Digestion Part 1 intro-stomach

Question 1

What are the 5 stages of digestion?

Answer 1

The digestive system is the oragn system which processess food, extract nurit., eleiminate waste
1. Ingestion: intake food
2. digestion: mechanical and chemical breakdown of food into unesbale components
3. Absorbtion: uptake of usebale nuirtents into epithelia cells –> blood or lymph
4. Compaction: absobtion of water and consolidinating into feces
5. Defecation: eleimnation of feeces

Question 2

Two types of digestion

Answer 2

1. mechanical digestion: the physical breakdwon of food into smaller particles ( cutting and grinding of the teeth and by churning and pummeling from stomach and small intensine contractions)
2. Chemical Digestion: sereis of hydrolysis reactions that breakdown complex molcules into useable components ( digestuve enzymes made by salivary glands, stomach, small intestine)

Question 3

Digestive structures divisiosn

Answer 3

1. The Digestive Tract: Mouth–> pharynx–> esophagus–> stomach–> small inte–> large int–> anus
2. Acessory structures: Teeth, Tongue, Salivary Gland, Liver, Gallbladder, Pancreas ( not part of the contininous tube)

Question 4

Layers of the digestive tract

Answer 4

1. Mucosa (innermost)
   - Epithelium: straified squamos from mouth to epsophagus and lower anal canal –> Simiple Columnar (globelt cells)–> stratified squamos (anus)
   - Lamina Propia: loose areolar tissues
   - Muscularis interna/mucosa: smooth muscle
2. Submucosa ( Irregular connective tissue: glands , nerves, blood vess, nereve plexus, secreete mucus)
3. Muscularis Externa:
   - Innermost cirular muscle for peristalsis
   - outermost longitutional muscle for squeeze push
4. Serosa
   - Areolar (thin)
   - Surronded by simiple squamos
   Can operate outside: plexuses isolate inflammation

Question 5

What are the mesenteries and omenta tissues?

Answer 5

1. Mesenteries help to prevent the digestive tract from twisting itself and provides clear passgeway for nerves and vessles, lymph nodes
   - Stomach and intestines suspended in mesenteries
2. Omenta: fatty blanklets that cover the intestines:
   - Tow omenta in stomach
   - Greater omnetum hang from greater curvature and over small intes.
   - lesser omentum extends liver to lesser curvanture+ stomach.

Question 6

Mouth

Answer 6

• Oral and vacity functions in ingestion, taste, chemical digestion, smallowing, speech, respiration
• Lined with stratfied squamos epithelium that is kertanized for high absration (gums, cheek, hard palate)
• Cheeks and lips retain food , push back for chewing

Question 7

Tongue

Answer 7

• The tongue functions to manipulate food between teeth and is senistive
• Covered by non-kertanized stratified squamos epithelium
• projections called Linguinal Papillae (taste buds) functions to increase surface are for food contact and move bolus.
• Liguinal glands