Cells notes honors bio

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Cells notes honors bio

• What is a cell?
• Two types of cells Prokaryotic vs Eukaryotic
• Organelles and their functions
• The Exception Viruses
• Transfer of materials

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What is a Cell?

• Latin for small room
• Cell theory
• All living things are composed of cells
• Cells are the basic unit of structure and
  function in living things
• New cells only come from existing cells.

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History

• 1665 Robert Hooke
• build basic microscope
• looked at cork
• dubbed the structures cells Latin for small
  room
• 1674 Anton Van Leeuwenhoek saw living cells by
  observing organisms in pond water.

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How big are cells?

• http//www.cellsalive.com/howbig.htm
• Activity putting items in order
• http//learn.genetics.utah.edu/content/cells/scale
  /

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Eukaryotic cellsPlants, animals, protists,
fungi

• Subdivided by internal membranes into different
  compartments and organelles
• DNA is enclosed by a membrane-bound nucleus
• DNA organized into chromosomes
• Plant cells have a tough cell wall, animal cells
  do not.

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Prokaryotic cells bacteria

1. Smaller than eukaryotic cells
2. Lack organelles
3. Lack a nucleus - DNA is not separated from the
   cytoplasm
4. One circular chromosome
5. Tough external walls

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Cell Membrane

• Separates inside of cell from surroundings
• Controls the passage of substances into and out
  of the cell
• lipid bilayer made of 2 layers of fats
  (lipids), with proteins embedded in it.
• selectively-permeable some types of
  substances (like water) can go through it.

Fat layer
Protein
Fat layer
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• Head region of the lipid are polar molecules so
  they are attracted to water hydrophilic
• Tails region of the lipid are nonpolar they repel
  water. hydrophobic
• These molecular properties form the separation of
  inside and outside the cell.

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Cell Wall

• In plants, algae, fungi, and prokaryotes (not
  animals)
• Protects cell and is stiff to support the cell
  (plants dont need bones their cells are stiff)
• Plant cell walls are made of cellulose a
  non-living material. Plant dies wood (cell
  wall) remains.

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Nucleus

• Contains DNA which is spread around as chromatin.
  During reproduction it is wound into chromosomes.
  
• Contains the nucleolus which are involved in
  making proteins.
• Nuclear membrane separates the chromosomes and
  nucleolus from the cytoplasm and the rest of the
  cell contains pores

Nuclear membrane
http//tbn1.google.com/images?qtbnzvRxwZkGHE07fM
http//content.answers.com/main/content/wp/en/thu
mb/5/52/300px-Diagram_human_cell_nucleus_no_text.p
ng
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Cytoplasm

• The material filling the cell inside the cell
  membrane. It is made mostly of water. Also
  contains proteins, enzymes, dissolved salts,
  sugars

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Cytoskeleton

• A system of tubes inside the cell that helps
  support it.

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Ribosomes

• Protein factories
• assemble proteins for the cell

Growing protein

• Ribosome
• attached to the endoplasmic reticulum

One Ribosome close up
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Endoplasmic Reticulum

• Rough ER holds ribosomes where proteins are
  assembled
• Smooth ER has no ribosomes and is a place where
  lipids/cell membrane is made.

http//cache.eb.com/eb/image?id63513rendTypeId4
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Golgi Apparatus

• Made of a stack of membranes
• It attaches carbohydrates and lipids to proteins
• Proteins go from ER to Golgi apparatus to final
  destination

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Vesicles transport proteins and lipids around
the cell.

• Lysosomes Contain enzymes to break down
  materials in the cell
• Peroxisomes break down fatty acids, amino acids,
  and alcohol

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Vacuole

• storage bin
• Surrounded by a membrane vacuoles store
  liquid/food/waste for the cell
• Plants often have one large vacuole

http//tbn1.google.com/images?qtbnj7oRXNj5R7IArM
http//sun.menloschool.org/cweaver/cells/c/vacuo
le/plantcell.gif
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Chloroplasts

• In plant cells (not animals)
• Where photosynthesis happens
• Filled with green chlorophyll

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Mitochondria

• Powerhouses of the cell
• Where cell respiration happens
• Break down glucose to release energy

http//tbn1.google.com/images?qtbnzvRxwZkGHE07fM
http//content.answers.com/main/content/wp/en/thu
mb/5/52/300px-Diagram_human_cell_nucleus_no_text.p
ng
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Multicellular organisms have specialized cells
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Multicellular versus unicellular

• Unicellular organisms are made of a cell that can
  perform all functions necessary for survival
• Multicellular organism have specialized cells
  that work together for survival

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Bacteria

• http//www.ted.com/talks/bonnie_bassler_on_how_bac
  teria_communicate.html Bonnie Bassler How
  bacteria "talk (18 minutes)

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Not cells Viruses

• Protein shell with nucleic acid (DNA or RNA)
  inside
• Cant reproduce by themselves
• Reproduce only in a living cell, damaging cells

Viruses infecting humans include polio,
Influenza, herpes, smallpox, chickenpox,
human immunodeficiency virus (HIV) causing
AIDS.
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Virus reproduction

• Injects viral genetic material into living cell.
• Takes over cell to make copies of itself
• Copies burst out of cell.
• Animation http//www.courses.fas.harvard.edu/bio
  text/animations/lyticcycle.html

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http//www.bbc.com/news/world-africa-26835233
Why Ebola is so dangerous video 1 minute shows
virus attaching cell
https//www.youtube.com/watch?vaM3vhZrNa7E virus
infection in a cell 313
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Fighting Infection

• http//videos.howstuffworks.com/science-channel/29
  783-100-greatest-discoveries-penicillin-video.htm
  discovery of antibiotics
• 30 sec video about vaccines and antibodies
  http//www.bbc.co.uk/schools/gcsebitesize/science/
  21c/keeping_healthy/antibiotics_drug_testingrev1.s
  html
• Specific Immunity, Antibodies https//www.youtube.
  com/watch?vYs_V6FcYD5I

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1. What is an antibiotic? 2. What is a antibody?
3. What is a vaccine?

• Describe the difference between antibiotics and a
  vaccine.

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Antibiotic resistant bacteria

• https//www.youtube.com/watch?vycv3bZuZZjA
  Evolutionary arms race, TB in Russian prisons

http//www.niaid.nih.gov/topics/antimicrobialResis
tance/Understanding/Pages/mutation.aspx
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size

• Eukaryotic cells small
• Prokaryotic (bacteria) cells smaller
• Viruses smallest

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Origin of life / Ancient Earth

• Formation of the Earth cosmic dust collected for
  100 million years.
• Liquid Earth, dense materials sank to center
  (iron core)
• Solid crust formed, gases formed atmosphere
• Early atmosphere different composition then
  today
• hydrogen cyanide, CO2, CO, Nitrogen, Hydrogen
  sulfide and water.

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timeline

• 4 billion years ago Earths crust formed
• 3.8 billion years ago surface cold enough for
  water to remain liquid. Oceans formed
• Ocean water brown of lots of iron. Little
  Oxygen in atmosphere
• 3.5 billion years ago Single celled organisms
• 2.3 billion years ago photosynthetic bacteria in
  oceans started adding lots of oxygen to
  atmosphere
• 2 billion years ago eukaryotic cells
• 1 billion years ago multicellular organisms
  developed

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Miller and Ureys Experiment 1950s

• Non-living molecules like water and methane
  forming organic molecules
• Amino acids were formed when electricity was
  passed through inorganic molecules that would
  have been found in Earths early atmosphere.

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Mitochondria and chloroplasts

• Have different DNA then the nucleus of the cell
  they are in.
• Smaller prokaryotic organisms (became
  mitochondria) started living in larger
  prokaryotic organisms (became eukaryotic animal
  cells.
• Smaller prokaryotic organisms (became
  chloroplasts) started living in larger
  prokaryotic organisms (became eukaryotic plant
  cells).

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The evolution of the cell

• http//learn.genetics.utah.edu/content/cells/organ
  elles/
• 1. What is the Endosymbiotic theory? The theory
  is that Mitochondria and chloroplasts were once
  primitive bacteria cells which inserted
  themselves in a larger primitive cell and then
  developed a symbiotic relationship to become an
  integral part of the cells processes.

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The evolution of the cell

• 2. List the pieces of evidence that support the
  theory.
• Mitochondria and chloroplasts have
• their own DNA which is separate from the DNA
  found in a eukaryotic cells nucleus
• They have a double membrane like a cell
• reproduce like bacteria replicating their own DNA
  and directing their own division

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The evolution of the cell

• 3. What is the difference between mitochondrial
  DNA and nuclear DNA? Why is mitochondrial DNA
  more useful for inheritance studies?
• Mitochondrial DNA is a copy of the mothers
  mitochondrial DNA not a combination of 2 parents.
• Mitochondiral DNA is passed directly from mother
  to child so it does not accumulate changes as
  fast as nuclear DNA.

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organisms became complex because

• Eukaryotic cells started reproducing sexually
• sexually (mix of parental DNA)
• asexually (exact copies)
• Cells started coordinating to form multi-cellular
  organisms.

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Protists lab

• Kingdom Protista the protists
• video segment 7 minutes united streaming
• http//www.youtube.com/watch?v0-6dzU4gOJo 3
  minutes dramatic trailer style introduction to
  protists great microscopy