Prayer Attendance Homework Check

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PrayerAttendanceHomework Check
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Chapters 3.1-3.11What is a cell?

• Ms. Doshi

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What is a cell?

• cell
• -is the basic unit of all organisms
• We see cells in our fridge.
• Example eggs
• Most expensive egg cell caviar
• (Human sperm cells cost 1 cent for 20,000 cells)
• Eggs are the largest and most expensive cells in
  the world.

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Cell Theory

1. All living organisms are made of one or more
   cells.
2. All cells arise from other, pre-existing cells.

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2 Types of Cells

• Eukaryotic cell
• -has a nucleus, which contains the cells DNA.
• Eukaryote
• -an organism composed of eukaryotic cells
• Prokaryotic cell
• -does not have a nucleus, its DNA is in the
  cytoplasm.
• Prokaryote
• -an organism composed of prokaryotic cells

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Four Structures in all Prokaryotes

• plasma membrane
• surrounds the cells
• also known as the cell membrane
• everything inside the cell is intracellular.
• everything outside the cell is extracellular
• cytoplasm
• jelly-like fluid
• fills the inside of a cell
• ribosomes
• little granular bodies
• make proteins
• in cytoplasm
• DNA
• each prokaryote has circle DNA or linear DNA

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Additional Structures in Prokaryotes

• cell wall
• -rigid
• -protects and gives shape to the cell
• capsule
• -protective outer coating
• flagellum
• -looks like a tail
• -helps move the cell
• pili
• -helps cell to attach to other surfaces
• -helps cell to exchange DNA with other cells
  function as tubes

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The Prokaryote Basic Structure
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Prokaryotes in our Bodies

• All bacteria are prokaryotes.
• Examples
• E.coli
• -live in your intestine
• -helps your body make some essential vitamins
• Streptococcus pyogenes
• -cause strep throat

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Eukaryotic vs. Prokaryotic Cell
EUKARYOTES DNA is in a NUCLEUS They are LARGER THAN prokaryotes (10x more) CYTOPLASM contains ORGANELLES PROKARYOTES No NUCLEUS DNA is in the CYTOPLASM No ORGANELLES VERY SMALL
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Structures found in animal and plant cells.
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Where did eukaryotic cells come from?

• First, came prokaryotes.
• Then came eukaryotes.
• Where did all the organelles come from?
• Two theories
• 1. Endosymbiosis
• 2. Invagination

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Endosymbiosis (Theory)

• Best explanation for two organelles in
  eukaryotes
• -chloroplasts in plants and algae
• -mitochondria in plants and animals
• What do these 2 organelles do?
• Chloroplasts
• -help plants and algae convert (change) sunlight
  into energy for cells.
• Mitochondria
• -help plants and animals convert food and oxygen
  into energy for cells.

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Endosymbiosis
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Invagination

• Best explanation for Nucleus and Rough
  Endoplasmic Reticulum in eukaryotic cells.

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Questions

• What is a cell?
• What is the cell theory?
• What are the 2 types of cells?
• What are the 4 structures in all prokaryotes?
• What are some prokaryotes in our bodies?
• What are the differences between a eukaryotic and
  prokaryotic cell?
• Draw a prokaryotic cell. Label all of its parts.
• Draw a eukaryotic cell . Label all of its parts.
• What is the best explanation of where
  mitochondria and chloroplasts come from?
• What is the best explanation of where the nucleus
  and RER come from?