Organ Systems

What is a cell?

The basic unit of life.

What is a tissue?

A group of similar cells working together to perform a function.

What is an organ?

A group of tissues working together to perform a specific job.

What is an organ system?

A group of organs working together to carry out a major body function.

What is the hierarchy of biological organisation?

Cell → Tissue → Organ → Organ system.

What is the function of a sperm cell?

Carries DNA to the egg for fertilisation and has a tail for swimming.

What is the function of a root hair cell?

Absorbs water and nutrients with a large surface area.

Why are bacteria unicellular?

They are made of just one cell.

Why don’t bacteria need a circulatory system?

They are small and substances diffuse directly in and out of the cell.

Why do multicellular organisms need a circulatory system?

They need a transport system to move substances efficiently around the body.

What is an example of a cell?

Sperm cell or root hair cell.

What is an example of a tissue?

Muscle tissue.

What is an example of an organ?

Heart.

What is an example of an organ system?

Circulatory system.

What does a group of similar cells form?

A tissue.

What does a group of tissues form?

An organ.

What does a group of organs form?

An organ system.

What is the function of the breathing system?

Takes in oxygen and removes carbon dioxide.

What is the function of the circulatory system?

Transports blood around the body.

What is the function of the excretory system?

Removes waste substances from the body.

What is the function of the digestive system?

Breaks down food into small usable molecules.