Download Cell Theory

Science Starter #1 – 10/10/16
O How did you study for the unit 2 test?
O How confident were you about the material?
O How can you improve your next test grade?
O TAKE A NEW GREEN SHEET
O COVER PAGE ON YOUR DESK TO BE STAMPED
Notes 3.1
Cell Theory and Cell Types
Chapter 4
pg. 69-78
LEVELS OF ORGANIZATION
Cells: Smallest unit that can perform life
processes
History: Hooke, 1665
O Discovered cells while looking at cork (plant)
O Described them as tiny boxes/rooms
O (“Cell means “small room” in Latin)
History: Leeuwenhoek, 1673
O Observed pond scum and found single-
celled organisms
O First to observe living cells
O He called them “animalcules”
History: Schleiden, 1838
O German botanist (studies plants)
O Concluded that all plants were made of cells
History: Schwann, 1839
O German zoologist (studies animals)
O Stated that all animals are made of cells
History: Virchow, 1858
O German physician
O Noted that all cells come from other cells
CELL THEORY
1. All living things are composed of cells.
2. Cells are basic units of structure and
function.
3. Cells come from pre-existing cells
BASIC PARTS OF A CELL
O Cell membrane
O Nucleus or nuclear material
O Cytoplasm
All Cells have the following in
Common
O Plasma (Cell) Membrane
O Acts as a barrier to the outside world
O Semi-permeable: Allows only certain materials
to leave and enter
All Cells have the following in
Common
O Cytoplasm
O Gel like substance
O Most reactions happen here
O Control Center (Nucleus/Nuclear Material)
O A form of DNA
O Regulates cell functions
Type of Cells
O Prokaryotic: lack membrane-bound organelles
O Unicellular
O Simple
O Capsule, cell wall, cell membrane
O Nucleoid (DNA)
O Cytoplasm
O Ribosomes
O Cilia, flagella
O Oldest living cells
O Ex: bacteria
Type of Cells
O Eukaryotic: contain a membrane-bound nucleus
and organelles
O Unicellular and multicellular
O More complex
a. Ex: Plant and animal cells