90 likes | 453 Views
The Cell Theory. Obj : Identify the 3 parts of the cell theory Explain how a specific scientist contributed to the cell theory. What is a Cell?. Smallest basic unit of all living things Organisms are either: Unicellular—made of one cell such as bacteria or amoebas
E N D
The Cell Theory Obj: Identify the 3 parts of the cell theory Explain how a specific scientist contributed to the cell theory
What is a Cell? • Smallest basic unit of all living things • Organisms are either: • Unicellular—made of one cell such as bacteria or amoebas • Multicellular—made up of many cells such as plants and animals
The Cell Theory • All living things are made of cells • Cells are the smallest basic unit of life • All cells arose from pre-existing cells
Contributors • Robert Hooke • Discovered cells in cork in 1665 • Anton van Leuwenhoek • Father of microscopy • Discovered single organisms (in pond water) in 1673 • Schleiden and Schwann (1838 and 1839) • Schleiden—plants are made up of cells • Schwann—animals are made up of cells • Rudolf Virchow (1855) • All cells came from other cells
Prokaryotes • Pro—before • Kary—nucleus • Prokaryotes=before a true nucleus • No membrane bound organelles (just ribosomes) • No nucleus • Smaller than eukaryotic cells • Came before eukaryotes • Single stranded and circular DNA • All bacteria are prokaryotes
Eukaryotes • Eu—true • Kary—nucleus • Eukaryotes=have a true nucleus • Nucleus with a nuclear envelope • Bigger and more complex than prokaryotes • Have membrane bound organelles • Double stranded DNA in form of chromosomes • Can be uni or multicellular • Examples: animals, plants, fungi
Similarities • Contain all 4 biomolecules (carbs, lipids, proteins and nucleic acids) • Ribosomes • DNA • Metabolism • Can be unicellular • Have plasma membrane or cell wall