Digestive Flashcards
Why do we need food?
We need food so that we can produce glucose. A component that is very important for cellular respiration and for the creation of energy.
What is the process of digestion?
Ingestion Secretion Digestion Absorption Compaction Excretion
What is the GENERAL histology of the digestive tract?
- Mucosa
- Submucosa
- Muscularis externa
- Serosa OR adventitia
What determines if an organ has Serosa or Adventitia?
If the organ is found in the PERITONEAL CAVITY the lining is SEROSA
If the organ is not in a true serous body cavity the lining is ADVENTITIA.
What is the general anatomy of the oral cavity?
Oral mucosa Hard palate Soft palate Tongue, teeth Salivary glands
What are the general functions of the oral cavity?
Sensory analysis
Mechanical digestion
Chemical digestion
Lubrication
General anatomy of the tongue?
Superior side: lingual papillae
Inferior side: Frenulum (tongue web)
General functions of the tongue?
Mechanical digestion
Manipulation
Sensory analysis
Secretion of mucin and lingual lipase
What are the 3 types of salivary glands?
Parotid gland
Sublingual gland
Submandibular gland
Function of salivary gland?
Break down carbohydrates w/ enzymes
Flushing out bacteria
Lubrication
What is a baby tooth called?
Deciduous teeth
What are the different types of teeth?
Incisors
Cuspids
Bicuspids
Molars
Function of the teeth
Mastication
Breaking tough connective tissue of meat and plant fibers
What are the parts of a tooth?
Enamel Dentin Cement Pulp Root canal
What is the scientific word for swallowing?
Deglutition
What are the phases of Deglutition?
Buccal phase
Pharyngeal phase
Esophageal phase
Final phase
What happens during the Buccal phase of Deglutition?
Chewed food is called bolus
Bolus is pushed against hard palate by tongue
Soft palate lifts up blocking nasal cavity
What happens during the Pharyngeal phase of Deglutition?
Epiglottis folds down over larynx
Bolus moves posteriorly toward esophagus
Momentary stop in breathing
What happens during the Esophageal phase of Deglutition?
Upper esophageal sphincter opens
Peristaltic waves moves bolus down towards stomach
What happens during the final phase of Deglutition?
Lower esophageal sphincter opens
Bolus enters stomach
What is the histology of the Esophagus?
Stratified squamous epithelium w/ large folds
What are the four regions of the stomach?
Cardiac
Fundus
Body
Pyloric
Where does the pyloric sphincter lead to?
The small intestines
What is the function of the stomach?
Store ingested food
Mechanically digest food
Chemically digest food to create chyme.
What is the histology of the stomach?
Simple columnar epithelium
Rugae
Gasteric pits
What is rugae?
circular folds in the stomach
What is the function of gastric pits?
Secrete acids
Secrete mucous into the lumen
What kind of gland is a gastric gland?
Simple branched tubular gland
What do gastric glands secrete?
Mucous neck cells
Parietal cells
Cheif cells
G cells
What are the 3 regions of the small intestine?
Duodenum
Jejunum
Ileum
Absorption happens in what region of the small intestine?
Jejunum
What is the function of the small intestine?
Final chemical digestion
90% of nutrient absorption
What is special about the mucosa of the small intestine?
It has permanent circular folds that increase surface area
What is the histology of the small intestine?
Permanent circular folds
Simple columnar epithelium line intestinal villi
Microvilli found at apical surface of epithelial cells
Goblet cells secrete mucin
Lamina propria contains capillaries, nerves and lacteals
What are the 3 regions of the Large intestine?
Cecum
Colon
Rectum
What are the 4 regions of the colon?
Ascending colon
Transverse colon
Descending colon
Sigmoid colon
What is a houstra?
“pouches” in the colon
What are the functions of the large intestine?
Water absorption
House bacteria
Fecal storage before elimination
How does food pass through the stomach to the rectum?
The PYLORIC SPHINTER of the STOMACH leads to the SMALL INTESTINE.
The ILIUM of the SMALL INTESTINE leads to the LARGE INTESTINE.
The SIGMOID COLON leads to the RECTUM
Histology of colon
No intestinal villi More goblet cells than small intestine Deeper intestinal glands Large lymph nodules Has bands called teniae coli
General anatomy of the Rectum
Last 15cm of large intestine
Temp. stores feces
Last portion is the anal canal, that leads to the anus
KERATINIZED STRAITIFIED SQUAMOUS EPITHELIUM to prevent rectum/anus from abrasion
What are the two circular muscle rings in the rectum?
Internal anal sphincter
External anal sphincter
What are the accessory digestive organs?
Liver
Gall bladder
Pancreas
What is the function of the liver?
Produce bile to break down fat
What are the four lobes of the liver?
Right and left lobe (frontal)
Caudate lobe and quadrate lobe (posterior)
What is the right and left lobe of the liver separated by?
Falciform ligament
What is a hepatocye?
Liver cell
What does the “portal triad” consist of?
Hepatic artery ( into) Hepatic vein (into) Bile duct. (out)
What is the pathway of bile?
Produced by hepatocyes, leaves via bile canaliculi
Bile ducts
Left and right hepatic ducts
Left and right common hepatic duct
Where is the pancreas located?
Directly below the stomach
What are the three subdivisions of the pancreas?
Head
Body
Tail
What is the major DIGESTIVE function of the pancreas?
Produce enzymes that break down chime into absorbed nutrients
Secretes buffer to raise PH to active/deactivate enzymes
What are the 5 “mesentery organs”
Lesser omentum Greater omentum Mesentery proper Mesocolon Falciform ligament
Location of the lesser omentum?
Between stomach and liver
Location of the greater omentum?
below stomach
What does the mesentery proper suspend?
Small intestine
Where is the falciform ligament between?
the liver and the diagram
