GI_Lect24_motility
Pre-lecture material for proper note-taking
Not a substitute for live lectures
Lectures 24-27:
Lecture 24: Introduction to gastrointestinal physiology, motility, and mechanical digestion
Lecture 25: Secretion in the gastrointestinal tract
Lecture 26: Chemical digestion in the gastrointestinal tract
Lecture 27: Absorption of nutrients, water, and sodium in the gastrointestinal tract
Regulation of the gastrointestinal tract:
Enteric nervous system
Parasympathetic and sympathetic nervous systems
Hormonal regulation
Long and short reflex pathways in gastrointestinal control.
Motility patterns for food processing:
Chewing, peristalsis, relaxation, contraction, segmentation, and MMC.
Functions of gastrointestinal motility:
Mechanical digestion, propulsion, mixing, storage, controlled movement, and exposure to absorptive surfaces.
Motility patterns of the mouth, oesophagus, stomach, and intestines.
Motility: Movement of food/chyme through contraction and relaxation of muscles.
Secretion: Release of fluids, enzymes, and components aiding digestion.
Digestion: Breakdown of food into smaller components:
Mechanical and chemical digestion.
Absorption: Movement of nutrients across intestinal lining into circulation.
Nervous System Regulation:
Fast responses via ENS and muscle coordination.
Enteric Nervous System (ENS): Self-contained, operates independently.
Parasympathetic NS: Stimulates GIT activity (rest and digest).
Sympathetic NS: Inhibits GIT activity (fight or flight).
Hormonal Regulation: Endocrine responses that last longer:
Important hormones: Gastrin, Secretin, CCK, GIP.
Types of Contractions:
Tonic (sustained) and phasic (wave-like).
Motility during Feeding:
Chewing, peristalsis, relaxation (storage), segmentation (mixing), and sphincter control.
Fasting Motility:
Migrating Motor Complex (MMC): Housekeeping function post meal.
Mouth: Chewing (mastication).
Oesophagus: Peristalsis (propelling food).
Stomach: Retropulsion (mixing and mechanical digestion), relaxation to accommodate food.
Small Intestine: Segmentation (mixing) and peristalsis (propulsion).
Large Intestine: Storage and water absorption through segmentation and peristalsis.
Compliance with copyright regulations for course material.
Do not distribute or copy course content without permission.
Pre-lecture material for proper note-taking
Not a substitute for live lectures
Lectures 24-27:
Lecture 24: Introduction to gastrointestinal physiology, motility, and mechanical digestion
Lecture 25: Secretion in the gastrointestinal tract
Lecture 26: Chemical digestion in the gastrointestinal tract
Lecture 27: Absorption of nutrients, water, and sodium in the gastrointestinal tract
Regulation of the gastrointestinal tract:
Enteric nervous system
Parasympathetic and sympathetic nervous systems
Hormonal regulation
Long and short reflex pathways in gastrointestinal control.
Motility patterns for food processing:
Chewing, peristalsis, relaxation, contraction, segmentation, and MMC.
Functions of gastrointestinal motility:
Mechanical digestion, propulsion, mixing, storage, controlled movement, and exposure to absorptive surfaces.
Motility patterns of the mouth, oesophagus, stomach, and intestines.
Motility: Movement of food/chyme through contraction and relaxation of muscles.
Secretion: Release of fluids, enzymes, and components aiding digestion.
Digestion: Breakdown of food into smaller components:
Mechanical and chemical digestion.
Absorption: Movement of nutrients across intestinal lining into circulation.
Nervous System Regulation:
Fast responses via ENS and muscle coordination.
Enteric Nervous System (ENS): Self-contained, operates independently.
Parasympathetic NS: Stimulates GIT activity (rest and digest).
Sympathetic NS: Inhibits GIT activity (fight or flight).
Hormonal Regulation: Endocrine responses that last longer:
Important hormones: Gastrin, Secretin, CCK, GIP.
Types of Contractions:
Tonic (sustained) and phasic (wave-like).
Motility during Feeding:
Chewing, peristalsis, relaxation (storage), segmentation (mixing), and sphincter control.
Fasting Motility:
Migrating Motor Complex (MMC): Housekeeping function post meal.
Mouth: Chewing (mastication).
Oesophagus: Peristalsis (propelling food).
Stomach: Retropulsion (mixing and mechanical digestion), relaxation to accommodate food.
Small Intestine: Segmentation (mixing) and peristalsis (propulsion).
Large Intestine: Storage and water absorption through segmentation and peristalsis.
Compliance with copyright regulations for course material.
Do not distribute or copy course content without permission.