digestive system

• Mouth


  The first step in digestion where food is chewed and mixed with saliva containing enzymes to break down carbohydrates.
• Esophagus


  A muscular tube that carries food from the mouth to the stomach.
• Stomach


  A sac-like organ where food is mixed with stomach acid and digestive enzymes to break down proteins and fats.
• Small Intestine


  A long, thin tube where nutrients are absorbed into the bloodstream.
• Large Intestine (Colon)


  Where water and electrolytes are absorbed, and waste is formed.
• Liver


  The organ that produces bile salts to aid in fat digestion and absorption.
• Pancreas


  The organ that produces digestive enzymes and hormones to regulate digestion.
• Amylase


  An enzyme in saliva that breaks down starches into simple sugars like glucose.
• Lipase


  An enzyme in saliva that breaks down fats into fatty acids and glycerol.
• Purpose of Digestion


  To break down food into smaller molecules that can be absorbed and used by the body for energy, growth, and repair.
• Benefit 1: Nutrient Absorption


  Breaking down food into smaller molecules allows the body to absorb essential nutrients like carbohydrates, proteins, and fats.
• Benefit 2: Energy Production


  Breaking down complex molecules into simpler ones allows the body to convert them into energy for daily activities.
• Benefit 3: Waste Removal


  The body can remove waste products and excess nutrients through the large intestine and excretory system.
• Benefit 4: Maintaining Homeostasis


  Proper digestion helps maintain the body's internal balance and keeps bodily functions stable.
• Citric Acid Cycle (Krebs Cycle)


  Breaks down pyruvate into acetyl-CoA, producing more ATP and NADH.
• Glucose Breakdown (Glycolysis)


  Breaks down glucose into pyruvate, producing a small amount of ATP.
• Oxidative Phosphorylation (Electron Transport Chain)


  Uses the energy from NADH and FADH2 to produce ATP from ADP and Pi.
• Energy Source for Cellular Respiration

  Glucose (C6H12O6)
• What is the primary function of the digestive system?

  To break down food into glucose
• What is the process by which cells break down glucose?

  Cellular respiration
• What is digestion?

  The breakdown of food into simple sugars
• What are the main processes involved in digestion?

  • Ingestion
  • Mechanical digestion
  • Chemical digestion
  • Absorption
  • Elimination
• Where does ingestion occur?

  In the mouth
• How do teeth contribute to digestion?

  They break down food into smaller pieces
• What is mechanical digestion?

  The physical breakdown of food
• What role does saliva play in digestion?

  It contains amylase to break down food
• What is peristalsis?

  Involuntary muscle contraction to move food
• What is the esophagus?

  A muscular tube connecting throat to stomach
• What is a sphincter?

  A muscle that controls substance passage
• What happens in the stomach during digestion?

  Mechanical and chemical digestion occurs
• What is chyme?

  A pulp of acidic fluid and food
• What are the four main regions of the stomach?

  • Cardia
  • Fundus
  • Body
  • Pylorus
• What is the role of amylase?

  Breaks down carbohydrates in saliva
• What is the function of the pyloric sphincter?

  Controls stomach emptying into the duodenum
• What is the primary function of the small intestine?

  Absorption of nutrients into the bloodstream
• What is the alimentary canal?

  Mouth to anus digestive tract
• What is the duodenum?

  First section of the small intestine
• What enzymes are secreted by the pancreas?

  Lipase and trypsin for digestion
• What is bile and where is it produced?

  Breaks down lipids; produced by the liver
• What is the jejunum's role in digestion?

  Most nutrient absorption occurs here