Summary

• Biology is the study of living things.

• There is a defined set of characteristics that something must have to be considered as a living organism:

• Movement – the ability to change position.

• Respiration – the ability to break down food molecules to produce energy.

• Sensitivity – the ability to respond to environmental changes.

• Circulation / Coordination and Control / Cells – the ability to move substances around internally; the ability to regulate the internal environment; the fundamental building block of all living things.

• Growth – the ability to irreversibly increase in size (mass).

• Reproduction – the ability to produce offspring.

• Excretion – the ability to remove waste materials.

• Nutrition – the ability to take in food for energy and growth.

• The characteristics of living things can be remembered using the mnemonic MRSCGREN, where each letter corresponds to the first letter of one of the characteristics.

(Image: sarangib, Pixabay)