Enzymes & Digestion - Cell Organisation (GCSE Biology)

Cell Organisation

The Building Blocks of the Body

The human body is made up of many cells, tissues, organs, and organ systems. You need to understand how each one links to the next.

Cells

• All living things are made from cells. Each living organism is made from many cells being put together. Cells are the basic building blocks of all living organisms.
• Cells are specialised and differentiated. Cells in different tissues are differentiated and adapted to their specific function. For example, in ‘1.1.3 Cell Specialisation’, we learnt about the variation between sperm, nerve, and muscles cells in the human body.

Tissues

• Tissues are made from similar cells. Many of the same type of specialised cell, with similar structures and functions, all come together to form a tissue. For example, many cardiac cells would make up cardiac tissue and they work together to contract and push blood out of the heart.

Organs

• Organs are made from tissues. Many different types of tissues, each with their own specific function, come together to make an organ. For example, the heart is an organ, and is made from muscular, epithelial, nervous and connective tissue.

Organs Systems

• Organs systems are made up of different organs. Different organs are grouped to perform a function. For example, the heart and blood vessels are two organs which make up the circulatory system. The circulatory tract pumps blood around the body and carries oxygen to organs (via blood). Another organ system is the respiratory system, which includes the nose, trachea, larynx, pharynx, lungs, bronchi and alveoli.

• The human body has many organ systems. The body has several organ systems, including the cardiovascular, muscular, nervous, skeletal, digestive, lymphatic, urinary and respiratory systems.