The CellThe Cell

Why study cells? organisms are made up of cells

cells do all the work of life!

THE CELL THEORYTHE CELL THEORY

1. All living things are composed of cells.

2. The cell is the basic unit of living things.

3. Cells are produced by other living cells.

The cell is the smallest unit that can carry on all the processes of life.

Spirogyra Epithelial Tissue

A cardiac muscle cellCardiac muscle

Cells Tissues

Organs Organ System Organism

Heart

Circulatory System

Cell Tissue Organ Organ System

Organism

Levels of Organization

Some organisms are unicellular--- composed of one cell.

Bacteria Paramesium Euglena

Unicellular algae --- unicellular “plant”

Some organisms are multicellular --- composed of two or more cells --- many cells.

multicellular algae

There is an enormous variety of cells on Earth.

bacteria

protozoan

algae

muscle cell

nerve cell blood cell

http://www.youtube.com/watch?v=Ln69k7LyTsU

Bacteria 1:28Euglena 2:50Diatom 4:55Amoeba 5:56DesmidVolvox 9:08Didinium eating parameciumparamecium

There are two basic types of cells: (1) Prokaryotic cells --

(2) Eukaryotic cells --

simple cells that have no nucleus and no organelles

complex cells that have a true nucleus and organelles.

1 µm= 10µm= 10-6-6 m m

There are two basic types There are two basic types of cells:of cells:

Larger 10 – 100 µmLarger 10 – 100 µm

Modern – 1 by old Modern – 1 by old

Smaller 1- 10 µmSmaller 1- 10 µmAncient- 3.5 by old Ancient- 3.5 by old

Eukaryotic cells Eukaryotic cells Prokaryotic cellsProkaryotic cells

Prokaryotic cellsProkaryotic cells Eukaryotic cellsEukaryotic cells

no organelles no organelles no nucleus no nucleus has nucleushas nucleus

has organelleshas organelles

simple – simple – complex– complex–

Prokaryotic cellsProkaryotic cells Eukaryotic cellsEukaryotic cellsExamples-Examples- Examples- Examples- (two kingdoms)(two kingdoms)

(four kingdoms) (four kingdoms)

EubacteriaEubacteria

ArchaebacteriaArchaebacteriaProtistsProtistsFungiFungiPlantsPlants

AnimalsAnimals

All cells, prokaryotes and All cells, prokaryotes and eukaryotes, have:eukaryotes, have:

Cell membraneCell membrane 

CytoplasmCytoplasm 

Chromosomes (DNA)Chromosomes (DNA) RibosomesRibosomes

- a membrane that encloses the cell and regulates what substances enter and exit the cell.

– the semifluid substance inside cells that is composed mostly of water. It also contains dissolved macromolecules and ions.

- the genetic material.

- small structures that make proteins.

A Prokaryotic Cell--- A Bacteria

Cytoplasm semifluid substanceinside cells that contain dissolved macromolecules, ions, and minerals.

Cell membrane a membrane that encloses the cell and regulates what substances enter and exit the cell.

Chromosomes (DNA)

the genetic material.Ribosomes

small structures that make proteins.

Some cells may have:Some cells may have:

Cell wall

Protects the bacteriafrom its surroundings

Provides support for the cells of plants

– rigid structure surrounding the cell membrane that provides support and protection.

(locomotion)

Some cells may have:Some cells may have:

CiliaCilia

FlagellaFlagella - long, hair-like projections.

short, numerous, hair-like projections. (locomotion & feeding)

Cell Wall

Flagella

Cilia

Flagella

Cilia

http://www.youtube.com/watch?v=QGAm6hMysTA

Your body has different organs that perform different functions…..

Cells have mini-organs

Only eukaryotic cells have membrane- bound organelles.

---mini organs

Organelles – membrane-bound structures within the cell that have specific functions.

http://www.youtube.com/watch?v=Ln69k7LyTsU

All eukaryotic cells have the following organelles:

Nucleus NucleolusEndoplasmic reticulum (ER)Golgi apparatusMitochondria

Chloroplast (plant cells only)

RibosomesVacuoles VesiclesLysosomes