Specialised animal cells

There are many different types of cells in animals. Each type is specialised to do a particular role. These ensure that the organism functions as a whole.

Type of animal cell

How it is adapted to carry out its function

Sperm

Diagram of a sperm cell

The head contains the genetic material for fertilisation in a haploid nucleus. The acrosome in the head contains enzymes so that a sperm can penetrate an egg. The middle piece is packed with mitochondria to release energy needed to swim and fertilise the egg. The tail enables the sperm to swim. Sperm are the smallest cells in the body and millions of them are made.

Egg cell

Cell diagram showing the membrane, cytoplasm, mitochondria and haploid nucleus

The cytoplasm contains nutrients for the growth of the early embryo. The haploid nucleus contains the genetic material for fertilisation. The cell membrane changes after fertilisation by a single sperm so that no more sperm can enter. Eggs are one of the biggest cells in the body and only a few are made.

Ciliated epithelial cell

Diagram showing how cilia move particles

Cilia on the surface beat to move fluids and particles up the trachea.