The Respiratory and Circulatory Systems

of the Human Body!The Respiratory and Circulatory Systems of the

Human Body are two functions that are very important for our survival! Without them we

would not be alive!

Let’s explore both of these bodily functions and learn

about how and why they are so important!

The Respiratory

System

The Circulatory

System References

The Respiratory SystemBreathing air is necessary for keeping us and many

animals alive. And the two parts that are large and in charge when it comes to breathing are our lungs. Your

lungs are one of the largest organs in your body, and they work with your respiratory system to allow you to take in

fresh air, get rid of stale air, and even talk.

To move on and explore the Respiratory System, you will need to answer a few questions along the way! Here is the

first one…

1. Can we (humans) survive without breathing?

YES NO

INCORRECT!

Humans cannot live without breathing. It is vital for our survival.

Go back and try answering the question again…

X

CORRECT! Humans need to the

breathe in air in order to stay alive!

Let’s move on…

Locate those Lungs!Your lungs are in your chest, and they are so large that they take up most of the space in there. You have two lungs, but they aren't the same size the way your eyes or nostrils are. Instead, the lung on the left side of your body is a bit smaller than the

lung on the right. This extra space on the left leaves room for your heart.

2. Are human lungs the same size?

The lungs in the human body are not the same size. Remember the right lung us bigger than the left lung because it needs to leave room for the heart. Go back

and try answering the question again…

The left lung is smaller than the right lung to

allow room for the heart.

A look inside in Lungs!From the outside, lungs are pink and a bit squishy, like a

sponge. But the inside contains the real lowdown on the lungs! At the bottom of the trachea (say: TRAY-kee-uh), or windpipe,

there are two large tubes. These tubes are called the main stem bronchi (say: BRONG-kye), and one heads left into the

left lung, while the other heads right into the right lung.

3. At the Bottom of the Trachea what are the two large tubes called?

Bronchi Stems

Windpipe

The two main tubes that lead into the lung under the trachea are

called Bronchi stems.

The trachea is also known as the windpipe, therefore that is not the name of the tubes

leading into the lungs. Go back and try answering the question again…

As you breathe in, your diaphragm contracts and flattens out. This allows it to move down, so your

lungs have more room to grow larger as they fill up with air. "Move over, diaphragm, I'm filling up!" is

what your lungs would say. And the diaphragm isn't the only part that gives your lungs the room

they need. Your rib muscles also lift the ribs up and outward to give the lungs more space.

4. Apart from the diaphragm, what else allows the lungs to expand?

All about Inhaling

Trachea Ribs

The trachea does not move to allow more space for the lung to expand. Go back and

try answering the question again…

Yes your rib muscles lift the ribs up and outward to give the

lungs more space to expand.

When it's time to exhale (breathe out), everything happens in reverse: Now it's the diaphragm's turn to say, "Move it!" Your diaphragm relaxes and moves up, pushing air out of the lungs. Your rib muscles

become relaxed, and your ribs move in again, creating a smaller space in your chest.

5. When you exhale, what pushes air out of the lungs?

Waiting to Exhale

Diaphragm

Rib muscles

Yes, the diaphragm relaxes and moves up, pushing air out of the lungs when you

exhale!

The rib muscles become relaxed, and your ribs move in again, creating a smaller space in your chest, so this isn’t what pushes the air out of your lungs. Go

back and try answering the question again…

So there you have it! The Respiratory System is an important function to help us breathe in oxygen

and keep us alive! Located in our chest, lungs are pink and squishy like a sponge. As you breathe in air (inhale) your lungs fill up and expand but when you exhale, the diaphragm moves up and pushes

the air from your body. Breathing is very important survival so we need to say thank you to

our lungs!

Now that we have finished the Respiratory System, press the

home button to explore the Circulatory system.

The heart and circulatory system (also called the cardiovascular system) make up the network that delivers blood to the body's tissues. With each heartbeat, blood is sent throughout our bodies, carrying oxygen and nutrients

to all of our cells.

To move on and explore the Circulatory System, you will need to answer a few questions along the way! Here is

the first one…

1. What is another name for the circulatory system?

The Circulatory System

Cardiovascular System

Respiratory System

Yes! The other name for the Circulatory System is called the cardiovascular

system!

Although it has functions to do with the Circulatory System, the Respiratory

System is not the other name. Go back and try answering the question again…

The circulatory system is composed of the heart and blood vessels, including arteries, veins, and capillaries. Our bodies actually have two circulatory systems: The pulmonary circulation is a short loop

from the heart to the lungs and back again, and the systemic circulation (the system we usually think of as our circulatory system)

sends blood from the heart to all the other parts of our bodies and back again.

2. Fill in the gaps: The _________ ______ is composed of the heart and Blood Vessels.

Circulatory System

Arteries and veins

The Circulatory System is composed of not only the heart

and blood vessels, but also arteries, veins and capillaries.

Unfortunately that is not the answer because arteries and veins are also composed of the

Circulatory System. Go back and try answering the question again…

The heart is the key organ in the circulatory system. As a hollow, muscular pump, its main function is to propel blood throughout the body. The heart has four chambers that are enclosed by thick, muscular walls. It lies between the lungs

and just to the left of the middle of the chest cavity. The bottom part of the heart is divided into two chambers called

the right and left ventricles, which pump blood out of the heart.

3. What are the chambers called that pump blood out of the heart?

The Heart of the Body

Muscular Walls

Right & Left Ventricles

Muscular walls are in fact what enclose the heart and keep it safe.

Go back and try answering the question again.

Well done! The right and left ventricles pump blood out of

the heart to other parts of the body.

Blood vessels carrying blood away from the heart are called arteries. They are the thickest blood vessels, with muscular walls that contract to keep the blood moving away from the heart and through the body. In the systemic circulation, oxygen-rich blood is pumped from the heart into the aorta. This huge artery curves up and back from the left ventricle, then heads down in front of

the spinal column into the abdomen. Two coronary arteries branch off at the beginning of the aorta and divide into a

network of smaller arteries that provide oxygen and nourishment to the muscles of the heart.

4. What are the thickest blood vessels?

The Role of Blood Vessels

Arteries Aorta

Arteries are the thickest blood vessels which carry blood away

from the heart to around the body.

The aorta is the area of the heart where oxygen-rich blood is pumped into. Go back and try answering the

question again…

Purpose of the Circulatory System

The circulatory system works closely with other systems in our bodies. It supplies oxygen and nutrients to our bodies by working with the respiratory system. At the same time,

the circulatory system helps carry waste and carbon dioxide out of the body. Hormones — produced by the endocrine system — are also transported through the blood in our circulatory system. The body's chemical messengers and hormones transfer information and

instructions from one set of cells to another.

5. What other system does the Circulatory System work with?

Cardiovascular System

Respiratory System

Remember the cardiovascular system is another name for the Circulatory system. Go back and try answering the question

again…

Yes! The Respiratory System works closely with the Circulatory system. It supplies oxygen and nutrients to

the body.

Now that we have finished the Circulatory System, press the home button to explore the

Respiratory system.

The circulatory system is composed of the heart and blood vessels, including arteries, veins, and capillaries.

As a hollow, muscular pump, the heart’s main function is to propel blood throughout the body. Blood vessels

carrying blood away from the heart are called arteries. They are the thickest blood vessels. The circulatory

system supplies oxygen and nutrients to our bodies by working with the respiratory system

ReferencesKids Health. (2013). Heart and Circulatory system. Retrieved from: http://kidshealth.org/teen/your_body/body_basics/heart.html#

Kids Health. (2013). Your Lungs and Respiratory system. Retrieved from: http://kidshealth.org/kid/htbw/lungs.html