TYPES OF CELLS (cellular specialisation)

Here you can watch this video about the different kinds of cells we can find in animals. I hope you enjoy it!

Levels of organisation

Multicellular living things are made up of many different types of cells. These cells work together to same function.

• CELLS: The first level of organization is the cell.

• TISSUES: They are groups of the same type of cells. All cells which form a tissue perform the same function   Example:Animals have muscle tissue which consist of many muscle cells

• ORGANS: Tissues join together to form organs. Tissues in organs work together to perform a common function.   Example: Muscle tissues join together to make the muscle organ.

• SYSTEM: Several organs that perform a function together form a system, such as the digestive system.

• ORGANISM: finally , all the different types of systems work together to form an organism. In a multicellular living thing, cells, tissues, organs and systems all work together so the organism works correctly

THE CELL

The cell

All living things are made of cells. A cell is the smallest unit of life. It is a living thing because it performs the three vital functions: nutrition, interaction and reproduction.

Parts of the cell

Animal cell:

These parts are in both animal and plant cells. Plant cells usually are bigger and have a regular shape, animal cells can be many different shapes.

Cytoplasm: it is inside the cell. It is a viscous liquid and the organelles are in it.

The nucleus: contains the material necessary to reproduce the cell and to control its activities. It is surrounded by a membrane.

The cell membrane: it is the covering around the cell. It takes part in the interaction function.

Organelles: control various functions.

Plant cell:

A part from these, plants have got two more parts.

The cell wall: it is a rigid structure that surrounds the cell membrane and protects the cell.

Chloroplasts: are green organelles that get the light and produce nutrients. Chloroplasts contains chlorophyl.

 Here you can watch this video just to make things clear.

THE SIZE OF LIVING THINGS

The size of living things.

Macroscopic things: they are living things that we can see with the naked eye

 

Microscopic things: also known as microorganisms. They are living things that are so small that we cannot observe them even with a magnifying glass. To look at this living things we need and instrument called microscope.

 Have you ever seen something through the microscope? Let's have a look!

THE THREE VITAL FUNCTIONS OF LIVING THINGS

The characteristics of living things: The three vital functions:

All living things perform specific functions called VITAL FUNCTIONS

Nutrition:  the transformation of food into simple substances called nutrients and how they get energy from them.

Interaction: is the ability to adapt or change the environment or inside the body and to react to them.

Reproduction: when living things produce offspring similar to themselves.

Enjoy this video!