I.Functions of the Digestive System

BIO102 Unit 2

Digestive System

Study Guide

I.Functions of the Digestive System

A.Ingest food

B.Digest food

C.Absorb nutrients

D. Elimination

II.Major Organs: Mouth

A.Functions of the Mouth:

1. Ingests

2. Moistens food

3. mastication

4. taste & smell

5. swallows food

B. Roof of the Mouth

2. hard palate

3. soft palate

4. uvula

5. tonsils

C. Salivary Glands

1. parotid glands

2. sublingual glands

3. submandibular glands

a. mumps

D. Saliva

1. Saliva contains:

E. Teeth

1. function:

2. Types

3. structure:

4. Diseases of teeth:

a. dental caries

b. gingivitis

c. periodontitis

II. Pharynx

D. swallowing:

1. reflex action

2. nasopharyngeal

3. epiglottis:

III. Esophagus

A. Location

B. collapsed state

C. role in digestion

D. peristalsis

IV. Tissue Layers of the Digestive Tract

A. Mucosa

1. lumen

B. Submucosa

C. muscularis

D. Serosa

V. Stomach

A. description

B. location

C. cardiac & pyloric sphincters

D. heartburn

E. gastric

F. ruggae

G. function of the stomach

VI. Gastric Juices

A. gastric glands

1. pepsin

2. hydrochloric acid

3. mucus

B. Stomach (More Stuff)

1. Ulcer

2. alcohol

3. Chyme

VII. Small Intestine

A. Description

B. location

C. Three segments

VIII. Duodenum

A. Receives chyme

B. Relationship to the pancreas & the liver

C. Functions:

1. chemical

2. absorption

3. transport

D. Pancreatic Juices in the Small Intestine

1. Sodium bicarbonate

2. carbohydraeases

3. lipases

4. nucleases

5. proteinases – trypsin

E. Intestinal Juices in the Small Intestine

1. proteinase

2. sucrase

3. maltase

4. lactase

F. Liver – Gall Bladder – Bile

1. bile

2. bile duct

3. bile emulsifies fat

G. bilirubin – bile pigments

1. waste product of heme

2. globin & iron

3. bilirubin

4. urobilinogen

IX. Jejunum

A. location

B. absorption of digested materials

C. villi

D. lacteals

E. blood capillaries

F. Digestive End Products

1. carbohydrates

2. proteins

3. lipids

4. nucleic acids

X. ileum

A. description:

B. location

C. function:

XI. Large Intestine

A. functions:

1. reabsorption of water

2. stores indigestible material

3. composition of feces

B. Parts of the Large Intestine

1. cecum

2. appendix

a. appendicitis

3. colon

a. ascending

b. transverse

c. descending

d. sigmoid

4. rectum

5. anal canal

D. Disorders of the Large Intestine

1. Diarrhea

2. constipation

3. food poisoning

XII. Accessory Organs

A. pancreas

1. description and location

2. functions as an exocrine gland

a. digestive enzymes

3. functions as an endocrine gland

a. secretes insulin & glucagons

B. Liver

1. description

2. location

3. composed of two main lobes

4. hepatic artery

5. hepatic portal vein

6. hepatic vein

C. Liver – More Stuff

1. functions:

a. detoxifies

b. removes & stores iron

c. removes & stores vitamins

d. stores glucose

e. converts hemoglobin

f. produces bile

D. Liver Disorders

1. jaundice

2. hepatitis

a. viral hepatitis A

b. viral hepatitis B

c. Hepatitis C

3. Cirrhosis

XIII. Nutrition

A. Macronutrients

B. Micronutrients

C. Carbohydrates

1. source of energy

2. blood glucose level

3. simple carbohydrates - “empty calories”

4. complex carbohydrates

D. Proteins

1. food sources

2. How it is used by our body:

3. essential vs non essential amino acids

4. complete protein source

E. Lipids

1. food sources

2. risk of cancer

F. Cholesterol

1. food sources

2. plaque

G. Vitamins

1. organic compounds

2. If lacking in diet (fig 12.16) page 230 - rickets, dermatitis, scurvy

3. Thirteen Vitamins divided into Fat soluble vitamins (Table 12.6) and water soluble vitamins (Table 12.7) page 231.

Vitamin A, Vitamin D, Vitamin K, folic acid, vitamin B12

H. Minerals

1. various minerals are required by the body (Table 12.8) page 233

calcium, potassium, sodium, iron, iodine

2. calcium

3. sodium

4. iron

XIV. Eating Disorders

A. Obesity

B. Bulimia

C. Anorexia Nervosa