The Human Digestive System Worksheet

Have you ever thought about how all that yummy food makes its way through your body, and where it goes?

MMMmmm! Yummy!

Palte of food

Well, you probably know where some of it ends up!

Toilet

But where does the rest of it go?

Why do we need to eat?

In this worksheet, you are going to learn about our digestive system.

This is what we call the area in our body that deals with all the food that goes into our body and goes out of our body.

Digestive system

Use this diagram to help you answer the following questions.

The mouth is the first part of the digestive system.

Which important actions take place in here?

Tick three answers.

Mouth

teeth start to chew our food

the tongue collects the food at the front of the mouth

saliva starts to break down the food

food is swallowed

Where is our saliva, or spit, made?

in our tongue

in our stomach

in our salivary glands

What connects our mouths to our stomachs?

small intestine

esophagus

large intestine

Look at this diagram.

Stomach

Name the different parts.

Column A	Column B
A	esophagus
B	stomach
C	small intestine

Look at this diagram.

Stmach with labels

Match the statements below.

Column A	Column B
saliva	a thick mass of partly digested food formed in the...
gastric acid	contains special chemicals that start the breakdow...
chyme	a special liquid made by the stomach, which breaks...

Read this information. It will help you answer questions 6–8.

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After leaving the stomach, the partly digested food enters the duodenum, the first part of the small intestine. Digestive juices, made in the pancreas, enter the duodenum and help to further break down the chyme. The food molecules then pass through the rest of the small intestine. This is where the absorption process takes place: nutrients and minerals are absorbed through the lining of the intestine into the bloodstream. From here the blood passes through the liver, which cleans the blood, removing any toxins (poisons). The liver also makes a substance called bile which helps to break down any fats in our food. The gall bladder stores the bile that is made by the liver.

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Where are the food molecules absorbed into the body?

in the small intestine

in the pancreas

in the liver

What do the nutrients and minerals get absorbed into?

the skin

the blood

the liver

Why is the liver important?

Tick two answers.

it makes bile which breaks down fats

it cleans toxins out of the blood

it holds absorbed food

Undigested food passes out of the small intestine, into where?

into the blood

into the large intestine

into our saliva

What do you think happens in the large intestine?

Toilet roll

undigested food forms feces (poo)

undigested food returns to the stomach

ANSWERS

Question 1

The mouth is the first part of the digestive system.

Which important actions take place in here?

Tick three answers.

Mouth

CORRECT ANSWER

teeth start to chew our food
saliva starts to break down the food
food is swallowed

EDDIE SAYS

Our teeth break down the food into smaller pieces. Enzymes in saliva (spit) also start to break the food down. Once the food has started to break down we can taste it on our tastebuds. We swallow the food and it passes into the next part of the digestive system.

ANSWERS

Question 2

Where is our saliva, or spit, made?

CORRECT ANSWER

in our salivary glands

EDDIE SAYS

Spit, or saliva, is made in the salivary glands. These are located in the sides of our mouth and under our tongue and are stimulated to release saliva into the mouth by the smell or arrival of food.

ANSWERS

Question 3

What connects our mouths to our stomachs?

CORRECT ANSWER

esophagus

EDDIE SAYS

The esophagus (or oesophagus) is the tube that connects our mouths to our stomachs. It used to be known as the gullet.

ANSWERS

Question 4

Look at this diagram.

Stomach

Name the different parts.

CORRECT ANSWER

Column A	Column B
A	esophagus
B	stomach
C	small intestine

EDDIE SAYS

Yes, the tube down which food reaches the stomach is the espohagus. The stomach itself is the organ where much of the major work of breaking down food takes place. When it is ready, the partially-digested food is passed into the small intestine (this part being known as the DUODENUM).

ANSWERS

Question 5

Look at this diagram.

Stmach with labels

Match the statements below.

CORRECT ANSWER

Column A	Column B
saliva	contains special chemicals that s...
gastric acid	a special liquid made by the stom...
chyme	a thick mass of partly digested f...

EDDIE SAYS

Gastric acid is made in the stomach. It helps break down the food in your stomach into digestible molecules. The churning action of your stomach also helps break down the food. The thick liquid of partly digested food and molecules is called chyme and this is passed into the small inestine for final digestion and absorption of food.

ANSWERS

Question 6

Read this information. It will help you answer questions 6–8.

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After leaving the stomach, the partly digested food enters the duodenum, the first part of the small intestine. Digestive juices, made in the pancreas, enter the duodenum and help to further break down the chyme. The food molecules then pass through the rest of the small intestine. This is where the absorption process takes place: nutrients and minerals are absorbed through the lining of the intestine into the bloodstream. From here the blood passes through the liver, which cleans the blood, removing any toxins (poisons). The liver also makes a substance called bile which helps to break down any fats in our food. The gall bladder stores the bile that is made by the liver.

******************

Where are the food molecules absorbed into the body?

CORRECT ANSWER

in the small intestine

EDDIE SAYS

In the part of the small intestine where food passes in from the stomach, further digestion takes place. As it moves along, the fully digested food is absorbed across the wall of the gut into the bloodstream.

ANSWERS

Question 7

What do the nutrients and minerals get absorbed into?

CORRECT ANSWER

the blood

EDDIE SAYS

When the food has been digested into tiny molecules, they are small enough to be absorbed across the gut wall and into the blood. Then they travel off around the body to deliver their energy store.

ANSWERS

Question 8

Why is the liver important?

Tick two answers.

CORRECT ANSWER

it makes bile which breaks down fats
it cleans toxins out of the blood

EDDIE SAYS

The liver is a massively important organ - in fact it has at least twelve major functions. Two of them include the manufacture of bile, which is a mix of digestive chemicals (called ENZYMES) and the removal of toxins, many of which are the remains of the foods once their energy has been released.

ANSWERS

Question 9

Undigested food passes out of the small intestine, into where?

CORRECT ANSWER

into the large intestine

EDDIE SAYS

The large intestine is the final section of the digestive system. It contains several different sections and is initially tasked with absorbing any excess water from the remains of the undigested food that reaches it.

ANSWERS

Question 10

What do you think happens in the large intestine?

Toilet roll

CORRECT ANSWER

undigested food forms feces (poo)

EDDIE SAYS

Once the undigested food reaches your large intestine, there are hardly any nutrients left. However, the large intestine still has an important job to do: it takes any leftover water in the material and re-absorbs it into the body. Any undigested food then becomes hard, because the water has been removed. We call this: faeces/feces (poo). Bacteria in the large intestine also try hard to digest any final nutrients into the body, before we go the toilet and it is too late!