The document outlines the human digestive system, detailing the organs involved and their functions from ingestion to elimination. It describes the journey of food, highlighting the roles of organs such as the mouth, esophagus, stomach, small intestine, large intestine, liver, gallbladder, and pancreas. Additionally, it emphasizes the processes of digestion, absorption, and the significance of enzymes and acids in breaking down food.

1. THE HUMAN
DIGESTIVE
SYSTEM
THE BODY SYSTEMS

2. LET’S OBSERVE!
Each student is given two crackers.
• Step 1: Put a regular cracker into the
mouth and chew.
• Step 2: Place a new cracker in the mouth
and let it sit for 2 minutes.
Let’s discuss students’ observations:
• Initial feeling
• Changes after 2 minutes
• Chewing process
DID YOU KNOW?
On average, a person produces about 1 to 1.5 liters
of saliva per day!

3. RUBRICS

4. LESSON OBJECTIVES
Identify key components
such as the mouth,
esophagus, stomach,
intestines, liver, gallbladder,
and pancreas.
Explain the purpose of
digestion, absorption, and
elimination and how
enzymes and acids aid in
breaking down food into
nutrients.
Describe the journey of food
inside the body from the
mouth to the rectum and the
specific functions performed
at each stage.

5. LET’S DISCUSS
The digestive system in the human body processes
food and liquids. It consists of the digestive tract, where
food passes through structures like the mouth,
esophagus, stomach, small intestine, large intestine,
and accessory organs.
These organs work together to break down food into
smaller components for absorption and assimilation.
DIGESTIVE
SYSTEM

6. DIGESTIVE ORGANS
The mouth is the first organ in the digestive
system. It serves several essential functions:
• Ingestion: Food enters the mouth, allowing
the initial stage of digestion.
• Mechanical Digestion (Chewing): Teeth break
down large food pieces into smaller ones.
• Chemical Digestion: Saliva initiates digestion
by breaking down starch into sugar.
MOUTH

7. DIGESTIVE ORGANS
The esophagus ensures the smooth movement
of food from the mouth to the stomach,
allowing for efficient digestion and nutrient
absorption.
Unlike the stomach and small intestine, the
esophagus does not secrete digestive enzymes.
Its primary function is to facilitate the passage
of food.
ESOPHAGUS

8. DIGESTIVE ORGANS
he stomach is a hollow muscular organ that
holds food while it is being mixed with stomach
enzymes.
Its key functions include temporary food
storage, mechanical digestion (through
muscular contractions), chemical digestion (via
acids and enzymes), and controlled emptying of
partially digested food into the small intestine.
STOMACH

9. DIGESTIVE ORGANS
The pancreas is located behind the stomach; it
performs two key functions: it produces enzymes
that break down sugars, fats, proteins, and starches
during digestion.
The pancreas releases hormones into the
bloodstream. These chemical messengers help
regulate blood sugar levels, stimulate stomach
acids, and control appetite and stomach emptying.
PANCREAS

10. DIGESTIVE ORGANS
The liver, the largest organ in the body, performs
essential functions within the digestive system.
The liver continually produces bile, aiding fat
digestion and nutrient absorption. It processes
toxins and removes them from the blood. The liver
creates substances necessary for blood clotting
after injury. It helps maintain healthy blood sugar
levels.
LIVER

11. DIGESTIVE ORGANS
The gallbladder is a small, pear-shaped organ
located beneath the liver. Its primary role in the
digestive system is to store and concentrate bile
produced by the liver.
Bile is a sticky, yellow-green digestive fluid
produced by the liver and stored in the gallbladder.
Its primary function is to break down fats into fatty
acids during digestion.
GALLBLADDER

12. DIGESTIVE ORGANS
The small intestine's main functions include
breaking down food, absorbing nutrients, and
moving the intestinal contents along the digestive
tract. Specifically, the small intestine absorbs
carbohydrates, proteins, and fats. It plays a vital
role in digestion, ensuring efficient nutrient
absorption and waste elimination.
SMALL INTESTINE

13. DIGESTIVE ORGANS
The large intestine, also known as the colon, follows
the small intestine and extends to the anal canal,
where food waste exits the body. The large
intestine performs several essential functions, such
as absorbing water and electrolytes, forming stool,
facilitating bacterial fermentation, and protecting
against infections.
LARGE INTESTINE

14. DIGESTIVE ORGANS
The rectum connects the large intestine to the
anus. It acts as a reservoir where stool accumulates
before being ready for elimination. The anus marks
the exit point for food waste. Muscles, nerves, and
mucous membranes work together to facilitate
healthy bowel movements that you can control.
RECTUM AND
ANUS

15. THANK YOU
FOR
LISTENING!
ANATOMY CLASS

16. THE HUMAN
DIGESTIVE
SYSTEM
THE BODY SYSTEMS