B3- Organisation And The Digestive System Flashcards Preview

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Flashcards in B3- Organisation And The Digestive System Deck (95)
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1

What is a tissue

A group of cells with similar structure and function working together

2

What is an organ

Collection of tissues

3

What does each organ contain?

Several tissues, all working together to perform a specific function

4

What tissues do the stomach contain and what are their functions

muscular tissue- churn food + digestive juices of stomach together

glandular tissue-produces digestive juices that break down food

Epithelial tissue- covers the inside + outside of stomach

5

What two important functions do the pancreas has

Makes hormones to control blood sugars + enzymes that digest food

Contains two very dif. Types of tissue

6

What is an organ system

groups of organs that all work together to perform specific functions

7

What is the function of the liver?

Producing bile

8

Give me 4 examples of organ system

Circulatory
Digestive
Nervous
Excretory

9

What does carbohydrates break down into and by what enzyme?

Sugars
Carbohydrase

10

What are proteins broken down into and what enzyme?

Protease
Amino acids

11

What are fats broken into and what enzyme?

Lipase
Fatty acids and glycerol

12

What is ingestion?

Taking in of food w/ help of mouth
Happens w/ help of mouth
Teeth + tongue helps churning of food + mix of saliva

13

What is digestion

Breakdown of large insoluble particle into small soluble ones

Happens w/ help of stomach, intestine, pancreas and liver

14

What is absorption?

Digested food particles are absorbed into the blood

Small intestine

15

What is assimilation?

Using absorbed food for releasing energy and in body processes

In the body cells

16

Egestion

Getting rid of undigested food materials

By rectum and anus

17

What is Bile juice?

Green yellow ALKALINE liquid which is PRODUCED in the LIVER and STORED in the GALL BLADDER

18

What are two of bile juices major functions?

Neutralisation

Emulsification of fats

19

What is neutralisation in the body

food that comes out of stomach is acidic

enzymes of intestine can work in alkaline conditions

Bile neutralises food that come from stomach-makes it alkaline so enzyme released in the intestine can work effectively

20

What is the emulsifications of fat?

For lipase to work-> fat broken down into small droplets to increase surface area for the lipase to function

Bile performs this for efficient working lipase

21

What is the function of carbohydrates?

Principle source of energy

Fuel for respiration

Storage molecules

Structure molecules

22

What is an example of storage molecules

Starch and glycogen

23

What is an example of a structure molecule

Cellulose

24

What is the 3 functions for protein

Components of muscles

Required for growth and repair

Components of enzymes

Hormones like insulin

25

What are the 3 functions of fats

Insulates the body

Reserve source of energy

Components of cell membrane

26

What are all carbohydrates made up of?

Units of sugar

27

What elements do carbohydrates contain?

Carbon, hydrogen and oxygen

28

What is a simple sugar?

Small carbohydrate containing only one sugar unit

29

What is the best known single sugar?
What is the chemical formula

Glucose C6H12O6

30

What are complex carbohydrates? Give an example

Long chains of simple sugar units bonded together

Starch

Cellulose

31

What are lipids

Fats (solids) and oils (liquid)

32

Combined w other molecules, lipids are important where?

Cell membranes as hormones, and in nervous system

33

Truth or false: lipids are insoluble in water

True

34

What are lipids made up of?

Carbon, hydrogen and oxygen

35

What are lipids made up of?

three molecules of fatty acids joined to a molecule of glycerol

36

In lipids, glycerol is always the ______ but the fatty acids _______

same


Vary

37

What do lipid-rich food include?

all oil

butter, margarine, cheese, and cream

38

What does the different combination of fatty acids affect?

Whether the lipid will be a liquid oil or a solid fat

39

What are proteins used for?

building up the cells and tissues of the body


Basis of all enzymes

40

How much of your body mass is protein?

Between 15 and 16 percent

41

Where is protein found?

In tissues, ranging from your hair and nails to the muscles that move you around

In enzymes that control your body chemistry

42

What are proteins made up of?

Carbon hydrogen oxygen and nitrogen

43

Protein rich food include...

Meat fish pulses and cheese

44

What is a protein molecule made up of?

Long chains of small units called amino acids

45

There are __ different _____ _____, and they are _____ together into _____ _____ by ______ _____

i)20
ii)amino acids
iii)joined
iv)long chains
v)special bonds

46

What shape are the long chains of amino acids that make up a protein

Folded, coiled, and twisted go make specific 3D shapes

47

What enables molecules to fit into a protein

The 3D specific shapes from the folded, coiled and twisted amino acids

48

The bonds that hold the proteins in these 3D shapes have what features?

v sensitive to temp and pH

Can be easily broken

49

What happens when the bonds that hold the proteins in these 3D shapes is broken?

Shape of protein is lost
May not function any more in your cells

50

What is the term that describes when the shape of protein is lost?

The protein is denatured

51

What 4 functions for proteins carry out?

Structural components of tissues (muscles and tendons)

Hormones (insulin)

Antibodies (destroy pathogens part of immune system)

Enzymes (catalyst)

52

In your body, what is the rate of chemical reactions controlled by?

Enzymes

53

What are enzymes?

Special biological catalysts that speed up reactions

54

What do enzymes do?

Each enzyme interacts w a particular substrate (reactant)

55

Enzymes are large _____ _________

Protein molecules

56

Why are the long chains of amino acids folded?

To produce a molecule with an active site that has a unique shape so it can bind to a specific substrate molecule

57

The ____ of an enzyme is vital for the enzyme to ______

i) shape
ii)function

58

What theory is a simple model of how enzyme works?

Lock and key theory

59

What does lock and key theory involve?

Substrate of reaction to be catalysed -fits into the active site of the enzyme

enzyme and the substrate bind together

60

What happens after the enzyme and substrate bind together?

Reaction takes place rapidly

The products are released from the surface of the enzyme.

61

What is another feature enzymes can do other than break up large molecules?

Enzymes can join small molecules together

62

TRUE OR FALSE Enzyms do change the reaction

False- they speed it up

63

What do enzymes control

Metabolism

64

Give me 3 ways in which different enzymes catalyse specific types of metabolic reactions

1) Building large molecules from lots of small ones

2)Changing one molecule into another

3) Breaking down large molecules into smaller ones

65

What does building large molecules from lots of smaller ones include?

Building starch, glycogen or cellulose from glucose

Lipids from fatty acids

Proteins from amino acids

Plant cells- combine co2 w h2o to make glucose- uses glucose + nitrate ions to make amino acids

66

What does changing one molecule into another include?

Changing one simple sugar into another

Such as glucose to fructose

And converting one amino acid into another

67

What does breaking down large molecules into smaller molecules include?

Breaking down carbs, lipids + proteins into their constituent molecules during digestion

Breaking down glucose in cellular respiration

Breaking down excess amino acids to form urea, and other molecules used in respiration

68

Do reactions that take place in the cell happen at relatively low or high temps?

Relatively low

69

What temperature are most organisms are able to withstand?

40 degrees celsius

70

What is affected after an organism reaches 40°C ?

Protein structure of the enzyme is affected by the high temp.

71

What happens to the long amino acid chains when an enzyme is said to be denatured?

Begin to unravel, and as a result, the shape of the active site changes. Substrate cannot fit active site and no longer acts as a catalyst

72

In which temp do most human enzymes work best?

37°C

73

Where does the shape if the active site if an enzyme come from?

Forces between dif. parts of the protein molecule

74

What do the forces between the different parts of the protein molecule do?

Holds the folded chains in place

75

What affects these forces between the different parts of the protein molecule?

A change in pH, changes shape of molecules

76

Most of your enzymes work where? Doing what?

Inside of cells; controlling the rate of chemical reactions

77

Where do the digestive enzymes work?

Outside of the cells

78

Where are enzymes produced?

By specialised cells in glands (pancreas) and in the lining of the digestive system

79

What happens to the enzymes after they are produced?

The enzymes pass put of these cells into the digestive system itself, where they come into contact w/ food molecules

80

What is your digestive system?

A hollow, MUSCULAR tube that squeezes your food that helps to break up your food into small pieces that have a large surface area for enzymes to work on

81

What enzyme catalyses the broken down of starch?

Amylase

82

Where is starch broken down to sugars?

Mouth

Small intestine

83

Where is amylase produced?

Salivary glands and pancreas

84

Where does the digestion of starch start?

In mouth

85

What catalyzes the break down of protein such as meat, fish and cheese into amino acids?

protease enzymes

86

Where is protease produced?

the stomach, pancreas and small intestine

87

Where does the breakdown of proteins into amino acids take place?

stomach and small intestine

88

Where is the lipase made?

pancreas and small intestine

89

What happens to the food molecules after theyhave been completely digested into soluble glucose, amino acids, fatty acids and glycerol?

They leave your small intenstine and then pass into the bloodstream to be carried around to body to the cells that need them

90

What do all the 35 millions glands in the lining of your stomach secrete?

Pepsin- protease enzyme- digests protein you eat

91

Which pH does pepsin work best at?

acidic

92

How much litres of hydochloric acid does your stomach produce a day?

30

93

why is it useful to have highly concentrated
hydrochloric acid in your stomach

Allows enzymes to work effectiviely
Kills most of the bacteria you take in w/ your food

94

The stomach produces a thick layer of mucus. What is it's function?

coats stomach walls
protects them from being digested by the acid and enzymes

95

What happens if someone has a stomach ulcer?

Protecting mucus is lost
acid production may decrease
Lining of stomach is then attacked by the acid and protein-digesting enzymes- painful