ML

Digestive System Notes

Digestive System Overview

  • Basic Terms:
    • Esophagus: A tube connecting the stomach to the mouth (indicating the path food takes during digestion).
    • Dia: Meaning across/through; Diaphragm separates thoracic from abdominal cavity.
    • Gastro: Refers to the stomach.

Key Components of the Digestive System

  • Spleen Terms:
    • Spleno, Lino: Terms for spleen.
  • Liver: Known as hepatoma.
  • Gallbladder: Identified with cholecysto; inflammation termed cholecystitis (inflammation of the gallbladder).

Small Intestine Structure

  • Parts of Small Intestine:
    • Duodenum: First part; literally means twelve.
    • Jejunum: Second part, five feet long; means to empty.
    • Ileum: The longest part, around 15 feet, means twisted.
    • Functionally involved in nutrient absorption and bile processing.

Larger Intestine Components

  • Colon Sections:
    • Transverse Colon: Lateral extension.
    • Ascending Colon: Extends upward from cecum.
    • Descending Colon: Extends downward toward sigmoid.
    • Sigmoid Colon: Named for its S shape (sigmoid refers to Greek "S").
    • Rectum: Straight tube leading to the anus (2.5 inches long).
    • Cecum: First part of the large intestine, where small intestine attaches.

Abdominopelvic Cavity

  • Cavities:
    • Major: Cranial, thoracic, abdominal, pelvic.
    • Minor: Sinuses, ear cavity.
  • Divisions: Abdominopelvic cavity can be split into quadrants or regions using anatomical landmarks:
    • Uses the patient's perspective (right/left).
    • Four Quadrants created by lines through the navel and pubic area.

Nine Regions of the Abdomen:

  • Umbilical Region: Central area around the navel.
  • Lumbar Regions: Right and left sides of the umbilical region.
  • Epigastric Region: Area above the umbilical (stomach).
  • Hypogastric Region: Below umbilical (below the stomach).
  • Iliac Regions: Sides of the hypogastric area.

Anatomy and Function of the Tongue

  • Covers multiple physiological functions:
    • Taste Recognition: Sweet, salty, sour, bitter.
    • Roles: Mastication, swallowing, articulating speech.
  • Structures:
    • Papillae: Contain taste buds.
    • Lingual Tonsils: Immune function at the back of the tongue.
    • Epiglottis: Covers glottis during swallowing.

Teeth Anatomy

  • Types of Teeth:
    • Incisors: Front teeth.
    • Cuspids: Canine teeth.
    • Premolars: Flattened teeth for grinding food.
    • Molars: Major grinding teeth in the back.
  • Structure: Composed of enamel, dentin, pulp.
    • Gingivitis: Gum inflammation; affects tooth stability.

Small Intestine Absorption

  • Villi: Tiny structures increase surface area for nutrient uptake.
    • Lacteals: Absorb fats into the lymphatic system.
  • Mesentery: Anchors the intestines; critical for nutrition absorption.

Colon Functionality

  • Function: Absorbs water, processes waste material.
  • Conditions:
    • Irritable Bowel Syndrome (IBS), Ulcerative Colitis, Amebiasis.
  • Sigmoidectomy/Sigmoidostomy: Surgical interventions for sigmoid colon issues.

Importance of Peristalsis

  • Facilitated by fibrous foods; essential for proper digestion and elimination.
  • Too much or too little fluid absorption can cause constipation or diarrhea.
  • Primary Bacteria: Escherichia coli plays a critical role in gut health.

Overview of Common Digestive Disorders

  • Irritable Colitis, Diverticulitis: Inflammation issues in the colon.
  • Polyp Formation: Can lead to malignant conditions (colon cancer).

These notes cover the major elements of the digestive system with detailed information on structure, function, and related medical terminology that can help in understanding and preparing for related examinations or discussions.