Bellringer 10/07 What do you think this cartoon is about? What do you think is happening?

The Story of Cells

What are we made of?

What are cells? The Building Blocks of Life The cell is the smallest structural unit capable of performing life functions.

Cell Trivia The average human being is composed of around 100 Trillion individual cells!!! It would take as many as 50 cells to cover the area of a dot on the letter “ i ”

Discovery of Cells English Scientist, Robert Hooke, discovered cells while looking at a thin slice of cork (bark of tree) –He described the cells as tiny boxes or a honeycomb –He thought that cells only existed in plants and fungi

The Microscope! Anton von Leuwenhoek, invented the microscope and observed pond scum and discovered single celled organisms He called them “animalcules”He called them “animalcules” He also observed blood cells from fish, birds, frogs, dogs, and humansHe also observed blood cells from fish, birds, frogs, dogs, and humans Therefore, it was known that cells are found in animals as well as plantsTherefore, it was known that cells are found in animals as well as plants

More history… German Botanist, Matthias Schleiden, concluded that all plant parts are made of cells German physiologist, Theodor Schwann, who was a close friend of Schleiden, stated that all animal tissues are composed of cells Rudolf Virchow, German physician, after extensive study of cellular pathology, concluded that cells must start from preexisting cells.

The Compound Light Microscope Lenses Light We’ll be using it!!! x1500

Our Microscope…

The Electron Microscope Biggest magnification (X 2,000,000 2 types (SEM and TEM)

The Cell Theory 1. All organisms are composed of one or more cells. 2. The Cell is the smallest working unit of living things. 3. All cells come from pre-existing cells through cell division.

Basic Parts of a Cell All cells have certain structures in common. 1. Nucleus- contains genetic material (DNA) 2. Cytoplasm – a semifluid matrix (like the eggwhite of an egg) 3. Plasma membrane – a phospholipid bilayer- like the shell of an egg 4. Organelles- specialized structures in the cytoplasm

1st Look at THE CELL!!!

Examples of Cells Amoeba Plants Red Blood Cell Nerve Cell Bacteria

To do… Get pen and pencil ready Grab sheet of paper in the middle of the room Sit quietly so we can begin Log in if you can- if not, wait so we can look up your password –Username: fiLName –Password: CpsID# –Instr

Two Types of Cells ProkaryoticEukeryotic REMEMBER US

Prokaryotic Cells Do not have a membrane-bound nucleus or organelles Few internal structures (organelles) Usually one-celled organisms like bacterias

Eukaryotic Cells They do contain a membrane-bound nucleus and organelles and are more complex. May be unicellular or multicellular Plant Animal

“Typical” Animal Cell

“Typical” Plant Cell

Cell Parts Organelles

Surrounding the Cell

Cell Membrane Outer membrane of cell that controls movement in and out of the cell Double layer

Cell Wall Most commonly found in plant cells & bacteria Supports & protects cells

Inside the Cell

Nucleus Directs cell activities Separated from cytoplasm by nuclear membrane Contains genetic material - DNA

Nuclear Membrane Surrounds nucleus Made of two layers Openings allow material to enter and leave nucleus

Chromosomes In nucleus Made of DNA Contain instructions for traits & characteristics

Nucleolus Inside nucleus Contains RNA to build proteins

Cytoplasm Gel-like mixture Surrounded by cell membrane Contains hereditary material

Endoplasmic Reticulum Moves materials around in cell Smooth type: lacks ribosomes Rough type (pictured): ribosomes embedded in surface

Ribosomes Each cell contains thousands Make proteins Found on ribosomes & floating throughout the cell

Mitochondria Produces energy through chemical reactions – breaking down fats & carbohydrates Controls level of water and other materials in cell Recycles and decomposes proteins, fats, and carbohydrates

Golgi Bodies Protein 'packaging plant' Move materials within the cell Move materials out of the cell

Lysosome Digestive 'plant' for proteins, fats, and carbohydrates Transports undigested material to cell membrane for removal Cell breaks down if lysosome explodes

Vacuoles Membrane-bound sacs for storage, digestion, and waste removal Contains water solution Help plants maintain shape

Chloroplast Usually found in plant cells Contains green chlorophyll Where photosynthesis takes place

The BIG Picture again!

QUIZ TIME PROKARYOTE OR EUKERYOTE?

Let’s compare…