Specialisation of eukaryotic cells

In a complex multicellular organism, different cells perform different functions. A specialised cell has features that help it carry out a particular role. These features may include its shape, the abundance of a cell structure, or the way structures are arranged.

For example, a root hair cell absorbs water from the soil. Its long, thin extension gives it a large surface area in contact with the soil, allowing more water to enter the cell.

A sperm cell has a tail that propels it towards an egg. It also has many mitochondria, which release energy needed for the tail to move. Both features are suited to the sperm cell’s role in reaching the egg.

To explain a cell’s adaptation, name a specific feature and link it to the function it helps the cell perform. For a root hair cell, stating that it has a long extension identifies the feature; explaining that the extension increases the surface area for water absorption shows how the feature helps.

Cell differentiation

As an organism develops, its cells become specialised for different jobs. This process is called cell differentiation. It produces different cell types that can carry out different roles in the organism.

During differentiation, a cell acquires sub-cellular structures suited to its function. For example, a sperm cell develops a tail that allows it to swim towards an egg cell. It also contains many mitochondria, which release energy for movement.

Differentiation in animals and plants

Most types of animal cell differentiate at an early stage of development. In mature animals, cell division is mainly restricted to repairing tissues and replacing cells.

Many types of plant cell, by contrast, retain the ability to differentiate throughout the plant’s life.