2 Organisation - Digestive System Flashcards Preview

AQA Biology Paper 1 11-2B > 2 Organisation - Digestive System > Flashcards

Flashcards in 2 Organisation - Digestive System Deck (69)
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1
Q

Define ‘tissue’.

A

A group of cells with similar structure working together for a specific function

2
Q

Define ‘organ’.

A

A group of tissues working together for specific functions

3
Q

Reorder the following in increasing size order: Organ, cell, tissue, organ system, organism

A

Cell < Tissue < Organ < Organ system < Organism

4
Q

State the function of the salivary glands.

A

Produce digestive enzymes (eg. Amylase)

5
Q

Name the tube that carries food from the mouth to the stomach.

A

Oesophagus/Gullet

6
Q

State the function of the stomach.

A

Releases digestive enzymes to digest food

7
Q

State the function of the liver in the digestive system.

A

Produces bile for lipid digestion

8
Q

State the function of the small intestine.

A

Digest food and absorb nutrients from digested food

9
Q

State the function of the large intestine.

A

Absorb water from digested food

10
Q

State the the function of the pancreas.

A

Produces/Releases digestive enzymes

11
Q

State the function of the gall bladder.

A

Store bile before release into small intestine

12
Q

What are carbohydrates made up of?

A

Simple sugars

13
Q

State the chemical formula of glucose.

A

C6H12O6

14
Q

Name a complex carbohydrate that is made up of glucose.

A

Starch/Cellulose/Glycogen

15
Q

State the importance of having carbohydrates in our diet.

A

Energy source - Break down glucose in respiration to release energy for metabolic reactions

16
Q

What elements make up carbohydrates?

A

C, H, O

17
Q

What are lipids made up of?

A

1 glycerol + 3 fatty acids

18
Q

State the importance of having lipids in our diet.

A

Energy store/Make up cell membranes/Steroid hormones

19
Q

What elements make up lipids?

A

C, H, O

20
Q

What are proteins made up of?

A

Amino acids

21
Q

State the importance of having proteins in our diet.

A

Structural components/Hormones/Antibodies/Enzymes

22
Q

What elements make up proteins?

A

C, H, O, N

23
Q

Name the reagent used to test for starch.

A

Iodine

24
Q

What is a positive result for starch test?

A

Starch turns iodine from brown-red to blue-black

25
Q

Name the reagent used to test for sugars.

A

Benedict’s solution

26
Q

What is the positive result for sugars?

A

Benedict’s solution turn from clear blue to brick-red (precipitate)

27
Q

What is the reagent used to test for proteins?

A

Biuret solution

28
Q

What is the positive result for proteins?

A

Biuret turns from blue to purple

29
Q

What is the reagent used to test for lipids?

A

Ethanol (+water)

30
Q

What is the positive test for lipids?

A

White milky layer

31
Q

State a hazard in doing food tests.

A

Ethanol is flammable/Biuret is corrosive

32
Q

Define ‘catalyst’.

A

A substance that speeds up chemical reactions but don’t get used up

33
Q

Define ‘enzyme’.

A

Biological catalysts that speed up chemical reactions

34
Q

What kind of molecule are enzymes - carbohdyrates, lipids or proteins?

A

Proteins

35
Q

Define ‘active site’.

A

The site on an enzyme where the substrate binds

36
Q

Any substance can fit into the active site of an enzyme. True or false?

A

FALSE

37
Q

Briefly describe the lock- and-key model.

A

Substrate fits into the active site to form enzyme-substrate complex –> Reaction occurs –> Enzyme releases products and binds to another substrate

38
Q

Define ‘metabolism’.

A

Sum of all reactions in a cell/body

39
Q

Define ‘denaturation’.

A

Loss of active site

40
Q

How does temperature affect enzymes’ rate of reaction?

A

As temp increases, RoR increases until after optimum

41
Q

Why do enzymes stop working past their optimum temperature?

A

Denatured (substrate can no longer bind to active site)

42
Q

Why do enzymes not work well at lower temperatures?

A

Inactive (not enough KE to collide and bind to active site)

43
Q

How does a change in pH affect enzyme structure?

A

pH change affects forces holding enzyme structure together, causing it to denature

44
Q

Define ‘ digestion’.

A

Breakdown of large insoluble molecules into smaller soluble substances

45
Q

Name the type of enzyme that digests carbohydrates.

A

Carbohydrases

46
Q

Name the enzyme that digests starch.

A

Amylase

47
Q

Name the product of the breakdown of starch.

A

Simple sugars

48
Q

Name the type of enzyme that digests proteins.

A

Proteases

49
Q

Name the protease that works well in the stomach.

A

Pepsin

50
Q

Name the product of the breakdown of proteins.

A

Amino acids

51
Q

Name the type of enzyme that digests lipids.

A

Lipases

52
Q

Name the products of the breakdown of lipids.

A

Glycerol and fatty acids

53
Q

Which organs produce amylase?

A

Salivary glands and pancreas

54
Q

Which organs produce proteases?

A

Stomach, pancreas, small intestine

55
Q

Which organs produce lipases?

A

Pancreas and small intestine

56
Q

Where does starch digestion occur?

A

Mouth + Small intestine

57
Q

Where does protein digestion occur?

A

Stomach + Small intestine

58
Q

Where does lipid digestion occur?

A

Small intestine

59
Q

How are the nutrients carried away from the gut?

A

Absorbed into bloodstream through small intestine

60
Q

State an observation to determine when the amylase has completed its digestion of starch.

A

Iodine remains brown-red rather than turning blue-black

61
Q

State a reason for setting the amylase solution, starch solution and the buffer in the water bath before the experiment.

A

To ensure all of the same temp, so that temp will not affect the results (fair test)

62
Q

How does the hydrochloric acid in the stomach help with digestion?

A

Provides optimum pH for pepsin to digest proteins

63
Q

Apart from digestion, what is another function of hydrochloric acid in the stomach?

A

Kill pathogens in food

64
Q

How is the stomach adapted to protect itself from the hydrochloric acid?

A

Thick mucus layer/quick renewal of epithelial layer

65
Q

State the two functions of bile.

A

Emulsifies fats + Neutralises food from stomach (HCl)

66
Q

What is emulsification?

A

Physically breaking down large oil drops into smaller droplets, increasing surface area for lipases to work on

67
Q

Bile is an enzyme. True or false?

A

FALSE

68
Q

Hydrochloric acid in the stomach breaks down food. True or false?

A

FALSE - provides optimum pH for pepsin and kills bacteria, NOT digest food

69
Q

State the importance of the neutralising role bile has.

A

Small intestine does not have protective mucus layer + Enzymes will denature in small intestine