Chapter 2: It’s Alive!! Or Is it?? DO NOW: READ PAGE 34 IN YOUR TEXTBOOK

How are living things alike? Even though an amazing variety of living things exist on Earth, they are all alike in several ways. We will study the six common characteristics of all living things, along with the four basic needs of all living things.

6 Characteristics of All Living Things 1. LIVING THINGS HAVE CELLS A CELL is a membrane covered structure that contains all of the materials necessary for life  Some organisms are single celled organisms, made up of only one cell  Some organisms are made up of trillions of cells.

2. Living Things Sense and Respond to Change. A change in an organism’s environment that affects the activity of the organism is called a STIMULUS  A stimulus can be chemicals, gravity, darkness, light, sounds, tastes, or anything that causes an organism to respond in some way. HOMEOSTASIS – is the maintenance of a stable internal environment.  Even though the external environment may change, we must maintain a stable internal environment

3. Living Things Reproduce. Organisms make other organisms like themselves Either by ASEXUAL REPRODUCTION – where a single parent produces offspring that are identical to the parent Or by SEXUAL REPRODUCTION – two parents produce offspring that share characteristics of both parents

4. Living Things Have DNA deoxyribonucleic acid The cells of all living things contain DNA DNA provides instructions for making molecules called proteins Proteins take part in almost all of the activities of an organism’s cells HEREDITY – the transmission of characteristics from one generation to the next

5. Living Things Use Energy Metabolism – an organisms metabolism is the total of all the chemical activities that it perfoms.

6. Living Things Grow and Develop

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