Exam 4: Digestive System Flashcards Preview

Anatomy A-215 > Exam 4: Digestive System > Flashcards

Flashcards in Exam 4: Digestive System Deck (58)
Loading flashcards...
1

Gastrointestinal (GI) Tract

-tube that extends from mouth to anus
-mouth, pharynx, esophagus, stomach, small intestine, large intestine, and anus

2

Functions of GI Tract

-digestion
-absorption
-elimination of wastes

3

Digestion

-process of breaking down food into small fragments
-2 types mechanical and chemical

4

Mechanical Digestion

-using forces/physically breaking down food
-Ex: stomach mechanically digests by muscle contraction

5

Chemical Digestion

-uses enzymes (proteins) that speed up a chemical reaction
-Ex: stomach chemically digests with gastric juices

6

Absorption

-water and food molecules pass through to GI lymphatics and blood vessels
-most nutrients absorbed in blood vessels

7

Lacteals

-absorb lipids and lipid soluble vitamins in small intestine (A, D, E, K)

8

Accessory Digestive Organs

-not part of GI tract but assist with digestion
-tongue, teeth, salivary glans, liver, gallbladder, pancreas

9

Peritoneum

-serous membrane that lines the abdominal cavity
-parietal lines abdominal wall
-visceral covers abdominal organs
-peritoneal cavity is the space between the two, serous fluid secreted here

10

Parasympathetic Innervation

-in general, it stimulates or increases activity of GI tract

11

Sympathetic Innervation

-in general, it inhibits or decreases activity of GI tract

12

Oral Cavity

-continuous posteriorly with oropharynx
-nonkeratinized stratified squamous epithelium
-upper part of the oral cavity: palate

13

Hard Palate

-anterior 2/3 of palate, bony

14

Soft Palate

-posterior 1/3 of palate, formed from skeletal muscle

15

Uvula

-dangling muscle off soft palate

16

Extra Credit Names

-Osmosis Jones and Drix

17

Function of Soft Palate and Uvula

-close off opening to nasopharynx when you swallow
-these muscles move and that's why milk goes up your nose

18

Teeth

-20 deciduous (baby) teeth replaced by 32 permanent teeth

19

Tongue

-big skeletal muscle
-covered with stratified squamous epithelium
-function: perceives taste and mechanical digestion

20

Salivary Glands

-3 pairs
-secrete saliva composed of water, mucus, amylase (digests carbs), lysozyme (antibacterial agent) and antibodies
-functions: dissolves food molecules so they can be tasted, moistens food and turns it into bolus, chemically digests carbs, cleanses mouth, lysozyme and antibodies inhibit bacterial growth

21

Pharynx

-throat
-muscular tube that connects nasal cavity and mouth, to larynx and esophagus
-function: propel food and drink to esophagus and air to larynx
-only the oropharynx and laryngopharynx conduct both food and air

22

GI Tract Layers

-4 layers, tunics
-mucosa, submucosa, muscularis, adventita/serosa

23

Mucuosa

-innermost tunic
-esophagus has nonkeratinized stratified squamous epithelium
-stomach to anal canal has simple columnar epithelium
-areolar CT

24

Muscularis Mucosae

-thin layer of smooth muscle

25

Submucosa

-connective tissue
-contains major blood vessels

26

Muscularis

-typically contains 2 layers of smooth muscle:
-exception: stomach (3 layers)
-inner circular layer
-outer longitudinal layer
-responsible for peristalsis: alternate waves of contraction and relaxation

27

Serosa or Adventitia

- outermost layer
-serosa = visceral peritoneum + areolar CT
-adventitia = areolar CT only

28

Esophagus Gross Anatomy

-muscular tube that connects pharynx to stomach
-function:propel food to stomach

29

Esophagus Histology

-mucosa: nonkeratinized stratified squamous epithelium
-muscularis: 2 layers of muscle
-upper 1/3: skeletal muscle
-middle 1/3: skeletal + smooth
-lower 1/3: smooth muscle only

30

Reflux Esophagitis

-heartburn
-stomach contents back flow (reflux) into esophagus causing burning pain
-risk factors: overweight, smoking, large meals before bedtime