Living organisms share characteristics such as the ability to move and reproduce. There are different types of living organisms including plants, animals, fungi, or bacteria.
Living organisms have the following characteristics in common:
- Movement- they can move or change their position without outside help.
- Reproduction– they can make more of the same kind of organism as themselves.
- Interaction– they can detect or sense stimuli and respond to them. For example, green plants grow to sunshine, or human beings blink when the sun shines into the eyes.
- Growth- they can permanently increase their size or mass by increasing the number or size of their cells.
- Respiration– oxygen is taken up into the animals' lungs, pass down into the bloodstream, then to the rest of the organs. Finally carbon dioxide (waste gas) is taken out.
- Excretion– they can excrete toxic materials, waste products of metabolism, and excess substances (note that excretion is not the same as egestion).
- Nutrition- they can take in and absorb nutrients such as organic substances (proteins, vitamins, carbohydrates...) and minerals. These nutrients contain the energy needed for growth and tissue repair.