Digestion and Absorption

Question 1

What is hydrolysis?

Answer 1

Breaking bonds by adding water

Question 2

What is digestion

Answer 2

Physical breakdown

Question 3

Physical breakdown

Answer 3

-Breakdown of food into absorbable nutrients

Question 4

Chemical digestion

Answer 4

Hydrolyses large, insoluble molecules

Question 5

What is the importance of digestion?

Answer 5

Hydrolyses large food molecules into smaller molecules

Question 6

Oesphagus

Answer 6

carries food from mouth to stomach. adapted for transport. made up of a thick muscular wall

Question 7

stomach

Answer 7

muscular sac between the oesphagus and the small intestine where digestion of food begins

Question 8

ileum

Answer 8

Part of small intestine

Question 9

large intestine

Answer 9

Absorbs water and forms feces

Question 10

Rectum

Answer 10

stores feces

Question 11

Salivary glands

Answer 11

Contain amylase to hyrdolyse starch into maltose

Question 12

Pancreas

Answer 12

Pancreatic juice (hydrolyse proteins, lipids and starch)

Question 13

Why are different enzymes needed to catalyse the breakdown of carbohydrates, proteins and lipids?

Answer 13

Enzymes are proteins with specific tertiary structures

Question 14

Where is amylase produced?

Answer 14

Pancreas, salivary glands and small intestine

Question 15

Where is amylase secreted?

Answer 15

Mouth and small intestine

Question 16

What is amylase for

Answer 16

Hyrdolyses alternate glycosidic bonds of starch molecule to produce maltose

Question 17

Where is maltase produced?

Answer 17

(In the cell membrane of epithelial cells)

Question 18

Maltose

Answer 18

glucose + glucose

Question 19

Where is maltase secreted?

Answer 19

Small intestine

Question 20

Role of maltase

Answer 20

Hyrdolyses maltase into monosaccharide (alpha glucose)

Question 21

Process of carbohydrate digestion

Answer 21

• Saliva breaks down and hydrolyses food to maltose (neutralises pH)

Question 22

Process of carbohydrate digestion (muscles in intestine)

Answer 22

Muscles in intestine wall push food along ileum

Question 23

Sucrase

Answer 23

hydrolyses sucrose into glucose and fructose

Question 24

Lactase

Answer 24

an enzyme that catalyzes the hydrolysis of lactose to glucose and galactose.

Question 25

What are the roles of the glands in the digestive system?

Answer 25

To produce digestive juices

Question 26

Name two types of glands in the digestive system

Answer 26

Pancreatic glands

Question 27

What is the function of the small intestine in the digestive system?

Answer 27

It is where some digestion occurs and the absorption of soluble food also occurs

Question 28

What is the function of the stomach in the digestive system?

Answer 28

It is where digestion occurs.

Question 29

What is the role of the liver in the digestive system?

Answer 29

It produces bile

Question 30

What are enzymes?

Answer 30

Biological catalysts with a specific shape active site

Question 31

Where is lipase produced?

Answer 31

Pancreas and small intestine

Question 32

Where is lipase secreted?

Answer 32

The small intestine

Question 33

Role of lipase

Answer 33

digests lipid molecules; necessary for the preparation of absorption of triglycerides

Question 34

emulsification

Answer 34

Breakdown of large fat globules into smaller, digestible particles (micelles)

Question 35

Where is protease produced?

Answer 35

Stomach, pancreas and small intestine

Question 36

Where is protease secreted?

Answer 36

Stomach and small intestine

Question 37

Different peptidases

Answer 37

Endopeptidases

Question 38

Endopeptidase

Answer 38

Hydrolyse peptide bonds between amino acids in central region of protein molecule

Question 39

Exopeptidase

Answer 39

Hydrolyses peptide bonds on end of peptide molecules (formed from endopeptidases)

Question 40

Dipeptidase

Answer 40

splits dipeptides into amino acids

Question 41

What is the role of bile in the digestive system?

Answer 41

Neutralises HCl (from stomach) to provide alkaline conditions in which small intestine enzymes work best

Question 42

Where is bile produced?

Answer 42

Liver

Question 43

Where is bile stored?

Answer 43

Gall bladder

Question 44

What are proteins hydrolysed to?

Answer 44

Amino acids

Question 45

What is starch hydrolysed to?

Answer 45

alpha glucose

Question 46

What is fat hydrolysed to?

Answer 46

Fatty acids and glycerol

Question 47

Why can starch not be absorbed as easily?

Answer 47

It is a large, insoluble molecule

Question 48

What is starch first digested to?

Answer 48

Maltose

Question 49

What is maltose digested to?

Answer 49

alpha glucose

Question 50

Explain how starch is hydrolysed to maltose

Answer 50

Amylase in the small intestine and mouth hydrolyses the glycosidic bonds

Question 51

Explain how maltose is hydrolysed to alpha glucose

Answer 51

Maltase (membrane bound disaccharidase)

Question 52

Which monosaccharides is sucrose hydrolysed to?

Answer 52

Glucose

Question 53

Which monosaccharides is lactose hydrolysed to?

Answer 53

Glucose

Question 54

How is the small intestine adapted for digestion?

Answer 54

The lining Is folded into villi which give a large surface area

Question 55

Explain how dipeptides are hydrolysed to amino acids

Answer 55

Dipeptidases in the cell surface membrane of epithelial cells

Question 56

Explain the steps in the digestion of a protein to a dipeptide

Answer 56

Endopeptidases hydrolyse peptide bonds within the protein

Question 57

Explain how amino acids are absorbed

Answer 57

Na+ actively transported into the ileum from the epithelial cells

Question 58

Where does lipid digestion occur?

Answer 58

The lumen of the small intestine

Question 59

Explain the role of bile in lipid digestion

Answer 59

Bile salts emulsify lipids

Question 60

Explain lipid digestion

Answer 60

In the small intestine lipase hydrolyses ester bonds

Question 61

Explain how the products of lipid digestion are absorbed

Answer 61

Micelles move monoglycerides and fatty acids to the epithelium

Question 62

Explain why chylomicrons leave the cell by exocytosis

Answer 62

They are too large to leave by any other method

Question 63

Give an advantage of maltose being in the cell membrane and not secreted in pancreatic juice

Answer 63

It's a more effective way to absorb the products

Question 64

Why would damage to the microvilli cause the amino acid concentration of the blood to decrease?

Answer 64

Decreases surface area of epithelial cells

Question 65

Explain co transport of glucose and sodium ions

Answer 65

Na+ actively transported out of epithelial cells into blood

Question 66

What is the difference in the co-transport of amino acids and the co-transport of glucose?

Answer 66

With glucose - Na+ are actively transported into the blood

Question 67

How is the ileum adapted for absorption?

Answer 67

- Thin walls lined with epithelial cells on other side which is rich with capillaries, which can carry absorbed molecules away

Question 68

Absorption of amino acids and monosaccharides

Answer 68

Diffusion and co-transport

Question 69

Absorption of triglycerides

Answer 69

Micelles break down when in contact with epithelia cells, releasing monoglycerides and fatty acids (non- polar so diffuse)