Endosymbiotic Theory Endosymbiotic Theory proposes that eukaryotic cells arose from living communities formed by prokaryotic organisms. Endo- means inside -symbiotic means relationship

Endosymbiotic Theory Prokaryotes entered ancestral eukaryotes Prokaryotes did NOT act as a parasite by infecting the host (eukaryote) Eukaryotes did NOT digest the prokaryotes Instead, the smaller prokaryotes began LIVING inside the larger cell – giving rise to eukaryotes

Click Here For Animation Tutorial Endosymbiotic Theory 1st - Mitochondria & Chloroplasts have DNA similar to bacterial DNA. 2nd – Mitochondria & Chloroplasts have ribosomes whose size & structure resembles those of bacteria. 3rd – Like bacteria, Mitochondria & Chloroplasts reproduce by binary fission when the cells containing them divide by mitosis. Click Here For Animation Tutorial

Which of the following summarizes the Endosymbiotic Theory? Clicker Question #17 Which of the following summarizes the Endosymbiotic Theory? Mitochondria & chloroplasts in eukaryotes were once prokaryotes Ribosomes & lysosomes in eukaryotes were once prokaryotes Mitochondria & chloroplasts are now found inside prokaryotes None of the above

Which of the following are true? Clicker Question #18 Which of the following are true? Mitochondria has DNA similar to prokaryotes Ribosomes in eukaryotes are similar to prokaryotes When mitochondria create more of themselves, they divide similar to how prokaryotes divide All of the above

Viruses Virus comes from the Latin word for “poison” Virus are particles of nucleic acid, protein, and in some cases lipids that can reproduce only by infecting living cells. Viruses are so small that they can only be seen using an electron microscope. Flu Virus Ebola Virus AIDS Virus Bacteriaphage

Viruses Viruses have NO organelles! A typical virus is composed of a core of either DNA or RNA surrounded by a protein coat. Common Cold Virus Small Pox Virus Polio Virus Herpes Virus

Viruses A virus’s outer protein coat is called its capsid. A capsid is an outer protein coat that enables a virus to enter a host cell. The capsid binds to the surface of a cell and “tricks” the cell into allowing it inside.

Viruses Once inside the cell, the viral genes take over. The cell transcribes (reads and copies) the viral genes, putting the genetic program of the virus into effect. And often times the virus destroys the host cell

Click here to compare size! Viruses Vaccine: A preparation of a weakened or killed pathogen, upon injection, stimulates antibody production or cellular immunity against the pathogen but is incapable of causing severe infection (sickness). A world wide vaccination program was able to eliminate smallpox! Antibiotics NEVER cure viral infections!!...ONLY Bacteria Click here to compare size! Small pox

Viruses Video

Compare & Contrast Cells & Viruses Bacteria (cells) Both Must have host to reproduce Reproduces on their own DNA or RNA Has organelles Has NO organelles Cause disease Large in size Extremely small in size Cell wall for protection Capsid for protection

Which of the following statements is true about viruses? Clicker Question #19 Which of the following statements is true about viruses? Viruses do not have DNA Viruses must have a host to reproduce Antibiotics kill viruses Viruses have organelles

Which of the following is the smallest? Clicker Question #20 Which of the following is the smallest? White blood cell Pollen Bacteria Virus

Which of the following do viruses NOT have? Clicker Question #21 Which of the following do viruses NOT have? Organelles Capsid Genetic material They have all of the above

DNA is located here: Clicker Question #22 Chloroplast Nucleus Lysosomes Vacuoles

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