Cells

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Cells

• What are they?

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Levels of living things

• Living Levels
• CELL (makes up ALL organisms)
• TISSUE (cells working together
• ORGAN (heart, brain, stomach )
• ORGAN SYSTEMS (respiratory, circulatory )
• ORGANISM

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Organisms are Grouped by their Number of Cells

• Unicellular Organisms
• Living Organism Made Up Of One Cell
• Multicellular Organisms
• Living Organism Made Up Of Many, Specialized
  Cells

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Types of cells

• Prokaryotic- Means before in Greek. Very simple.
  Before a nucleus. No nucleus.
• Eukaryotic- Eu means true. Has a true nucleus.

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Prokaryotic

• Cells that lack a nucleus or membrane-bound
  organelles
• Includes bacteria
• Simplest type of cell

http//videos.howstuffworks.com/hsw/10309-the-cell
-prokaryotic-cells-video.htm
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Eukaryotic

• Cells that HAVE a nucleus and membrane-bound
  organelles
• Includes protists, fungi, plants, and animals
• More complex type of cells
• Contains 3 basic cell structures
• Nucleus
• Cell Membrane
• Cytoplasm with organelles

http//videos.howstuffworks.com/hsw/10310-the-cell
-eukaryotic-cells-video.htm
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Organelles

• Very small (Microscopic)
• Perform various functions for a cell
• Found in the cytoplasm
• May or may not be membrane-bound

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Animal Cell Organelles
Ribosome (attached)
Nucleolus
Ribosome (free)
Nucleus
Cell Membrane
Nuclear envelope
Mitochondrion
Smooth endoplasmic reticulum
Rough endoplasmic reticulum
Centrioles
Golgi apparatus
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Plant Cell Organelles
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Cell or Plasma Membrane

• Composed of a double layer
• Surrounds outside of ALL cells
• Controls what enters or leaves the cell
• Living layer
• Lies immediately against the cell wall in plant
  cells

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Cell Wall

• Nonliving layer
• Found in plants, fungi, bacteria
• Made of cellulose in plants
• Supports and protects cell
• Found outside of the cell membrane

Cell Membrane
Cell wall
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Cytoplasm

• Cells are filled with a gelatin-like substance
  called cytoplasm
• Found in ALL cells
• Constantly flows inside the cell membrane
• Throughout cytoplasm is cytoskeleton

MICROTUBULES
MICROFILAMENTS
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Nucleus

• Controls all cell activities and is separated
  from the cytoplasm by a membrane.
• Contains the instructions for everything the cell
  does.
• These instructions are found on long, threadlike,
  hereditary material called DNA.

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Chloroplasts

• Found only in producers (organisms containing
  chlorophyll)
• Use energy from sunlight to make own food
  (glucose)
• Energy from sun stored in the Chemical Bonds of
  Sugars
• Contains its own DNA

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Mitochondria

• Powerhouse of the cell
• Generate cellular energy (ATP)
• More active cells like muscle cells have MORE
  mitochondria
• Both plants animal cells have mitochondria
• Site of CELLULAR RESPIRATION (burning glucose)

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Ribosomes

• Cells make their own proteins called Ribosomes.
• Given directions from DNA how and when to make
  proteins.
• Not membrane-bound
• Some float freely in cytoplasm other are attached
  to the endoplasmic reticulum.
• Made in the nucleolus moved into the cytoplasm

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Ribosomes

• Can be attached to Rough ER or

Be free (unattached) in the cytoplasm
17
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Endoplasmic Reticulum ER

• Extends from the nucleus to the cell membrane.
  Has a folds so materials can be made and moved
  around
• Two Types
• Smooth- Smooth ER lacks ribosomes on its surface
• Rough- Proteins are made by ribosomes on ER
  surface

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ER

• Smooth ER- No attached ribosomes processed
  cellular substances such as lipids that store
  energy.
• Rough ER- Has ribosomes attached and carry out
  the job of making proteins that are moved out of
  the cell or used in the cell.

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Golgi Bodies

• Modify, sort, package molecules (proteins) from
  ER for storage OR transport out of cell
• Packages them into vesicles for temporary
  storage.
• Stacked flattened membranes

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Vacuoles

• Fluid filled sacks for storage
• Small or absent in animal cells
• Plant cells have a large Central Vacuole

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Cell Theory

• All living things are made of cells
• Cells are the basic unit of structure and
  function in an organism (basic unit of life)
• Cells come from the reproduction of existing
  cells (cell division)

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Exceptions to the cell theory

• Viruses they are able to reproduce only within a
  living cell.
• Mitochondria and Chloroplasts
• Each contain their own genetic information
  different than that in the nucleus.

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Viruses

• A virus is a strand of hereditary material
  surrounded by a protein coating
• Dont have nucleus or other organelles
• Lack a cell membrane
• Need a host cell

H1N1