Digestive System Analogies

The mouth's two main functions are

to mash up and chew the food that is

put into it (to eat), and to secrete saliva

from salivary glands.

An analogy for the mouth could be a garbage disposal. The garbage disposal is like a mouth

because it mashes up the waste and then sends

it down the pipes in the same way the mouth chews the food and then pushes it down the throat with help from the tongue.

An analogy for the secretion of saliva

in the mouth could be a washing machine.

The soap in the washing machine is like the

saliva because the soap starts to break down the dirt in the clothing in the same way the saliva has

certain enzymes that start to break up the

carbohydrates in the mouth.

The epiglottis is a flap of

skin that covers the trachea (windpipe) and does not allow food to go down it (when food does go into the trachea it is called choking).

An analogy for the epiglottis

is a toilet cover. A toilet cover is like the epiglottis because it prevents objects that could harm the toilet from going into it in the same way the epiglottis prevents food from going into the trachea.

Toilet cover (epiglottis)

The esophagus is a tube that

connects the mouth to the stomach.

This tube is where food is meant to

go down as opposed to your trachea,

nasal passage, or out of your mouth.

An analogy for the esophagus

could be a water slide. A water slides is like

the esophagus because its purpose is to get the rider from the top of the slide to the bottom in the same way the esophagus gets the chewed food or bolus from the mouth to the stomach.

Start point (mouth)

Rider of the slide (bolus)

End point (Stomach)

The stomach has three main functions.

One of them is to mix bolus into smaller pieces.

This function of the stomach is like a blender because the blender makes whatever you put into it smaller than it originally was in the same way the stomach churns bolus until it breaks down into smaller pieces.

Food is mixed into pieces

that are smaller than the original

whole food.

The second function of the stomach is

to mix the, now smaller, pieces of bolus with gastric acid (hydrochloric acid mixed with pepsin). An analogy for that could be a mixer. The second function of the stomach is like a mixer because it mixes all the ingredients that are put into it together in the same way the stomach mixes together the pieces of bolus with the gastric acid.

Whisk that is attached to the mixer. The whisk combines the food together (stomach which puts together the bolus with gastric acid)

Food that is going to be mixed together

(bolus that is going to be churned by

stomach)

The final function of the stomach is to

store swallowed food and liquid food until it is ready to be used. This can be compared to a refrigerator because a refrigerator stores leftover food until it is going to be eaten as a meal. Like the stomach, a refrigerator can keep food in it until the moment it is needed.

Refrigerator (stomach)

Food (bolus)

Like the stomach, the small intestines

have multiple functions. One of the

functions of the small intestines is to

absorb nutrients into the blood stream.

An analogy for the absorption occurring

in the small intestines could be a sponge.

A sponge is like the small intestines because it soaks up the nutrients in the same way the small intestines absorb the nutrients into the blood stream.

Sponge (small

intestine)

Hole in sponge (capillary)

The other function of the small intestine is to

finish digesting the partially digested carbohydrates and proteins, and to fully digest fats/lipids. An analogy for the digestion portion of the small intestine could be 409 cleaning spray. 409 is like the small intestines because it finishes the job of getting rid of the final grease stuck on pans or ovens in the kitchen in the same way the small intestines finish digesting all the final proteins, lipids, and carbohydrates that are still left to digest.

409 cleaning (digestion

that occurs in small intestines)

The large intestines have two main functions.

One of the functions is to send waste to the rectum to be stored until elimination through the anus. An analogy for that could be a sewage pipe. A sewage pipe is like the large intestine because it takes the waste into the sewer system until it is disposed of elsewhere.

Another function of the

large intestine is to absorb

water and certain vitamins and minerals.

An analogy for the absorption occurring

in the large intestine could be a washcloth.

A washcloth is like the large intestine because

it can be used to clean up water and crumbs in the same way the large intestine absorbs water from undigested food and some vitamins and minerals.

Washcloth (large intestine)

The main function of the rectum is

to store and compact waste until it is ready to be

eliminated through the anus.

An analogy for the rectum could

be the giant candy containers that have a

handle at the end which allows the candy to fall

(I don't know what they are called.) The candy dispenser is like the rectum because it stores

the candy until the handle is pulled and the candy falls out, in the same way the rectum stores the waste until it is ready to be eliminated and the sphincter then relaxes and the waste goes out through the anus.

M&M's (waste)

Handle (sphincter)

Part where M&M

come out (anus)

M&M released (elimination of waste)

The liver is the largest organ in the body and functions to make bile that breaks up fat and filters the blood

One analogy for the liver is an oil filter because it filters waste and chemicals from the blood

another analogy for the Liver is that it acts a chemical factory, making bile use to dissolve fat

The gall bladder stores bile, a substance that breaks up fat, and squirts it into the small intestine when food passes through

an analogy for the gall bladder is a fireboat

that sprays water when needed similar to how

the gall bladder sprays bile onto the food

The pancreas is an enzyme-producing gland located below the stomach and above the intestines. Enzymes from the pancreas help in the digestion of carbohydrates, fats and proteins in the small intestine.

The anus is a muscular opening

at the end of the rectum (large intestine)

and functions to control the release of feces

Analogies

Teeth

Tongue

An analogy for the secretion

Toilet (trachea)

The pancreas is also like a chemical

factory because it produced digestive enzymes

(chemicals) that help break down food

Large Intestine

Appendix

Anus

The anus is like a sewer discharge pipe eliminating waste products