Access Prior Knowledge

1. Access Prior Knowledge 1. What happens in the air sacs and the capillaries 
that surround them? 2. Name the parts of the respiratory system. Review previous outlines and write one 
question to ask classmates.

2. Digestive System The digestive system breaks 
down the food into very small 
materials so that the food can 
enter your cells. Your digestive system is made 
up of many organs that work 
together to help digest food.

4. Mouth and Esophagus The first step in digestion is chewing 
the food which is done with your teeth. Saliva also helps breaking down 
food in your mouth by using chemicals 
in the liquid. When you swallow the food it enters 
your esophagus and the muscles 
there push and squeeze the food into 
the stomach through this tube.

5. Stomach and Intestines Walls of the stomach can stretch to store food 
and the stomach produces fluids that help in 
digestion. The stomach squeezes the food into the small 
intestines where it receives chemicals from the two 
organs, the pancreas and liver, which help in 
digestion. The walls of the small intestine are lined with 
structures called villi, which are shaped like fingers 
to provide more surface area to absorb food. When digestion is finished, the particles of 
digested food move into the blood vessels in the 
small intestines. The food that is not digested moves into the large 
intestine where it takes water and salts from the 
waste to make it solid.

6. Urinary System The urinary system removes waste 
from your blood through two organs 
called the kidneys. The kidneys clean the blood, 
regulate the level of salt in the blood 
and control the level of water in the 
blood. The urinary bladder stores a mix of 
wastes and water (urine), until it is 
ready to leave the body.

7. TextQuest 1. What is the job of the digestive system? 2. List two functions your teeth do in the first part of the 
digestive process. 3. Name the structure of the small intestine that shaped 
to provide more surface area to absorb food. 4. How do the kidneys regulate the amount of water in 
the blood? 5. Where do the mixture of water and waste get stored 
before leaving your body?