bellringer 9-19 what do you think this cartoon is about? what do you think is happening?

40
Bellringer 9-19 What do you think this cartoon is about? What do you think is happening?

Upload: kelley-thomas

Post on 27-Dec-2015

221 views

Category:

Documents


0 download

TRANSCRIPT

Bellringer 9-19

What do you think this cartoon is about?What do you think is happening?

Cells

Cells

Examples of Cells

Amoeba

Plants

Red Blood Cell

Nerve Cell

Bacteria

CellsThe Building Blocks of Life

The cell is the smallest 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”

History of Cells1665- 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

1673- 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, He also observed blood cells from fish, birds, frogs, dogs, and humansand humans•Therefore, it was known that cells are found in animals as Therefore, it was known that cells are found in animals as well as plantswell as plants

More history…

• 1838- German Botanist, Matthias Schleiden, concluded that all plant parts are made of cells

• 1839- German physiologist, Theodor Schwann, who was a close friend of Schleiden, stated that all animal tissues are composed of cells.

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.

Francesco Redi did first experiments to disprove spontaneous generation – Life comes from life - biogenesis

Compound Light Microscope• Use in class• Compound –

Eyepiece (10x) times objective lens

10x X 4x=40x10x X 10x=100x10x X 40x = 400x

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

Number of Cells in an organism

•Unicellular – composed of one cell

• Multicellular- composed of many cells that organize

1. Prokaryotes- ONLY bacteria, one celled, lack a nucleus or membrane-bound organelles

Two basic cell types

Prokaryotes

•Contains DNA

•Cell membrane & cell wall

2. Eukaryotes- (Like U-you) all other living things (plants, animals & fungi), have a nucleus and membrane-bound organelles.

May be unicellular or multicellular

Eukaryotic Cell

Contain 3 basic cell structures:

•Nucleus•Cell Membrane•Cytoplasm with organelles

Two Main Types of Eukaryotic Cells

Plant CellAnimal

Cell

“Typical” Animal Cell

“Typical” Plant Cell

Plasma (Cell) Membrane

Boundary between the internal and

external environment of

the cell.

Controls what goes in & out of

cell

Cell WallInflexible structure composed

of cellulose, found only in PLANTS and bacteria.

Supports and protects the cell.

NucleusContains DNA and controls cell

functions.The “brain” of the cell.

OrganellesOrganelles

“Little Organs”

Each has specific functions

Found throughout cytoplasm

Nuclear (envelope) Membrane

Porous membrane surrounding the

nucleus.

CytoplasmClear, jelly-like fluid

in cell. Where organelles are.

Endoplasmic Reticulum(E.R.)

Makes lipids (fats) delivery system - manufactures and transports.

Smooth and rough

E.R.Rough ER has ribosomes on the

surface.Smooth ER does not have ribosome attached

RibosomesMake proteins Each cell contains

thousandsFound on ribosomes and

floating throughout the cell

.

Golgi Apparatus (Body)

Packaging and shipping protein

(like the UPS)

VacuolesPlants have

single

large vacuole.

Stores water

Vacuoles Animals have•many small ones •store food, enzymes

LysosomesContain digestive material to breakdown old parts, bacteria

and waste.

“Mighty” Mitochondria

“Powerhouse”, makes energy for cell. Site of cellular respiration

(converts food into usable energy)

ChloroplastsFound only in plants - makes

food

Changes the sun’s energy into chemical energy (photosynthesis).Contains chlorophyll (gives plants green color)

CentrioleInvolved in cell division

Only animal cells!

Ribosomes

• Each cell contains thousands

• Make proteins

• Found on ribosomes, nuclear envelope & floating throughout the cell