Enzymes

Question 1

What are enzymes?

Answer 1

All Enzymes are proteins. Enzymes are biological catalysts, which speed up the rate of reactions, without being used up in the process.

Question 2

What does carbohydrase break down?

Answer 2

complex carbs into simple sugars

Question 3

What does protease break down?

Answer 3

proteins into amino acids

Question 4

What does lipase break down ?

Answer 4

fats into fatty acids and glycerol

Question 5

Are enzymes substrate specific?

Answer 5

yes

Question 6

What will effect the rate of an enzyme reaction?

Answer 6

Concentration of enzymes and substrates, the pH, the temperature

Question 7

what term is used to describe the best temperature or pH for a reaction?

Answer 7

Optimum pH/temperature

Question 8

What will cause denaturation ?

Answer 8

Very high temperatures or extremes of pH

Question 9

Is denaturation irreversible?

Answer 9

Yes, the substrate will no longer fit into the active site

Question 10

What is enzymes optimum temperature?

Answer 10

body temperature (37.5 degrees Celsius)

Question 11

What pH do protease and amylase work best at?

Answer 11

protease - slightly acidic

amylase - slightly alkaline

Question 12

Does extreme cold temperatures denature enzymes ?

Answer 12

No, it will slow down the reaction but not denature the enzyme.

Question 13

What happens when the temperature of enzymes is reduced?

Answer 13

1 - Less kinetic energy
2 - particles move around less and are less likely to collide with one another
3 - slows the rate of the reaction

Question 14

What happens when the temperature of the particles is increased?

Answer 14

1 - increased kinetic energy
2 - particles move around faster
3 - the increased chance for a reaction to occur
4 - increasing it to its optimum temp will make the reaction happen at its max rate.

Question 15

What happens when you increase the concentration of enzymes?

Answer 15

1 - more likely a substrate will collide with an enzyme and be broken down into products
2 - increases the rate of the reaction

Question 16

What are enzyme inhibitors?

Answer 16

They are molecules that fit loosely into the active site, preventing the substrate entering. This leads to reduced rate of reaction

Question 17

What are enzymes 5 most important properties?

Answer 17

1 - they're all proteins
2 - they are specific
3 - they can be used again and again 
4 - they are affected by temperature
5 - they are affected by pH

Question 18

Give three examples of commercial enzyme uses .

Answer 18

biological washing powder, baby food, making lactose free milk, production of syrup, extracting juice from fruit

Question 19

What is the definition of digestion?

Answer 19

Digestion is the breakdown of large insoluble complex food molecules into smaller simple soluble molecules which enter the blood stream for distribution around the body.

Question 20

Why do we digest food?

Answer 20

Because when we eat food the food molecules are too big for our body to use. So we break them down into smaller soluble pieces that we can use.

Question 21

approx. how long is the digestive system?

Answer 21

7 meters long

Question 22

What are the two types of digestion?

Answer 22

Mechanically and chemically

Question 23

What are the end products of digestion ?

Answer 23

simple sugars, amino acids, fatty acids and glycerol. they are small and soluble

Question 24

What are the main features of the Ileum? ( small intestine )

Answer 24

It's very long
It has a folded surface to increase surface area
Has villi, which have micro-villi
Has a good blood supply
contains thin and permeable membranes

Question 25

What is insude the villi ?

Answer 25

A lacteal which leads to the lymphatic system.

Question 26

Where is the food absorbed by the lacteal transported to ?

Answer 26

The liver

Question 27

How does the liver used the food absorbed by the lacteal?

Answer 27

Sugars - used in respiration
Excess sugar - converted into glycogen ( stored in liver)
Excess carbs - converted into fat ( stored in liver+skin)
Amino acids - make proteins (for cell growth and repair)