digestive ststem 1

Process of eating food

1.ingestion- taking in food

2. Secretion- soluvising food and lubricating vesicles

3. Mixing and propulsion- contracts and relaxes to mix and propel food

4. Digestion- break down food

5. Absorbstion- take food from small intestines into blood stream

6. excretion- expulsion of non absorbed materials

Where does ingestion happen

In mouth

Where does secretion happen

in stomach and small intestines

where does mixing happen

In oral cavity, stomach and small intestines

Where does digestion happen

In oral cavity stomach and small intestines

Where does defaecation happen

In rectum and anus

What does the mobility arrow on diagram show

It represents the whole journey as to propel food throughout body we need a process called peristalsis

Where are enzymes released

in stomach and small intestines

Where are single compounds absorbed

Through GI wall to get transported to tissues, organs and muscles to become a processed nutrient

What’s number 1

Mouth

What’s number 2

Salivary glands

What’s number 3

Pharynx

What’s number 4

Oesophagus

What’s number 5

Gallbladder

What’s number 6

Liver

What’s number 7

Pancreas

What’s number 8

Stomach

What’s number 9

Duodenum

What’s number 10

Jejunum

What’s number 11

IIeum

What’s number 12

Appendix

What’s number 13

Caecum

What’s number 14

Ascending colon

what’s number 15

Transverse colon

What’s number 16

Defending colon

What’s number 17

Sigmoid colon

What’s number 18

Rectum

What’s number 19

Anus

What does a direct role mean

Whether it passes through a direct organ

What is indirect role

To provide a substance to aid in digestion

Examples of direct ones

Oral cavity

Oesophagus

Stomach

Small intestines

Large intestines

Rectum

Ants

Which play an indirect role

Teeth(chew)

tongue( swallow)

salivary glands (release of saliva for librication

Liver(aids digestion of fats)

Gallbladder (stores bile and responsible for emulsification of lipids

How many layers of the GI tract are there

4

What are the four layers

Inner mucosa

Submucosa

Muscularis mucosa

Adventitia

How many layers is the mucosa made up of

3 including epithelium, lamina propria and muscularis aggregates

What is the epithelium

the mouth and oseophagus has a stratified layer of epithelium for protection

The stomach and intestine has simple columnar so it doesn’t have to go through multiple layers to absorb food

What is the laminate propria

The connective tissue layer with elastic collagen fibres that allow epithelial lining to stay in place and there is blood supply, nerve supply and lymphatic supply

What is the muscularis mucosa

It constists of smooth muscle fibre and is non striated and responsible for creating folds in stomach and intestines to all stomach to increase or decrease capacity and has villi to maximise absorption capacity

What is the submucosa (second layer)

A layer of connective tissue which includes submucosal glands to aid in lubrication and protection of GI tract

Also contains meissners plexus which is responsible for nerve stimulation for muscularis macosae layer

What is muscularis mucosae later (third layer)

Make up of inner circular muscle and outer longitudinal muscle

Has a layer of oblique muscle to help churn stomach

Responsible for movement to vili so that there is maximum absorption capacity

Made up of skeletal and smooth muscle

Contains myenteric plexus- autonomic fibres that regulates mobility and frequency of contractions