TISSUeS ForM orGaNS

Refresh What is the biggest organ in a human being?

8 What are organs?

Organs are formed of a combination of different tissues. Organs perform a particular function. There are internal and external organs, depending on whether they are visible on the outside of the body or located inside the living organism.

Each organ has got a specific task to perform. For example, the heart is an organ that pumps blood around the human body. Other organs, such as the stomach, play a role in nutrition and digestion. Many organs are protected by bones.

1 Classify these human organs as external organs or internal organs in your notebook.

a) The brain c) The skin e) The mouth g) The heart

2 Match the sentence halves in your notebook.

1. The heart is an organ which….

2. In the stomach, ….

3. The brain is the organ which… b) The nose d) The kidneys f) The ears h) The lungs a) controls the nervous system. b) pumps blood. c) there would be no movement. d) food is digested and processed.

4. Without the muscles, ….

9 Types of organs

Depending on the type of living organism, organs can have different sizes, shapes and functions. Plants and animals haven’t got the same organs because they perform living functions in different ways. Plants get their energy from the process of photosynthesis, for example, but animals obtain energy by digesting food.

Animal organs

The major organs in animals are the brain, heart, lungs, kidneys, liver, stomach, intestines, skin and reproductive organs. They have got a specific function.

Plant organs

The main organs in plants are the leaves, roots, stem and reproductive organs. Like with animal organs, plant organs have got a specific function.

3 Make a word cloud with the names of all the organs that appear in this section and any others that you know. Use green to write the names of plant organs and red for animal organs.

• Write the animal and plant organs next to the function they perform in your notebook. Some may perform more than one function. Can you add more organs to each function?

Lungs Stomach a) Obtain oxygen b) Obtain nutrients

Kidneys Ear

Intestines Root

Flower Leaves Ovaries c) Create new living organisms d) Receive external information e) Eliminate waste