CHARACTERISTICS OF LIVING THINGS WHAT ARE THE CHARACTERISTICS

CHARACTERISTICS OF LIVING THINGS WHAT ARE THE CHARACTERISTICS OF ALL LIVING THINGS?

6 CHARACTERISTICS OF ORGANISMS 1. Cellular organization • Unicellular – single celled such as a bacteria • All body functions take place within one cell • Multicellular – composed of many cells • Cells can be specialized for different functions (such as muscle cells for movement, blood cells to deliver O 2)

2. Similar Chemistry • • • Nucleic Acid (DNA) Water (most abundant) Carbohydrates (energy source) Protein (structure & communication) Lipids (energy & structure) ATP (energy cells can use)

3. Use Energy • Organisms get energy from taking in & breaking down materials • Metabolism – the combination of chemical reactions by which an organism builds up or breaks down materials • Organisms use energy to grow, replace cells, repair injury 4. Response to Surroundings • Stimulus – a change that causes an • organism to react • Ex. Light, sound, etc. • Response – an action or change in • behavior • Ex. A plant growing toward a light source

5. Grow & Develop • Growth = getting larger • Development = process of change that occurs during an organism’s life (ex. tadpole turning into a frog) 6. Reproduction • Production of offspring that are similar to the parent(s) • Asexual – one parent produces offspring identical to the parent • Sexual – two parents produce offspring with a combination of the parents genetic information

WHERE DO LIVING THINGS COME FROM? • Living things only arise from other living things through reproduction. • 400 years ago people believed in spontaneous generation, the mistaken idea that living things could arise from nonliving sources. • 2 scientists helped to disprove the idea of spontaneous generation: 1. Redi designed an experiment using decaying meat and flies. 2. Pasteur designed an experiment using broth and bacteria.