Gastrointestinal System Flashcards
Gastrointestinal Functions
+ Fluid and Nutrient Pathway
+ Immune System Component
Fluid and Nutrient Pathway Outline
Ingestion Secretion Mixing and Propulsion Digestion Absorption Defecation/Elimination
Ingestion
+ Ingestion of outside materials begins in the mouth.
+ On average humans ingest 3-4 liters of liquid and 2k-3k of kcals/day.
Peristalsis
Contractions of smooth, longitudinal-layered muscles in digestive tract walls responsible for inch-wise movement of ingested material. (Push)
Segmentation
Contractions of muscles with circular fibers in digestive tract walls responsible for propulsion of ingested material. (Squeeze)
Mixing and Propulsion
Function/Goal: Interaction (mixing) of ingested material and secreted fluids as they move through the digestive tract.
Immune Function of GastroIntestinal System
GI System acts as a physical barrier between outside materials and the inside of the body.
Filtering what materials are absorbed and transported throughout the body.
Relations/Interactions: Lymphatic System, Cardiovascular System, Immune System
Lumen
central portion of the intestinal tube responsible for absorbing and transporting nutrients to the cardiovascular and lymphatic systems.
Lymphocytes
a type of white blood cells and are one of the body’s main type of immune cells. They are hosted by lymphoid tissue embedded in the gi walls.
Microbiome
the sum total genome (genetic material) of microbiota
Microbiota
fungi, bacteria, and protozoans which prove beneficial to the human micro ecosystem by:
+metabolizing substances
+synthesizing vitamins (natural produced not ingested)
+communicating with immune system
Elimination
aka Defecation.
material not absorbed in lumen are excreted through anal canal.
Absorption
the process of lumen moving ingested materials’ nutrients from outside the body into the body.
Digestion
the breaking down of ingested material.
- Physical - Teeth grinding material
- Chemical - Stomach acid breaking apart material
