1. Energy: All organisms need a source of energy to power their life processes. This energy comes from food. Plants get energy from sunlight through photosynthesis, while animals get it by eating plants or other animals.

2. Water: Water is essential for all life. It makes up a large portion of an organism's body and is involved in many important processes, such as transporting nutrients, regulating temperature, and removing waste products.

3. Suitable environment: Organisms need a suitable environment that provides the right conditions for them to thrive. This includes things like temperature, humidity, and the availability of resources like food and shelter.

These are just three of the many things that organisms need to survive. Other important factors include oxygen for most organisms, appropriate light levels, and the ability to reproduce.