Digestion

Question 1

What is digestion?

Answer 1

The process of hydrolysing large, insoluble molecules into small, soluble molecules to be utilised by the body

Question 2

What are the 5 processes of digestion?

Answer 2

Ingestion
Digestion
Absorption
Assimilation
Egestion

Question 2

Why is digestion important?

Answer 2

• Maintaining good health
• Ensuring that the body receives the nutrients it needs in order to function
• Breaks insoluble into soluble molecules

Question 3

What is ingestion?

Answer 3

The process of taking food in through the mouth

Question 4

What is absorption?

Answer 4

The process in which soluble molecules from digested food in taken up by cells in the intestines to the bloodstream

Question 5

What is assimilation?

Answer 5

Absorbed nutrients are used by the body for energy, growth and cell repair

Question 6

What is egestion?

Answer 6

The removal of undigested waste by the body

Question 7

What bonds are hydrolysed in digestion?

Answer 7

Carbohydrates: glycosidic
Lipids: ester
Proteins: peptide

Question 8

What’s the function and adaptations of the mouth?

Answer 8

Function: carbohydrate digestion begins here
Adaptations: contains teeth to break food down

Question 9

What’s the function and adaptations of the oesophagus?

Answer 9

Function: Food passes through from mouth to stomach
Adaptations: contains smooth muscle to push the food down

Question 10

What’s the function and adaptations of the stomach?

Answer 10

Function: protein digestion begins here, enzymes and stomach acid are produced to break food down
Adaptations: stomach acid unravels proteins to enable enzyme activity
Muscular tissue churns food to mix it with enzymes and acid

Question 11

What’s the function and adaptations of the liver and pancreas?

Answer 11

Function: produces bile to digest fats, contains enzymes
Adaptations: Bile salts lowers surface tension and creates a larger surface area

Question 12

What’s the function and adaptations of the small intestine?

Answer 12

Three sections:
- Ileum
- Duodenum
- Jejunum
Carbohydrate, protein and lipid digestion
Soluble food molecules absorbed into bloodstream
Water absorption occurs here
Adaptions: walls contain smooth muscle tissue that rhythmically contract to move food along
Ileum is long and lined with finger-like villi to increase surface area

Question 13

What’s the function and adaptations of the large intestine?

Answer 13

Function: any food that wasn’t digested is stored in the rectum as faeces
Adaptations: large lumen, smaller in length, thinner wall than small intestine which allows for diffusion