16. Digestive System Flashcards
ds
Functions of Digestive System
- Ingestion
- DIgestion
- Absorption
- Elimination
Consists of digestive tract (gastrointestinal tract) plus associated organs.
Digestive SYstem
What are these?
1. Oral cavity or mouth
2. Pharynx (throat)
3. The esophagus
4. The stomach
5. Small and large intestines
6. Anus
Digestive Tract
The stratified epithelium protects them from the abrasion of chewing and swallowing
Oral Cavity and the Esophagus
The columnar epithelium (absorption of nutrients and secretion of digestive fluids)
Stomach and Intestine
Four major tunics or layers of digestive tract
- Mucosa
2.Submucosa - Muscularis
- Serosa
Serous membrane that covers the organ
Peritoneum
Connective tissue sheets that hold in place the organs of the abdominal cavity.
Mesenteries
Life-threatening inflammation of the peritoneal membranes
Peritonitis
Bounded by the lips and cheeks which contains the teeth and tongue
Oral Cavity/Mouth
Reddish-pink appearance that formed mostly by the orbicularis oris muscle.
Lips
Form the lateral walls of the oral cavity
Cheeks
Large muscular organ that occupies most of the oral cavity which is covered by the papillae, some of which contain taste buds
Tongue
32 in normal adult mouth and is located in mandible and maxillae.
Teeth
Regions of tooth
- Crown (the visible portion)
- Neck (small region between the root and crown)
- Root (largest region of the tooth
Within the center of the tooth
Pulp Cavity
Breakdown of enamel by acids produced by bacteria on the tooth surface
Dental Caries/Tooth Decay
Roof of the oral cavity which prevents the food from passing into the nasal cavity
Palate
Front-line defense forming the initial immunological response to inhaled or ingested pathogens
Tonsils
3 Major of pairs of salivary glands
- Parotid Glands
- Submandibular Glands
- Sublingual Glands
Inflammation of the parotid gland caused by a viral infecion
Mumps
A versatile fluid that helps keep the oral cavity moist and contains enzymes.
Saliva
Digestion of polysaccharides by salivary amylase enhances the sweet taste of food
Salivary Amylase
Mildly antibacterial enzyme that prevents bacterial infections in the mouth
Lysozyme
Chewing by the teeth which breaks the large food particles into many small ones to increase surface area
Mastication
Connects the mouth with the esophagus
Pharynx
This has 3 phases:
1. Voluntary Phase
2. Pharyngeal Phase
3. Esophageal Phase
Swallowing
Muscular tube, lined with moist stratified squamous epithelium
Esophagus
-Primarily houses food for mixing with hydrochloric acid and other secretions
-enlarged segment of the digestive tract
Stomach
Stomach Secretions from the Gastric Glands include:
- Hydrochloric Acid
- Pepsin
- Mucus
- Intrinsic Factor
Kills microorganism and activates the enzyme, pepsin.
Hydrochloric Acid
Breaks covalent bonds of proteins
Pepsin
Forms a thick layer, which lubricates the epithelial cells of the stomach wall
Mucus
Binds with vitamin b12
Intrinsic Factor
A painful or burning sensation in the chest
Heartburn or Gastritis
2 Types of Stomach Movement
- Mixing Waves
- Peristaltic Waves
The major site of digestion and absorption of food
Small Intestine
4 Major Cell Types of the Small Intestine’s Mucosa
- Absorptive Cells (produce digestive enzymes)
- Goblet Cells (produce a protective mucus)
- Granular Cells (protect the intestinal epithelium)
- Endocrine Cells
(produce regulatory hormones)
Largest internal organ of the body
Liver
There are two lobes of the liver which are the right and left lobe. What separates the two lobes?
Falciform Ligament
What are the two sources of blood
- Hepatic Artery
- Hepatic Portal Vein
What are these?
1. Digestive and secretion
2. Storage and processing of nutrients
3. Detoxification of harmful chemicals
4. Synthesis of new molecules
Functions of the Liver
An important contributor to the liver’s digestive functions
Bile
A complex organ composed of both endocrine and exocrine tissues that perform several functions
Pancreas
This is a lipid-digesting enzyme
Lipase
The large intestine is consist of: CCRA
Cecum, colon, rectum, anal canal
This facilitates the transit of ingested material, requiring approximately 18-24 hours for completion
Large Intestine
What are these:
1. Feces Formation
2. Microbial Activity
3. Mass Movements
4. Defecation Reflex
Functions of the Large Intestine
The breakdown of food molecules that are small enough to be absorbed into the circulation
Digestion
A digestion that breaks arge food particles into smaller ones
Mechanical Digestion
Uses enzyme to break covalent chemical bonds in organic molecules
Chemical Digestion
Consists primarily of starches, cellulose, sucrose and small amounts of fructose
Carbohydrates
an energy storage molecule in plants
Starch
Forms the walls of plant cells
Cellulose
An energy-storage molecule in animals and is contained in muscle and in the liver.
Glycogen
-Insoluble or only slightly soluble in water
-include triglycerides, phospholipids steroids, and fat-soluble vitamines
Lipids
Secreted by the pancreas, digest lipid molecules
Lipase
chains of amino acids found in most of the plant and animal products we eat
Proteins
Any change in bowel habits involving increased stool frequency or volume or increased stool fluidity.
Diarrhea
