Introduction to Living Things1.2, 1.3, 1.4

Organism•Any living thing

⚫Bacteria⚫Animals⚫Fungi⚫Plants⚫Etc

Characteristics of L.T.•In order to be considered alive, organisms must have these 5 characteristics:⚫Living things are organized⚫Living things respond to stimuli⚫Living things use energy⚫Living Things grow and develop⚫Living things reproduce

Living things are organized•Every living thing is made up of one or more cells.⚫Cells=the basic unit of life⚫Cells contain the hereditary material, called DNA

Living things respond to stimuli•Stimulus=something that causes a change in an organism

•Response= the reaction to the stimulus

•Homeostasis= an organisms ability to keep proper conditions inside, no matter what is going on outside

Living things use energy•Plants, and some bacteria get energy from the sun

•Animals get energy from food

Living things grow and develop• Growth=organism gets bigger

• Development=Changes that take place during the lifetime

• Lifespan= How long an organism is expected to live

Living things reproduce•Reproduction=making babies

Living things have 2 needs1. A place to live (habitat)

1. Must be a place that suits the needs of the organism

What else?2. Raw materials

•ALL organisms need water to survive

•Humans also need ⚫Food ⚫Oxygen

•Plants also need ⚫Sunlight ⚫Carbon dioxide (plants do not need oxygen!)

Where does life come from?•Living things only come from other living things⚫This is called biogenesis

How are living things classified?

Carolus Linneaus•Born Carl Linne in 1707

•Looked for a way to classify organisms⚫Based his classification on how organisms looked

⚫Example: All trees together, all bear-looking creatures together, all fish together, etc.

•Developed Binomial Nomenclature⚫2 word naming system still used today.

Binomial Nomenclature

•2 word naming system developed by Linnaeus ⚫1st word=genus

⚫A group of closely related organisms⚫Ex. Pinus = pine trees

⚫2nd word=species⚫Tells us something about the organism

⚫Ex. Pinus virginana

Rules for Scientific Names1. First word capitalized

2. Second word lowercase

3. Both words in italics or, if handwritten, underlined

Example:

Homo sapiens or Homo sapiens

What is wrong with these Scientific Names?•canus familiaris

•Felis Domesticus

•Equus caballus

Why use scientific names?• 4 main reasons

1. To avoid mistakes/confusion

2. To show how organisms are related

3. Because they give us information about the organism

4. Allows organisms to be easily organized

1. To avoid confusion/mistakes• So we can avoid confusion/mistakes

⚫We use some words to refer to many organisms that are

actually not closely related⚫ Black Bear & Koala Bear-

⚫ Koalas are NOT bears

2. To show how organisms are related• The first word gives us the genus, which is a related group of

organisms⚫Canus lupis=wolf⚫Canus familaris=dog⚫Canus latrans=coyote

3. The names give us some information about the organism

• It may be who discovered the species, where it is found, or a feature

• Nothura darwinii Cornus florida

Allow organisms to be easily organized•Organisms part of the same genus are grouped together⚫Phylogeny=grouping organisms based on relationships

Modern Classification• Life is broken down into categories

• 3 Domains⚫Bacteria⚫Archaea⚫Eukarya

Kingdom• Life is broken down into categories

• 6 Kingdoms⚫Domain Bacteria

⚫ Kingdom-Eubacteria

⚫Domain Archaea ⚫ Kingdom-Archaea

⚫Eukarya ⚫ Animalia

⚫ Plantae

⚫ Fungi

⚫ Protista

Eubacteria• “True” Bacteria

• Single cell

Archaea• Similar to bacteria

• Single cell

Animalia• Animal kingdom

• Many cells

Plantae• Plant kingdom

• Many cells

Fungi• Mushrooms, mold, yeast

• Many cells

Protists• Mostly one cell

• Most are microscopic

More classification levels•Phylum

•Class

•Order

•Family

•Genus

•Species

Species•A group of organisms that can reproduce and have fertile offspring

Mnemonic for remembering levels of organization• Did

• King

• Phillip

• Come

• Over

• For

• Great

• Spaghetti

• Domain

• Kingdom

• Phylum

• Class

• Order

• Family

• Genus

• Species

Tools for Identifying Organisms• Field Guide & Dichotomous Key

• Field Guide-Pictures and descriptions of organisms

Tools for Identifying Organisms• Dichotomous Key

⚫Detained list of characteristics that helps identify organism