Chapter 1: Living Things Aim: What is the difference between living and nonliving things?

Characteristics of Living Things Any living thing is called an organism Vary in size Have different behaviors and needs 1. Made up of small units called cells Some organisms are one celled Some are many celled Each cell contains heredity material and has a structure

2. Interact with their surroundings Responds to stimuli Homeostasis-organisms ability to keep the proper conditions inside no matter what is going outside the body 3. Use energy Comes directly or indirectly from the Sun-is the source of all energy 4. Grow and develop All organisms have a life span

Nonliving Things 5. Reproduce Don’t have these characteristics Don’t need things in order to survive Examples: Water Air Rocks Clouds

Aim: What are the basic needs of all living things? Place to live Some need a hot environment Some need a cold environment Some live in the ocean Few live on the bottom of the ocean Organisms surroundings must provide for all of its needs

2. Raw Materials all living things need water Most organisms made up of 50 % H2O Humans made up of 60-70% H2O Need proteins, fats and sugars

Aim: How do we classify living things?

Classification Early classifications included grouping plants depending on how they were used and animals on human traits, such as courageous Aristotle classified living things by how they looked Example: Animal categories included hair or no hair, four legs or two legs

Modern classification Carolus Linnaeus came up with a new system of classification based on the structure of the organism Modern classification Includes Linnaeus’ system Similarities of internal and external factors study fossils, hereditary information and early stages of development Scientists use all of this information to find and organisms phylogeny

Today’s Classification System Organisms are grouped into six kingdoms Kingdom is the first and largest category Organisms are placed into these kingdoms based on various characteristics Smallest classification is a species Organisms that belong to the same species can mate and reproduce

Aim: How do scientists name organisms?

Binomial Nomenclature Two-word naming system used by Linnaeus Used by modern scientists First word identifies the genus of the species Second words tells you something about the organism-what it looks like, lives or who discovered it Examples: Red Maple Tree=Acer Rubrum

Using Scientific Names Used for four reasons: Help avoid mistakes Organisms with similar evolutionary history are classified together in the same genus Give descriptive information Allows information about organisms to be organized easily and efficiently

Aim: How do you use a dichotomus key?

Tools for Identifying Organisms Field guides Have descriptions and illustrations of organisms Information about where they live Can identify species from around the world

Dichotomous keys Detailed list identifying characteristics that includes scientific names Arranged in steps Can identify and name species