Answer 30

- **Substrate:** Sucrose - **Product:** Fructose & glucose ---

Question 31

- **Term:** Pepsin

Answer 31

- **Substrate:** Proteins - **Product:** Polypeptides ---

Question 32

- **Term:** Trypsin

Answer 32

- **Substrate:** Polypeptides - **Product:** Amino acids ---

Question 33

- **Term:** Optimum temperature

Answer 33

- **Definition:** The temperature at which the rate of reaction is greatest for an enzyme. ---

Question 34

- **Term:** Low temperature effect on enzyme activity -

Answer 34

**Details:** Rate of enzyme activity is slow, less kinetic energy, fewer collisions between enzymes and substrates, fewer ESCs formed. -

Question 35

**Term:** High temperature effect on enzyme activity

Answer 35

**Details:** More kinetic energy, enzyme vibrates too much, breaks bonds, active site changes shape, substrate won't fit, enzyme denatures. --- - *

Question 36

*Term:** Optimum pH - *

Answer 36

*Definition:** The pH where the rate of enzyme activity is the fastest. - *

Question 37

*Term:** Amylase activity pH

Answer 37

Details:** Works best in neutral conditions like pH 7-7.5, as in saliva.

Question 38

- Term:** Pepsin activity pH

Answer 38

Details:** Works best in acidic conditions like in the stomach. ---

Question 39

- **Term:** Lipase activity pH - **

Answer 39

Details:** Works best in alkaline conditions like in the duodenum. - **

Question 40

Term:** Seed germination and enzymes

Answer 40

- **Details:** Seeds contain inactive enzymes and insoluble nutrients. Enzymes become activated when the seed absorbs water. Enzyme amylase changes starch into maltose, protease digests proteins, and lipase digests lipids. ---

Question 41

- **Term:** Biological washing powders and enzymes - **

Answer 41

Details:** Contain enzymes which breakdown insoluble proteins, fats, and starch stains. Resulting smaller molecules are soluble and can be washed away easily. ---

Question 42

**Term:** Enzymes in the food industry - **

Answer 42

Details:** Rennin or chymosin in cheese making, pectinase in fruit juice production, amylase in bread baking, trypsin in baby food, and papain in tenderizing meat. --- **

Question 43

- **Term:** Biological powder investigation requirements

Answer 43

- **Details:** Two boiled eggs, two teaspoons, two glass beakers with water, regular and biological detergent. ---

Question 44

- Term:Biological washing powder test procedure

Answer 44

- Details:Boil eggs, mark spoons, collect yolk on spoons, dissolve washing powders, observe yolk digestion.