Human Nutrition and Biological molecules Flashcards Preview

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Flashcards in Human Nutrition and Biological molecules Deck (36):
1

Mouth function (2 points)

Salivary glands produce amylase enzyme in the saliva
Teeth break down food

2

Oesophagus function

Connects mouth and stomach

3

Liver function

Produces bile

4

Gall Bladder function

Stores bile

5

Large intestine function

Absorbs excess water from food

6

Anus function

Releases faeces

7

Stomach function (2 points)

Breaks food up
Produces pepsin (protease enzyme)

8

Ingestion

Food or drink enters mouth

9

Digestion

Break down of large, insoluble molecules to small, soluble molecules

10

Example of mechanical digestion

Chewing

11

Example of chemical digestion

Digestive enzymes

12

Absorption

Moving molecules through intestine walls to blood

13

Assimilation

Digested molecules move into body cells and become part of the cells

14

Egestion

Undigested material form faeces

15

Pancreas function

Produces protease, amylase and lipase enzymes

16

Small intestine function

Produces protease, amylase and lipase enzymes to complete digestion

17

Describe process of Peristalsis

Muscular tissue that goes down to down to alimentary canal is used to squeeze balls of food, boluses, through gut. This squeezing action ,makes the circular muscles contract, is called peristalsis.

18

Why can starch, protein and fat not pass through walls of digestive system?

Too big and insoluble

19

What do digestive enzymes do

Break down big molecules into smaller ones

20

What does amylase do?

Converts starch into maltose

21

What does maltase do?

Converts maltose into glucose

22

What does protease do?

Converts proteins into amino acids

23

What does lipases do?

Converts lipids into glycerol and fatty acids

24

2 functions of bile

Neutralises stomach acids
Emulsifies fat (breaks into tiny droplets)

25

Where is bile produced?

Liver

26

Where is bile stored?

Gall bladder

27

Where is bile released to?

Small intestine

28

Describe and explain how and why bile neutralises stomach acids

HCl in stomach makes pH for enzymes in small intestine too acidic to work. Bile is alkaline - it neutralises acid and makes pH alkaline as enzymes work best in alkaline conditions

29

Explain how bile makes digestion faster

Bile breaks fat into tiny droplets. This makes bigger surface area for lipase, increasing the rate of digestion

30

3 ways villi are adapted for absorption

Millions of them - more absorption
Single permeable layer of surface cells and good blood supply to assist absorption
Each cell on villus has its own microvilli, to increase surface area for absorption

31

What are carbohydrates made up of?

Glucose and maltose, ect, joined together

32

What are proteins made up of?

Chains of amino acids

33

What are lipids made up of?

Fatty acids and glycerol

34

Describe how to test for glucose

Add benedicts reagent to sample and heat
Make sure doesn't boil
If glucose present, sample goes from blue to brick red

35

Describe how to test for starch

Add iodine solution to sample
If starch present, sample goes from browny-orange to black

36

How does temp effect enzyme reactions

Initially, higher temp increases rate
If it gets too hot, bonds holding enzymes together will break - enzymes lose shape
Active site does not fit this shape
So enzymes denature and reaction stops