Ch 7 Sec 2 Inside the Eukaryotic Cells

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Ch 7 Sec 2Inside the Eukaryotic Cells

• Theres a lot going on!

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Introduction

• Eukaryotic cells (unlike prokaryotic cells) have
  many structures inside them.
• Organelle small body found in the cytoplasm of
  a cell perform specialized functions.

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Holding a Cells Shape

• Cytoskeleton web of protein fibers that support
  the cell, organizes the organelles and acts as a
  highway for information molecules.
• Microfilaments long and thin, contract and
  expand to alter the cells shape
• Microtubules thin and hollow, allow information
  molecules to travel from place to place.
• Intermediate fibers moderately thick, anchor
  organelles.

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OrganellesDirecting Cellular Activity

• Nucleus
• Enclosed in nuclear envelope
• Has nuclear pores to allow molecules in and out
• Holds DNA in a lock box
• When DNA must be used, RNA comes into the nucleus
  to make a copy of these master plans.
• Dark area inside nucleus is nucleolus.
• Where ribosome parts are assembled.
• Nucleus is like the control center of the cell.

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OrganellesDirecting Cellular Activity

• Ribosomes
• Made of RNA.
• Makes proteins and holds them inside.
• May be free or bound to organelles.
• Free Ribosomes proteins for building new
  organelles
• Bound Ribosomes proteins are exported from
  cell, proteins for communication
• Packaged in vesicles to leave cell.
• Can switch from free to bound.
• Ribosomes are like transport vehicles.

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OrganellesProtein Processing

• Endoplasmic Reticulum
• Function moves proteins (made
• by ribosomes) through the cell.
• Can do this b/c the membrane of
• the ER is connected to the nuclear envelope.
• Rough ER
• Has attached ribosomes
• Proteins leave ribosomes, cross into rough ER
• Rough ER puts proteins into vesicles to move
  around the cell.
• Smooth ER
• No attached ribosomes
• Makes enzymes to make lipids, breaking down
  toxins, etc.
• ER is like a conveyor belt.

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OrganellesProtein Processing

• Golgi Apparatus
• Function modifies, sorts and packages proteins.
• Vesicles containing original proteins (from the
  Rough ER) enter Golgi.
• Enzymes in the Golgi modify the proteins into
  their final form.
• Finished proteins leave the Golgi (in a new
  vesicle) and leave the cell through the cell
  membrane.
• Golgi apparatus is like the final stop where a
  product is boxed up and shipped out.

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A Proteins Journey

• Nucleus holds DNA (master plans), makes
  ribosomes.
• Ribosomes make proteins from master plans.
• Ribosomes take proteins to the Rough ER, which
  puts proteins into vesicles.
• Vesicles travel to Golgi Apparatus, where
  modification, sorting and packaging (in a new
  vesicle) occurs.
• Vesicles of finished protein leave the cell.

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OrganellesStorage and Maintenance

• Lysosome
• Function Contains digestive enzymes that break
  down large food molecules recycles old, damaged
  or unused organelles
• More numerous in animal
• cells.
• WORD PART ALERT
• lys to break apart
• Lysosomes are like
• garbage trucks.

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OrganellesStorage and Maintenance

• Vacuoles
• Function stores water or food.
• Plants
• Have a large water filled
• central vacuole.
• Gives plants their rigid structure.
• Animals
• Have many small water and
• food vacuoles.
• Vacuoles are like storage
• compartments.

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OrganellesEnergy Production

• Chloroplasts
• Function uses light energy to make
• sugar photosynthesis.
• ONLY in plants.
• Amylosplast
• Function non-pigmented chloroplast
• Mitochondria
• Makes ATP, primary source of energy for the cell.
• Muscle cells have WAY more mitochondria than
  other cell types.

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OrganellesCell Division

• Centriole
• Organelle made of a circular
  arrangement of microtubules
• Functions in cell division, where
  it duplicates itself.
• Centrosome
• Organelle that organizes the
  microtubules of the centriole
  (holds them together).
• Controls the steps of cell division.

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OrganellesMovement

• Flagella
• Long, whip-like tail
• Used for locomotion.
• May have one or many.
• Cillia
• Short hair-like tail.
• Used for locomotion.

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Plant vs. Animal Cell
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Plant vs. Animal Cell