Biology
Organs & organ systems
From a single cell to the whole body: how cells work together and share the work.
What you need first
When you run up a flight of stairs, many parts of your body work at the same time: the heart pumps faster, the lungs take in more air, the muscles move the legs. None of these organs could do it alone. Your body is a huge team in which every part has a job. And this team is built up step by step from tiny cells.
From cell to organ
Many identical cells join together to form a tissue, for example muscle tissue. Several tissues together form an organ, such as the heart or the stomach. An organ is therefore not a single piece, but built from many cells and tissues. In this way, something large and capable is built step by step from the smallest units.
The heart pumps blood through the body, carrying oxygen and nutrients to every cell.
Organs as a team: the organ systems
Organs that fulfil a common task form an organ system. The circulatory system transports blood, the respiratory system brings oxygen into the body and releases , the digestive system breaks down food, the nervous system passes on signals, and the skeleton gives support and protection. This division of labour lets your body handle many things at once without you having to think about it.
Exercises
0 of 6 solvedTime to try it yourself. You can't break anything, every attempt counts.
What forms when many identical cells join together?
Which organ system is responsible for transporting the blood?
Inside the heart there are two atria on top and two ventricles below. How many of these chambers are there in total?
Put the levels of the body's structure in the correct order, from smallest to largest.
- 1organ
- 2tissue
- 3body
- 4cell
- 5organ system
How many lungs does a human have?
Match each organ system to its main task.
Where this leads