CELLS!

10/18/2010

WHAT ARE CELLS? Robert Hooke in 1665 first called the tiny

chambers he saw in a microscope cells. All living things are made out of cells! Cells contain living matter.

CELLS MAKE UP EVERY LIVING THING!Plants are made of CELLS!Animals are made of CELLS!Bacteria are CELLS!

Can we see them?Most cells are very small so we can’t see them

without a microscopeBUT a chicken egg is just one large cell..

THE CELL THEORY What do cells have to do with life?

1. All living things are composed of cells (you, me, plants, bugs, fish, Spiderman, Colonel Sanders, Jimmy Neutron, Bacteria, Yeast, Jackie Chan)

2. Cells are the basic units of structure and function in living things(what keeps us upright and helps us live, basically small workers responsible for how we function!)

3. New cells are produced from existing cells(they can’t just appear out of thin air…cells make new cells by dividing!)

Classifications of Life:Bacteri

a

Eubacteria

Bacteria we see everyday. Like streptococci (causes strep throat).

Archaea

Archae-bacteria

Bacteria found in extreme environments such as hot boiling water and thermal vents with no oxygen or highly acid environments.

Eukarya

Protista

Unicellular Eukaryotes: Algae and slime molds. Odds and ends animals (complex but are unicellular)

Plantae

Flowering plants, mosses, and ferns

Fungi

Mushrooms, mold, mildew. CANNOT make their own food

Animalia

Consist of complex cells, are all heterotrophs. Things like tigers, bears, penguins, humans, etc.

All life is classified into three Domains…

Each domain is divided into Kingdoms. There are six different kingdoms…

It’s important to note that both Eubacteria and Archaebacteria are Prokaryotes. All Prokaryotes are single-celled and include all types of bacteria. Eubacteria and Archaebacteria are much more genetically varied than Protists, Plants, Fungus, and Animals, which is why bacteria are divided into two kingdoms. Let’s look at some examples of organisms in each kingdom…

WHY THE CLASSIFICATIONS? You’re the scientist: Let’s figure out the

difference between Prokaryotes and Eukaryotes!

With a partner, complete the questions on your notes by examining the images. If you finish early, compare your results with another group.

PROKARYOTES AND EUKARYOTES Both Have:

CytoplasmRibosomesPlasma MembraneWith Plants: Cell WallWith (some) Animals: Flagella

Prokaryotes do not have a nucleus! Eukaryotes are more complex Eukaryotes are larger

WHY ARE CELLS NAMED THAT WAY?

From Greek words…EU means TRUE. PRO means BEFORE. KARYON means NUCLEUS.

Eukaryote = TRUE NUCLEUS; Prokaryote = BEFORE NUCLEUS.

All cells have DNA, in eukaryotes it is stored in the nucleus.

Prokaryotes don’t have a nucleus, and it floats around in the cytoplasm in things called nucleoids.

Only eukaryotes have membrane-bound organelles.

TEST YOURSELF!

Statement Prokaryotic

Eukaryotic

1. Have a nucleus

2. Have membrane-bound organelles

3. Contain genetic material (DNA)

4. Can be single or multi-celled

5. Can only be single-celled.

6. Have a plasma membrane and cytoplasm

HOW IS LIFE ORGANIZED FOR MULTI-CELLULAR ORGANISMS?

Cells make up tissues which make up organs which make up organ systems which make up organisms

We can also take it back to the atomic level..

QUESTIONS?