The digestive system

Question 1

What is mechanical digestion

Answer 1

• Breakdown of food into smaller particles

- This occurs in the mouth, stomach, and jejenum and ileum (small intestine)

Question 2

Describe the Mouth

Answer 2

• Food is ingested in the mouth

- Food is then chewed by the teeth + jaw and mixed with saliva by the tongue

Question 3

Describe the Teeth

Answer 3

• 4 types of teeth in humans:
• 4x Incisors
• 2x Canines
• 4x Premolars
• 6x Molars

Question 4

Describe Incisors

Answer 4

Chisel shape teeth for cutting and bitting

Question 5

Describe Canines

Answer 5

Cone shaped teeth for tearing

Question 6

Describe Premolars and Molars

Answer 6

Broad crown with rounded cusps for grinding and crushing

Question 7

Describe the Stomach

Answer 7

• HAs 3 Layers of muscle…
  Oblique
  Circular
  Longitudinal
  … In contrast to the rest of the alimentary canal which only has 2 (circular and longitudinal)
• Allows stomach to churn food and mix it with stomach juices

Question 8

Describe the duodenum

Answer 8

• Liver produces bile salts, which are stored in the gall bladder
• Bile is released by the gall bladder into the duodenum and emulsify fats, mechanically breaking food into tiny droplets (increasing the surface area)

Question 9

Describe the Jejenum and ileum?

Answer 9

• Has muscular walls which push along (peristalsis) and divide it into smaller clumps and mix it (segmentation)