Cell Structure and Function

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Cell Structure and Function
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Discovery of Cells

• It wasnt until the 1600s that scientists were
  able to use microscopes to observe living things.

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Cells

• In 1665, Robert Hooke observed cork cells under
  the microscope. He called them cells.
• This is a drawing he made of the cork cells.

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More Cork Cells

• Here is what cork cells look like in a modern
  microscope with special lighting.

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Leeuwenhoeks Microscope

• Anton Van Leeuwenhoek used a single-lens
  microscope to view pond water and other things.
• Here is his microscope.

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Cell Theory

• The Cell Theory States
• All living things are made of cells.
• Cells are the basic units of structure and
  function in living things.
• New cells are produced from existing cells.

• It wasnt long before scientists realized that
  all living things were made up of cells. This
  discovery brought about the formulation of the
  cell theory.

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Types of Cells

• Cells are classified as prokaryotic or
  eukaryotic.
• Prokaryotic cells have genetic material that is
  not inside a nucleus. No nucleus.
• Eukaryotic cells have genetic materials in a
  nucleus. (true nucleus)

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Cell Structures

• Cells contain small structures called organelles.
  Each organelle has a specific job it performs in
  the cell.

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1.The Nucleus

• This is a membrane-bound structure that contains
  the DNA. DNA is the genetic material that is the
  code for making proteins.
• EX Chief Executive Officer (CEO)

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2. Chromatin

• The DNA and surrounding protein.
• EX blueprints to factory product

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3. Ribosomes

• Ribosomes are protein assembly organelles.
• Ribosomes can be free in the cytoplasm or on
  the endoplasmic reticulum.
• EX Workers in the assembly line

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4. Endoplasmic Reticulum

• The endoplasmic reticulum is the site where
  lipids of the cell membrane are assembled, along
  with proteins and other materials.
• It can contain ribosomes and be Rough ER or have
  no ribosomes and be Smooth ER
• EX Assembly line (where workers do their work)

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5. Golgi Apparatus

• The golgi apparatus modifies, sorts, and packages
  proteins and other materials from the ER.
• EX Finishing / packaging department

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6. Lysosomes

• Lysosomes are small organelles that contain
  enzymes.
• These enzymes breakdown lipids, carbohydrates,
  and proteins into small molecules that can be
  used by the cell.
• Lysosomes also remove junk and clutter in the
  cell.
• EX Maintenance crew

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7. Vacuoles

• Vacuoles are storage organelles.They store water,
  salts, proteins, etc.
• Plants have a large vacuole that helps plants
  support leaves and stems.
• EX storage/supply room

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8. Mitochondria

• The mitochondria is the organelle that converts
  chemical energy from food into ATP to power cell
  processes.
• EX Power plant

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9. Chloroplasts

• Chloroplasts are organelles that capture sunlight
  energy and convert it into chemical energy in a
  process known as photosynthesis.
• EX Power plant

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10. Cell Membrane

• The cell or plasma membrane surrounds the cell
  and regulates what enters and exits the cell.
• Ex shipping and receiving department of a
  factory.

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11. Cytoplasm

• The cytoplasm (cytosol) is the fluid outside the
  nucleus. It contains the organelles.
• EX factory floor where most of the products are
  assembled, finished, and shipped.

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12. Centrioles

• Centrioles are cylindrical bundles of
  microtubules that function in cell reproduction.

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Division of Labor

• In multicellular organisms, each cell has a
  specialized task to keep the organism alive.
• Specialized cells include blood, muscle, heart
  cells, etc.
• Living things are organized into the following
  hierarchy.
• 1. Cells
• 2. Tissues
• 3. Organs
• 4. Organ Systems
• 5. Organisms

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Levels of Organization

• This chart shows the increasing complexity of
  organization from tiny molecules to the whole
  biosphere.

1. Macromolecules
2. Organelles
3. Cells
4. Tissues
5. Organs
6. Organisms
7. Populations
8. Communities
9. Ecosystems
10. Biosphere