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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
The Cell
• Basic unit of life• Building block of all
living things• Carries out all chemical
processes of life (metabolism)
Single celled organisms
Multicellular organisms
How were cells discovered?
Scientists researched by developing and using microscopes
• 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
1605 Robert Hooke
• Looked at cork plant• Noticed it was
separated into tiny compartments which resembled jail cell
One of the first users discovered protozoa
Anton von Leeuwenhoek Ground up glass
1676 Anton von Leewenhoek
• Discovered living things in pond water
• Small single celled organisms
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
• 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?
• 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
Compound Light Microscope
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
• 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– E
x; mitochondria
– DNA
Types of Electron MicroscopesTransmission Scanning
Electron Microscopes
• 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
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
Wednesday1/14/15
• 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 organellesReproduce 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, FungiAll contain membrane bound organellesOrganelle: tiny organAll eukaryotic cells are surrounded by an extra
cellular matrix
Eukaryote: Animal Cell
Eukaryote: Plant Cell
The cell: the basic unit of life
Prokaryote Eukaryote
How are prokaryotes and eukaryotes different?
Organization of the nucleusCell 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
Eukaryote
• Multi or Single celled organisms– Protista
• Parmecium• Ameba
– Fungi• Yeast• Mushrooms
– Animal– Plant
Assessment
• Create a table showing the differences between prokaryotes and eukaryotes
Differences between prokaryote and eukaryotes
• Prokaryote Smaller Simpler cells No Nucleus No membrane bound
organelles
• Eukaryote• Large• Complex• True nucleus• All membrane bound
organelles
• AIM: How can we compare plant and animal cells?
• DO NOW: What is an organelle?• How are multicellular organisms (like the
human) organized• Explain the difference between a prokaryote
and eukaryote cell
• HW: Text read pages 155 questions 2 and 4
Levels of organization of Animals• Cell: basic unit of life• Tissue• Organ• Organ system• Organism
Animal vs Plant cell
• AIM: how do the organelles in a eukaryote cell help to make the cell one functioning unit?
• DO NOW: Where is the DNA found in a prokaryote? In a eukaryote?
• How did the very first eukaryote develop?• HOMEWORK: Due Wednesday go to the
website cellsalive.com• List and give the function of each organelle
you view
• AIM: ho do plant and animal cells differ?• DO NOW: Handout Label the parts of the
plant and animal cell Label organelles 12-21• 2- Label the parts of the animal and plant cells• HOMEWORK: Cellsalive.com
Homework Due Monday• Log on to cellsalive.com• In the left hand tool bar under Interactive
choose cell models• Read the introduction and choose take me to
the animation• View both the plant and animal cells• Create a table listing the structure and
function of each organelle
The eukaryote organelles• Organelle Name Structure Function• Nucleus nucleolus cytosol• Centrosome• Centriole• Golgi• Lysosome• Peroxisome• Secretory vesicle• Cell membrane• Mitochondria• Vacuole • Cell wall• chloroplast
The eukaryote organelles
• Organelle Name Structure Function
• Smooth ER• Rough ER• Ribosome• Cytoskeleton
• Cells Cells - Parts of the Cell Rap - YouTube
The nucleus Largest organelles The brain of the cell Control center of the cell House genetic
information Nucleolus: RNA synthesis Nuclear envelope or
membrane Double membrane
surrounding the nucleus Nuclear pores
Why is the nucleus the brain of the cell?
It houses the genetic material which controls ALL cell processes
The nucleus
• Chromosomes are made up of DNA• DNA carries genes• Genes code for physical traits
Cell membrane Plasma membrane Phospholipid bilayer Surrounds the entire cell
creating a barrier Controls movement of
molecules into and out of the cell
protection Embedded with proteins
and cholesterol molecule Creates a barrier
Fluid Mosaic
CytoplasmJelly like material found throughout the cellHolds all organellesMany chemical processes take place in the
cytoplasmMade mostly of water Houses many
molecules ,ions etc.
• AIM: how do organelle’s make the cell one functioning unit?
• DO NOW: Handout Can you identify these cell structures?
• HOMEWORK: Questions 4 and 5 page 161. reading Check page 161
Mitochondria Large organelles Contain their own DNA Power house of the cell Perform Cellular
Respiration Double membrane
structure The more energy a cell
needs, the more mitochondria it has
Ribosomes
Small organelles Make proteins from
amino acids Free or bound to ER
Endoplasmic Reticulum Rough endoplasmic
Reticulum: embedded with ribosomes: protein synthesis
Smooth endoplasmic reticulum: production of lipids
Membranes of the endoplasmic reticulum are continuous (connected) to the nuclear envelope
Golgi apparatus
Receive, Modifies, Packages and transports proteins and other molecules
to parts of the cell by vesicle formation
Exports carbohydrates and lipids out of the cell
Vesicle
Enclose substances that are being transported around the cell
Bud off of golgi apparatus
Travel through the cell
Lysosomes Animal cells only Enzyme filled sacs Usually used for food
digestion and waste removal
Break down and digest broken organelles
The cytoskeleton Network of protein
fibers Provide structure,
support, transport
Centrosome or centrioles
Animal cell only Found outside the
nucleus until cell division
Help in cell division Move to opposite ends
or poles during cell division
Practice Questions
• Which organelle contains the enzymes necessary to synthesize ATP?
• Which organelle receives, modifies and packages important cellular molecules?
Plants ONLY: chloroplast
Double membraneDouble membrane Contains chlorophyll: Contains chlorophyll:
green pigment that green pigment that absorbs lightabsorbs light
PhotosynthesisPhotosynthesis Also have their own Also have their own
DNADNA
Central Vacuole Small vacuoles are in both
Plant and Animal cells Plants have a Very LARGE
central vacuole that stores cell sap
Cell sap contains: water, nutrients, ions
Cell Wall Plant cells only Surrounds the plasma
membrane Made of Cellulose
polysaccharides Very strong provides
structure and protection
Can be seen with a compound light microscope
• How are humans similar to protista?• We are both eukaryotes• Membrane bound organelles• How are we different?• Protista are single celled living things• We are billion celled living things
Cilia and flagella For single cells, enable
entire cell to swim For cells in a tissue,
move liquid over the surface of the cell
Cilia Line membranes exposed to the environment
The endomembrane system• Genes: hold the code to
build a protein– Located in the nucleus
• Proteins are made in the ribosome
• Nuclear membrane is connected to the membrane of the ER which communicates directly with the golgi bodies
• Golgi bodies ship out biomolecules in vesicles
•
• AIM:Why are chloroplasts and mitochondria unique organelles?
• DO NOW: Review your notes from last week. Explain the Endosymbiont Theory
• HW: Textbookpg 161 questions• 1-5
Chloroplast and Mitochondria
•
Evidence to Endosymbiont Theory
• Larger organism providing the smaller with nutrients
• The smaller organism providing food and energy
• DNA in chloroplast and mitochondria is circular similar to prokaryote
• Chloroplast and mitochondria divide by binary fission
Chloroplasts and Mitochondria
• cellular organelles that may really be separate organisms
• contain their own DNA
• reproduce independently within cells
•
•
In your own words explain how the chloroplast and mitochondria
give evidence to the endosymbiont theory