It’s Alive!!! What all living things have in common. What is an organism? Organism= anything that has or once had all of the characteristics which define life

All living things have 9 basic characteristics in common.

1. DNA (genetic code) Offspring inherit their traits from their parents. These traits are passed on using DNA.

2. Organization Multicellular - many cells (example: plant) these cells are made up of organelles, which ae made up of molecules, which are made up of atoms. Single-celled – one cell (example: bacteria) these cells are made up of organelles, which ae made up of molecules, which are made up of atoms.

The levels of biological organization from smallest to largest are: Atom < Molecule < Cell < Tissue < Organ < Organ System < Organism

3. Growth and Development Most unicellular organism only grow, or increase in size. Multicellular organisms grow and develop (cells continue to divide in order to mature).

Grows and Development Most organisms begin as one cell! Growth = results in the addition of mass to an organism, and in many organisms, the formation of new cells and new structures Development = the process of natural changes that take place during the life of an organism

4. Stimulus Response Detection and response to stimuli (both internal and external).

Stimulus Response Stimulus = anything that is part of either an organism’s external or an organism’s internal environment that causes a reaction Response = an organism’s reaction to a stimulus

5. Reproduction All organisms produce new organisms through reproduction. Sexual reproduction – two cells from different parents unite to produce the new organism that are non- identical to the parents. Asexual reproduction – new organism has a single parent and produces identical offspring.

6. Energy Acquisition and Release One view of life is that it is a struggle to acquire energy (from sunlight, inorganic chemicals, or another organism), and release it.

Energy Acquisition and Release Autotrophs = plants organisms that produce their own energy using light from the sun through photosynthesis. Heterotrophs = animals organisms that get their energy requirements by consuming other organisms

7. Adaptation The characteristics of populations change over time, usually in response to their environment. Charles Darwin began the recognition of the marvelous adaptations all life has that allow those organisms to exist in their environment.

8. Cells All living things are made of cells. Unicellular – only one cell Multicellular – two or more cells

9. Homeostasis Homeostasis is the maintenance of a constant internal environment in terms of temperature, pH, water concentrations,etc.

Remember... DOG’S REACH