Sistema Digestivo: Introducción y Etapas

Study Notes

Introduction

Digestion is the process of breaking down food into smaller molecules absorbable into the bloodstream.
This process is essential for providing the body with nutrients needed for proper function.
The human digestive system is a complex series of interacting organs and processes for achieving digestion.

Stages of Digestion

Ingestion: Taking food into the mouth.
Mechanical Digestion: Physical breakdown of food.
- Chewing (mastication) breaks food into smaller pieces.
- Peristalsis (rhythmic smooth muscle contractions) moves the food through the digestive tract.
Chemical Digestion: Breakdown of food using enzymes.
- Starts in the mouth with salivary enzymes.
- Continues in the stomach and small intestine with various enzymes from the pancreas and intestinal cells.

Organs of the Digestive System

Mouth: Initiates digestion with chewing and saliva.
Pharynx (Throat): Passageway for food from the mouth to the esophagus.
Esophagus: Muscular tube transporting food to the stomach.
Stomach: Stores food, mixes it with gastric juices (containing hydrochloric acid and enzymes).
- Acidic environment kills bacteria.
- Protein digestion begins.
Small Intestine: Main site of nutrient absorption.
- Long, folded structure maximizes surface area.
- Numerous digestive enzymes break down carbohydrates, proteins, and fats.
- Bile from the liver and gallbladder emulsifies fats.
Large Intestine: Absorbs water and electrolytes.
- Forms and stores feces.
- Contains beneficial bacteria.
Liver: Produces bile, essential for fat digestion.
- Filters blood and detoxifies substances.
Pancreas: Produces enzymes for carbohydrate, protein, and fat digestion.
- Also releases bicarbonate to neutralize stomach acid.
Gallbladder: Stores and concentrates bile.
- Releases bile into the small intestine when needed.

Digestive Enzymes

Amylase: Breaks down carbohydrates.
Proteases: Break down proteins.
Lipases: Break down fats.
Pepsin: Enzyme active in the acidic stomach environment.

Absorption

Nutrients are absorbed through the intestinal lining into the bloodstream.
- Simple sugars, amino acids, fatty acids, and vitamins are absorbed.
Absorption primarily occurs in the small intestine due to its large surface area.

Elimination

Undigested food and waste products are eliminated from the body as feces.
The large intestine absorbs water and forms feces.
Feces are expelled through the anus.

Disorders of the Digestive System

Heartburn: Acid reflux from the stomach into the esophagus.
Ulcers: Sores in the stomach or duodenal lining.
Constipation: Difficulty passing stool.
Diarrhea: Frequent passage of loose, watery stools.
Irritable bowel syndrome (IBS): Disorder affecting the large intestine.
Gastroesophageal reflux disease (GERD): Chronic symptom of acid reflux.
Crohn's disease: Inflammatory condition of the digestive tract.
Celiac disease: Autoimmune disorder triggered by gluten.

Factors Affecting Digestion

Diet: A balanced diet is critical for optimal digestion.
Stress: Stress can impact digestive function, possibly leading to issues like ulcers and IBS.
Medications: Certain medications can cause digestive side effects.
Hydration: Adequate water intake aids digestion and prevents constipation.
Activity Level: Regular exercise promotes regularity and digestion.

Description

Este cuestionario explora el proceso de digestión, que descompone los alimentos en moléculas más pequeñas. Aprenderás sobre las etapas de la digestión, los órganos involucrados y cómo funcionan juntos para proporcionar nutrientes al cuerpo. Ideal para estudiantes de biología o interesados en la anatomía humana.