* Organization: Trees are made of cells, which are organized into tissues, organs, and organ systems.
* Metabolism: Trees carry out chemical reactions to obtain and use energy, build structures, and remove waste. They photosynthesize to make their own food, and they respire to release energy.
* Growth: Trees increase in size and complexity over time.
* Adaptation: Trees have evolved to survive in a variety of environments. They can adapt to changes in temperature, rainfall, and soil conditions.
* Response to Stimuli: Trees can respond to changes in their environment, such as light, temperature, and water availability. They can also respond to touch and gravity.
* Reproduction: Trees reproduce sexually, producing seeds that grow into new trees. They can also reproduce asexually, through processes like sprouting from roots or branches.
In short, trees are alive because they have the ability to grow, reproduce, adapt, and interact with their environment, just like any other living organism.
