Biology Unit 1: Breathing and respiration chapter 1.1, 1.2

• Biologie
• Middelbare school
• vwo
• Leerjaar 2,3

unit 1: Breathing and respiration part 1

What are you going to do today?

at the end of this lessonUp you can:

* name the functions of the respiratory system

* describe combustion and respiration including the terms fuel, oxygen, water, carbon dioxide and energy

* describe the differences in oxygen and carbon dioxides levels in inhaled and exhaled air.

* describe respiration in organisms and explain the relationship with physical activity using the terms glucose, oxygen, water, carbon dioxide, energy 

Why is the respiratory system important?

Your respiratory system is the network of organs and tissues that help you breathe. 

This system helps your body absorb oxygen from the air to create energy for our body.

It also cleans waste gases from your blood and protects you from things that can irritate you body. 

It also helps us smell and make sound. 

Combustion

Combustion is another name for burning.

In a combustion reaction, a fuel is burned and it reacts with oxygen (gas) to release energy.

Take for example the candle. 

The wax is the fuel. Burning the fuel (you need Oxygen for this) creates energy which is released in the form of heat and light.

When the fuel is burned, it disappears and other substances appear in its place. 

The substances produced by combustion are called combustion products. Sometimes also referred to as waste products (afvalstoffen).

Look at the candle again. You can see two black arrows going away from the flame. The arrows stand for the combustion products, in this case: Carbon dioxide (gas) + steam (water).

The fire triangle summarises the three things needed for combustion - a fuel, heat and oxygen. If one of these things is removed from a fire, the fire goes out.

1) What does combustion mean?
2) What does it do?

1. 1) Burning, 2) create energy
2. 1) Burning, 2) create Oxygen
3. 1)Heat, 2) create energy
4. 1) Energy, 2) create Carbon dioxide

Make the formula of combustion in the candle.

Carbon Dioxide

Water

Oxygen

Energy

Fuel

Explain what combustion products are

What are the combustion products of the combustion of a candle?

1. Carbon dioxide and Oxygen
2. Oxygen and steam
3. Steam and Carbon dioxide
4. Carbon dioxide and energy

Soooo... what exactly does this have to do with our respiratory system?

At this point you know:

• What combustion is and how it creates energy,

• What combustion products are,

• What an indicator is.
  

(if you at this point do know know any of the above, 

read the slides again!)

The next slides will show you how combustion and our 

respiratory system are connected!

Respiration

A kind of combustion also happens in your body. The combustion in your body goes much slower than in a candle and it does not use fire. 

This combustion - called respiration - takes place in every single cell in your body. 

This goes on day and night, it never stops. Without respiration a cell dies.

Respiration happens in every living cell in every living organism.

Energy

Our body uses a lot of energy to:

•  Keep our body temperature at 37 degrees, 
•  to move, 
•  to grow, 
•  to keep our organs working etc. 

Respiration creates the energy we need to do the above. 

How does respiration work?

Respiration needs fuel.

The most commonly used fuel is glucose. This is a sugar. 

You have learned that plants make glucose and Oxygen by photosynthesis.

Humans and other animals eat those plants. That is how we get the glucose in our bodies and we take the Oxygen from the air. 

Make the formula of Photosynthesis

Glucose

Carbon Dioxide

Water

Oxygen

Sunlight

What happens during respiration?

Respiration can happen when we have Glucose (fuel)

and Oxygen. 

When breath out, you are getting rid of Carbon dioxide. 

You also lose some water when you exhale.

--> waste products.

Respiration produces the energy we need.

Cell respiration

Glucose

Oxygen

Energy

Carbon dioxide

Water

Respiration during exercise

During exercise there is an increase in physical activity and muscle cells respire more than they do when the body is at rest.

The heart rate increases during exercise. The rate and depth of breathing increases - this makes sure that more oxygen is absorbed into the blood, and more carbon dioxide is removed from it.

Make the right formula of respiration

Oxygen

Energy

Water

Glucose

Carbon Dioxide

What are the waste products of respiration

1. Carbon Dioxide + Oxygen
2. Oxygen + Water
3. Water + Energy
4. Carbon Dioxide + water

What is the fuel for respiration?

1. Carbon Dioxide
2. Oxygen
3. Glucose
4. Energy

Respiration only happens in humans

1. True
2. False

Respiration only happens during the day

1. True
2. False

Without respiration we would die

1. True
2. False

respiration and breathing are the same thing?

1. True
2. False

The composition of the air we breath

Air is a mixture of several gasses but it consists mainly of Nitrogen (stikstof) and Oxygen. 

Air always contains a bit of water vapor, although the amount of water varies. The composition is therefor often stated for dry air.

Difference in air composition while breathing in and out

Inhaled air contains:

• more oxygen used to create energy.
  
• less carbon dioxide than exhaled air.
  

Exhaled air contains:

• more carbon dioxide produced as a waste product of energy production.
  
• less oxygen as it has been used in respiration.
  

Gas	% in inhaled air	% in exhaled air
Oxygen	21	16
Carbon Dioxide	0.04	4
Nitrogen	79	79

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Well done!

homework 

read and learn 1.1 and 1.2 

 do exc. 1.1 4 to 8

1.2  4 to 8