We are all life scientists!

What are the Characteristics of Life? Chapter 1 What is Life? Key Questions: What are the Characteristics of Life? What do living things need to survive?

What are the Characteristics of Life? Chapter 1 What is Life? What are the Characteristics of Life? All living things share six characteristics in combination.

These are human cheek cells. What kind of organism are you? They are made of cells! An organism can be made of one single cell – unicellular. Or many cells as the building blocks of a larger organism – multicellular. Human cheek cells 400x

Cells are made of other chemicals! Proteins Carbohydrates Lipids Nucleic Acids Water These compounds make up all known life.

Living things respond to surroundings. Stimulus - a reaction to a change Response – an action or behavior

Living things respond to surroundings. Chapter 1 What is Life? Living things respond to surroundings. Adaptation - an inherited behavior or characteristic that enables an organism to survive & reproduce. This type of response takes a long time and many generations. Over time, adaptations are modified by natural selection.

Life is always changing….. On the level of DNA…… Change = Evolution Chapter 1 What is Life? Life is always changing….. On the level of DNA…… Change = Evolution

Living things grow and develop. Grow = larger Develop = more complex

Living organisms reproduce. 2 types: Sexual reproduction Asexual reproduction

What do living things need to survive? Water Food Autotroph/heterotroph Living space Stable internal conditions – homeostasis

Test Yourself on these questions… A Short Quiz: 1. What are the six characteristics of life? 2. What is homeostasis? What is an example of homeostasis? 3. Is a computer living? Why or why not? 4. Why is energy required by living things?

6 characteristics of life They are made of one or more cells They use energy (acquire or make food) They respond to the environment They grow and develop They reproduce They respire (breathe) or move or excrete waste

Homework Make a checklist of five living and five nonliving examples. Provide a key for the checklist, including an explanation of why the examples are living or non living.