Cells, Cells and more Cells

1
Cells, Cells and more Cells

• Part One
• Cell Theory and Structure

2
The Cell

• All living things are made of CELLS!!
• Cells are the smallest functional unit of life
  meaning they are the smallest thing that can live
  on its own
• The are they basic
• units of life

3
How was the cell discovered?

• Mid 1600s 2 different scientists discovered the
  cell in 2 different areas of
• the world
• 1. Robert Hooke
• English
• With the use of early compound microscopes, he
  was able to look at cork (plant material)
• He used the word cell because he thought they
  looked like small rooms

4
How was the cell discovered?

• 2. Anton von Leevenhoek
• Dutch
• With use of single-lens microscope, he observed
  pond water and other living things
• While doing his research he
• found what he called animacules, which we now
  call protists

5
Further Cell Evidence

• Matthias Schleiden
• 1838
• All plants were made of individual cells
• Theodore Schwann
• 1839
• Animals were also made up of cells
• Rudolf Virchow
• 1855
• New cells can only come from the division of
  existing cells
• All of these discoveries led to the development
  of the CELL THEORY

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Cell Theory Three Concepts

1. All living things are composed of one or more
   cells
2. Cells are the basic unit of structure and
   function in living things
3. New cells are produced from existing cells

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Cell Classification

• Two types of cells, based on whether they contain
  a nucleus
• Prokaryotes
• Cells that do not have nuclei or
• membrane bound organelles
• Simple, but can still carry out
• functions of all living things
• Eukaryotes
• Cells that contain nuclei and
• other membrane bound organelles
• Genetic material is separated from the rest of
  the cell

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Eukaryotes

• Have specific parts of them that perform specific
  jobs called organelles
• Organelles literally means little organs
• Kind of like a city or a
• factory everything
• has its own job that
• makes the whole thing
• function

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Eukaryotes Organelles

• Two major parts
• 1. Cytoplasm
• JOB hold organelles in place
• Portion of the cell outside the nucleus
• Contains all other organelles
• The fluid that is inside the cell

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Eukaryotes Organelles

• 2. Nucleus
• JOB Contains nearly all of the cells DNA
• Holds instructions for the cell
• Cells Brain
• Parts
• Nuclear Envelope
• JOB Surrounds the nucleus
• Chromatin
• JOB DNA that is bound to protein
• Chromosomes
• JOB Contain all the genetic material passed on
  from one generation of cells to the next
• Nucleolus
• JOB Small, dense region that is where the
  assembly of ribosomes begins

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Eukaryotes Organelles

• Ribosomes
• Small particles of RNA and protein
• Found throughout the cytoplasm
• JOB Make proteins

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Eukaryotes Organelles

• Endoplasmic Reticulum (ER)
• Internal membrane system
• Rough ER
• Has ribosomes attached to it
• JOB Assemble and fold proteins
• Smooth ER
• JOB Pathway through the
• cytoplasm
• cell membrane to nuclear
• membrane
• JOB Produces lipids for the cell

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Eukaryotes Organelles

• Golgi Apparatus
• Stacklike membranes
• JOB modifies, sorts and packages proteins
• PROTEINS
• Ribosomes ER Golgi Apparatus

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Eukaryotes Organelles

• Lysosomes
• Small organelles filled with enzymes
• JOB Digestion/Breakdown of lipids, carbohydrates
  and proteins into smaller particles that can be
  used by the rest of the cell
• JOB Breaking down other organelles that have
  outlived their usefulness

15
Eukaryotes Organelles

• Vacuole
• Sack-like structure
• JOB Store materials such as water, salts,
  proteins and carboyhdrates

16
Eukaryotes Organelles

• Mitochondria
• Powerhouse of the cell
• Site of respiration
• Have their own DNA and manufacture some of their
  own proteins
• JOB convert chemical
• energy stored in food into
• useful compounds
• Feeds the cell
• Inherited from mother
• only
• Surrounded by two
• membranes

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Eukaryotes Organelles

• Chloroplasts
• JOB capture energy from sun and convert it into
  chemical energy (photosynthesis)
• Solar power plant
• Contains chlorophyll green pigment that
  captures sun and makes plants green
• Surrounded by two membranes
• Have some of their own DNA

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Mitochondria and Chloroplasts

• Have their own genetic material
• Double membranes
• Led to the idea that they were once independent
  organisms that were at one point digested by a
  larger organism to create a symbiotic relationship

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Eukaryotes Organelles

• Cytoskeleton
• JOB support structure
• and help with transportation
• Protein filaments
• that help the cell to
• maintain its shape
• Also involved
• in movement
• (cytoplasmic
• streaming)

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Eukaryotes Organelles

• Cell Boundaries
• Cell Membrane
• JOB regulates what enters and leaves the cell
  while providing protection and support
• Lipid bilayer fluid mosaic model
• Cell Wall
• JOB support and protection

21
Eukaryotes

• 2 Types
• Animal
• Smaller Vacuole
• Plant
• Larger (Central) Vacuole
• Chloroplasts
• Cell Wall