3.3.3.1 Proteins - Enzymes and Digestion Flashcards Preview

SHHS - Science - NEW AQA A-Level Biology (Year 1) > 3.3.3.1 Proteins - Enzymes and Digestion > Flashcards

Flashcards in 3.3.3.1 Proteins - Enzymes and Digestion Deck (55):
1

The 2 stages of digestion in humans are...

Physical breakdown by teeth or stomach churning

Chemical digestion by enzymes

2

What is the function of the pancreas?

Releases pancreatic juice onto food, as it exits the stomach, which contains proteases, lipases and carbohydrases.

3

Give some examples of proteases involved in digestion

Endopeptidase

Exopeptidate

Dipeptidase

4

What is the function of teeth?

To physically bread down food and increase its surface area

5

Identify the part of the digestive system

Q image thumb

Oesophagus

A image thumb
6

Identify the part of the digestive system

Q image thumb

Gall Bladder

A image thumb
7

What is meant by chemical digestion?

When large food molecules are hydrolysed into smaller molecules by enzymes.

8

Give some examples of carbohydrases involved in digestion

Salivary Amylase

Pancreatic Amylase

Maltase

Sucrase

Lactase

9

Name the cell membrane-bound protease

Dipeptidase

10

Bile salts are produced by the...

liver

11

What is the function of maltase?

To break down maltose into 2 α-glucose molecules

12

What is the function of the stomach?

Produces proteases for protein digestion

Churns food to physically break it down

13

Identify the part of the digestive system

Q image thumb

Rectum

A image thumb
14

What is the function of salivary amylase?

To hydrolyse starch into maltose

15

What is the function of lipase?

To hydrolyse the ester bonds in triglycerides to give fatty acids and monoglycerides

16

How does the body break down maltose?

The lining of the ileum has maltase enzymes bound to their membranes.

17

Identify the part of the digestive system

Q image thumb

Pancreas

A image thumb
18

What is the function of exopeptidases?

To hydrolyse the peptide bonds at the ends of peptide molecules, which releases amino acids and dipeptides.

19

Name the 3 membrane-bound disaccharidases...

Maltase

Sucrase

Lactase

20

What is the function of dipeptidases?

To hydrolyse the peptide bonds between dipeptides.

They are membrane bound enzymes.

21

What is the function of the ileum (small intestine)?

Produces enzymes to digest food

Absorbs the products of digestion into the blood.

22

What is the function of the oesophagus?

To carry food from the mouth to the stomach

23

What is the function of the large intestine?

To absorb water

24

Identify the part of the digestive system

Q image thumb

Salivary Glands

A image thumb
25

What is meant by egestion?

The removal of faeces via the anus

26

Identify the part of the digestive system

Q image thumb

Ileum (small intestine)

A image thumb
27

Identify the part of the digestive system

Q image thumb

Large Intestine

A image thumb
28

What is the function of bile salts?

To emulsify large lipid molecules into smaller lipid micelles. To increase the surface area that lipase can act on.

29

What is the function of lactase?

To hydrolyse the glycosidic bond in a lactose molecule to give glucose and galactose.

30

What is the function of pancreatic amylase?

To hydrolyse starch in the ileum that was not broken down in the mouth.

31

How does physical breakdown aid digestion?

Creates a larger surface area for enzymes to act on.

Makes food easier to ingest (swallow).

32

Starch is not digested when food enters the stomach. Why?

The salivary amylase enzymes are denatured by the hydrochloric acid in the stomach.

33

What is the function of endopeptidase?

To hydrolyse the central peptide bonds in a large protein molecule to give smaller peptide molecules.

34

Name the 3 categories of enzymes.

Carbohydrases

Proteases

Lipases

35

Which type of bond does amylase break?

α 1-4 glycosidic bonds

36

What is meant by hydrolysis?

When a water molecule is added to a molecule to break a chemical bond.

37

What is the function of sucrase?

To hydrolyse the glycosidic bond in a sucrose molecule to give glucose and fructose.

38

Identify the part of the digestive system

Q image thumb

Anus

A image thumb
39

Which enzyme is produced by the salivary glands?

Salivary Amylase

40

Enzymes are secreted by...

glands

41

What is the function of the rectum?

The final section of the intestines which stores faeces

42

What is a monoglyceride?

A glycerol molecule with 1 fatty acid attached.

43

Name the 3 proteases (peptidases) that are involved in protein digestion.

Endopeptidase

Exopeptidase

Dipeptidase

44

Bile salts emulsify large lipid molecules into smaller lipid molecules called...

micelles

45

What is a membrane-bound disaccharidase?

An enzyme that is part of the epthelial cell surface membranes of the ileum. They break down disaccharides.

46

What is a gland?

An organ in the body that secretes substances such as enzymes or hormones.

47

Identify the part of the digestive system

Q image thumb

Stomach

A image thumb
48

What is the function of the salivary glands?

They secrete the enzyme salivary amylase, which hydrolyses starch into maltose.

49

How is glucose absorbed by co transport in the GUT with Na ions?

1. co transport

2. Na ions actively transported from ileum cell to the blood

3. maintains a diffusion gradient for Na to enter the ileum cell from the gut lumen (bringing glucose with it)

4. glucose enters with Na

5. glucose enter to blood by faciliated diffusion

50

exo and edopeptidases are required for protein hydrolysis - name another enzyme needed to complete protein hydrolysis

dipeptidases

51

what do endopeptidases do?

Endopeptidases hydrolyse internal (peptide bonds)

52

What do exopeptidases do?

Exopeptidases remove amino acids/hydrolyse (bonds) at end(s);

53

Why does the action of exo and endopeptidases result in more efficient hydrolysis?

endopeptidases create more ends or increase in surface area (for exopeptidases);

54

Describe the action of membrane dipeptidases

Hydrolyse peptide bond to release amino acids 

(dipeptides cannot cross the cell membrane)

55

define digestion

HYDROLYSIS of LARGE insoluble molecules into SMALLER soluble molecules