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respiration and breathing

OLogy Series
biology
card
213

respiration and breathing

OLogy Series
biology

Most living things need oxygen to survive. Oxygen helps organisms grow, reproduce, and turn food into energy. Humans get the oxygen they need by breathing through their nose and mouth into their lungs. Oxygen gives our cells the ability to break down food in order to get the energy we need to survive. Although other animals may use different organs to breathe with, they all get oxygen into their bodies through respiration.

One organism that does not need oxygen to survive is:

big foot

a butterfly

the bacterium Clostridium botulinum

Are you right?

Correct!

Clostridium botulinum is a really tough bacterium! This bacterium produces the botulism toxin, which attacks the nerves of humans who ingest it. It can live in food that has been sealed in air-tight containers. This toxic bacterium makes people very sick when they eat food contaminated with it.

Fish extract oxygen from water using:

gills

lungs

mouths

Are you right?

Correct!

Fish need oxygen to breathe just like we do. They get their oxygen from the water using gills, which are located behind their eyes. Water enters a fish’s mouth and then passes over its gills, which absorb the oxygen in the water and circulate it to all the cells in the fish’s body.

Water contains NO oxygen at all.

Fact
or
Fiction
?

Fiction

Water contains oxygen just as air does. One water molecule is made up of two hydrogen atoms and one oxygen atom. That's why we call water H2O.

Over 2.3 billion years ago, the air surrounding the Earth contained no oxygen at all.

Fact
or
Fiction
?

Fact

Over 2.3 billion years ago, the oceans back then contained very simple forms of life, such as single-celled bacteria, that didn’t need oxygen to live!

Term: respiration and breathing
Definition: the process by which oxygen is taken in and distributed throughout the body of a living thing
Organs of respiration for various animals: gills, lungs, pores, and cell walls
Why it is important to life: provides organisms with oxygen, which is used to extract and break down the energy in food

Image credits: Eric Hamilton.