Agenda April 15 Objective: Investigate the basic structure and cellular functions of bacteria. 1. QUIZ 2. Homework Review 3. Bacteria Guided Reading Packet 4. HOMEWORK –Bacteria Packet DUE Tomorrow –QUIZ FRIDAY!!! Bacteria and Viruses

CHAPTER 19: Bacteria and Viruses

19-1: Bacteria Prokaryotic organisms Grouped into two kingdoms –EUBACTERIA and ARCHAEABACTERIA Size ranges from 1 to 5 micrometers.

19-1: Bacterial Kingdoms ARCHAEABACTERIA –DNA sequences more similar to Eukaryotes –Anaerobic Methanogans produce methane gas EUBACTERIA –Live almost anywhere –Single cell membrane or two cell membranes

Identifying Bacteria 1. Shape ROD  Bacilli SPHERICAL  Cocci SPIRAL and CORKSCREW  Spirilla

Identifying Bacteria 2. GRAM STAINING – Two Stains used Primary stain is VIOLETCounterstain is RED Gram + bacteria contain Peptidoglycan = VIOLET Gram - bacteria contain lipids = RED 3. Movement – Flagella, Undulation, Secretions

Identifying Bacteria 3. Movement – Flagella or Undulation

4. Obtaining Energy Metabolic Diversity Chemoheterotrophs –Take in organic molecules for energy and carbon Photoheterotrophs –Use sunlight for energy –Take in organic molecules for carbon Chemoautotrophs Make carbon compounds from CO2 Use energy from chemical reactions Photoautotrophs Use sunlight similar to plants Make carbon compounds from CO2

Releasing Energy Obligate Aerobes – require oxygen –Mycobacterium tuberculosis Obligate Anaerobes – Do not require oxygen –Oxygen can kill them –Clostridium botulinum Facultative Anaerobes – survive with or without oxygen –Esherichia coli

19-2: Viruses Particles of nucleic acids, proteins, and sometimes lipids. DNA or RNA core surrounded by a protein coat Protein coat called a CAPSID –Proteins bind receptors on host cells. –Virus gains access into cell. - Very specific to cells they infect.

Virus Structures Recall phages from Chapter 12. Which scientists worked with them? Describe the experiment and its results.

Viral Infections Lytic Cycle Virus infects cell, makes copies, and bursts cell releasing new viruses Lysogenic Cycle Viral DNA is copied with host cell’s DNA Virus is copied when host cell copies itself.

Retroviruses What is a retrovirus? A virus with RNA as its genetic material. –Produces DNA from RNA template. What is an example of a retrovirus? HIV  Human Immunodeficiency Virus What disease does it cause? AIDS How does it affect the human body? Attacks immune system destroying cells

Are Viruses Living Things? Use your Textbooks to answer this question. Consider the characteristics required to qualify as being living… Viruses are not considered living things. Do not meet all 8 characteristics of life Cannot reproduce independently No growth/development Do not use/obtain energy

Diseases DISEASE BACTERIAL OR VIRAL EFFECT ON BODY TRANSMISSION West Nile V Fever, Headache, Body Aches Mosquito Bite Tetanus B Lockjaw, Joint stiffness, fever, High BP Inhalation AIDS V Helper T cells destroyed (Immune System) Blood, Body Fluids, Pregnancy Hepatitis B V Fatigue, Abdom Pain Vomiting, Joint Pain Blood, Body Fluids Common Cold V Sneezing, Sore throat, Headache, Fever Contact with objects, Inhalation Strep Throat B Fever, Sore throat, cough, Fatigue Contact with mucus or wounds

Preventing Bacterial Disease Vaccines and Antibiotics Louis Pasteur 1881 –Developd vaccine against anthrax Alexander Fleming 1928 –Discovers penicillin –Non-toxic but stops growth of pathogens Jonas Salk 1952 –Polio vaccine using a killed virus