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AIM: How did Scientists discover cells? DO NOW: List at least 3 cells in your body and explain their function. HW: textbook page 153 reading check question. Basic unit of life Building block of all living things Carries out all chemical processes of life (metabolism). The Cell.
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AIM: How did Scientists discover cells? • DO NOW: List at least 3 cells in your body and explain their function. • HW: textbook page 153 reading check question
Basic unit of life Building block of all living things Carries out all chemical processes of life (metabolism) The Cell
How were cells discovered? Scientists researched by developing and using microscopes
Wednesday 11/7/12 • AIM: How did Scientists discover cells? • DO NOW: Explain why a cell is the basic unit of life • HW:Text Read page 146 B and 151-152. Reading Check page 151 • Quarterly Exam Next Thursday 11/15/12 • First day of school-the cell
Who discovered the first microscope 1590 Hans and Zacharias Janssen It is not quite certain who invented the microscope
Robert Hooke discovered cell 1605-1703
Looked at cork plant Noticed it was separated into tiny compartments which resembled jail cell 1605 Robert Hooke
One of the first users discovered protozoa Anton von Leeuwenhoek Ground up glass
Discovered living things in pond water Small single celled organisms 1676 Anton von Leewenhoek
1839 Theodor Schwann • Looked at animal tissue and saw that animals also were made up of cells
Theodor Schwann • Discovered cells which surround and support nerve cells in a human being • Called them Schwann cells
1881 Matthias Schleiden • Looked at the details of animal cells • Animal cells are made up of tiny units called organelles
Francisco Redi • Living things come from other living things • Maggots come from flies which lay eggs on decaying meat
1855 Rudolf Virchow • Cells come from preexisting cells
Development of the cell theory • With all of the research and discoveries made through the years, scientists developed an explanation or theory about living things • This was called the cell theory
The Cell Theory: an explanation of living things • All living organisms are composed of one or more cells • The cell is the basic unit of structure and organization of all living organisms • Cells come from preexisting cells
Assessment • In your own words explain how the cell theory was developed
Tuesday 11/13/12 • AIM: How are eukaryotes different from prokaryotes? • DO NOW: do you have any characteristics in common with a plant cell? Mold? Ameba? If so what are they? • Homework: Text page 150 Using words questions 1 and 2
Tuesday 11/13/12 • AIM: How were cells discovered? • DO NOW: The Cell Theory Handout • Homework: Text Read pages 146B and 151-152. • Q1:Reading Check on page 152. • Q2:Who is Lynn Margulus? • Q3:What is the Endosymbiont theory?
Compound light microscope • Uses a beam of light to magnify an image • Uses 2 magnifying lenses • Objective lense • Ocular lense • Total magnification= magnification of the objective lens x magnification of theocular lens • Magnifies 40-400 times • Allows us to view large parts or organelles of the cell
Wednesday 11/14/12 • AIM: How are eukarytoes different from prokaryotes? • DO NOW: Explain how the compound light microscope helps us investigate the cell. • HOMEWORK: Text page 150 questions 1 and 2
Electron Microscopes • Most modern microscopes • Use a beam of electrons to make the object extremely bright • Magnifies 1,000,000 x • Can not see living material • Used to see extremely small details and parts of a cell • Ex; mitochondria • DNA
Types of Electron Microscopes Transmission Scanning
Transmission electron Microscope Can only created a 2D image or flat image Scanning Electron electron Microscope Scans the surface of a cell Creates a 3D image Electron Microscopes
Scanning Electron Microscope (SEM) Scans the surface of a specimen with a beam of electrons Creates a 3d image Magnify up to 200,000 times
Transmission Electron Microscope (TEM) Beam of electrons transmits through the entire specimen If electrons can pass through the specimen it creates a light and dark image Thicker parts of the specimen are darker than thinner parts Total magnification of 200,000 x
Explain the difference between the light and electron microscopes
Wednesday 11/14/12 • AIM: How do prokaryotes and eukaryotes differ? • DO NOW: do you have any characteristics in common with a plant cell? Mold? Ameba? If so what are they? • Homework:.Text page 150 Using words questions 1 and 2
The cell: • the basic unit of life
Lynn Margulus • Endosymbiont theory: eukaryotes develop from a symbiotic relationship between prokaryotes • Evidence: chloroplast and mitochondria
2 basic types of cells • Prokaryote • No nucleus • There are no separations between each of its parts • Ex:Bacteria • Archaebacteria • Eukaryote • True nucleus: DNA is surrounded by a membrane • Ex: • Plant, Animal, Fungus, Monera
Prokaryotes: Bacteria and Archae • Prokaryote (Greek - Before Nucleus) • Prokaryotes were first group of organic organisms to evolve 3.8 BYA • Prokaryote cells lack membrane organelles • Reproduce asexually by division
Prokaryotes: Bacteria • Blue-Green Algae (Cyanobacteria)
Archaebacteria: Live in extreme environments • "methane-makers" • live in swamps, mud, sewage, and animal guts • "salt-lovers" • salt lakes, volcanic vents on the seafloor • "heat-lovers" • hot springs and other very hot places such as the thermal vents of the sea floor where temperatures exceed 110o
Eukaryotic cells • There are 2 types we will discuss, plants and animal cells • Plant, Animal, Protists, Fungi • All contain membrane bound organelles • Organelle: tiny organ • All eukaryotic cells are surrounded by an extra cellular matrix
The cell: the basic unit of life Prokaryote Eukaryote
How are prokaryotes and eukaryotes different? Organization of the nucleus Cell size Membrane bound organelles
Cell types • Prokaryote • Kingdom Monera • Bacteria • Archaebacteria • Eukaryote • Kingdom Protista • Kingdom Fungi • Kingdom Plant • Kingdom Animal
What do all eukaryotic cells have in common? Membrane bound organelles