Transcript Viruses
Viruses Chapter 2.1 No, not this kind! The kind that make you really physically sick. What are Viruses? 1. non-living particle, no living characteristics 2. not a cell 3. invades and multiplies inside a living cell 4. does not use energy to grow or respond to surroundings 5. needs a “Host” a source of energy (you) for the virus to multiply 6. acts like a parasite, causing harm to the host Naming Viruses 1. After a disease they caused 1. Poliomyelitis 2. Organisms they infect 1. Bacteriophage – a virus infecting bacteria 3. A place they are found 4. Scientists who discover them Polio-an infectious disease, causing motor problems, paralysis Viruses Multiply Active Viruses Makes copy after copy of new viruses Host releases viruses Hidden Viruses Sits in host Inactive All at once becomes active Cold sore Stress Hides again 5. Viruses and Living World Can cause • Disease • Death • Harm to plants and animals Can be helpful to • Scientists • Gene therapy • Medical treatment BACTERIA Two types of cells Eukaryotic Cell Contains a nucleus More evolved cell protists, fungi, animals, plants Prokaryotic Cell Contains NO nucleus Primitive (older) cell BACTERIA Bacteria Cells Discovered by Anton van Leeuwenhoek in the 1600s Unicellular organisms that contain CYTOPLASM -Holds everything RIBOSOMES-Produce Proteins Come in three shapes Spherical Rod Spiral Bacteria contains FLAGELLUM: a tail that helps them to move Two Kingdoms of Bacteria 1. Archeabacteria “Ancient” bacteria Survives in extreme temperatures Earth’s earliest life forms. 2. Eubacteria Do not live in extreme environments Millions live in your body Adds oxygen to Earth’s atmosphere Bacteria uses Respiration: breaking down food to release energy Two Types of Bacterial Reproduction Asexual Reproduction – Reproduction with only 1 parent with offspring identical to parent Binary Fission – One bacteria cell divides to form two identical cells Sexual Reproduction – • 2 parents combine genetic material to form a new, different offspring • Conjugation – One bacterium transfers genetic material to another bacterium through a thin bridge Bacteria Survival Needs Food • AUTOTROPHS •Makes their own food •Uses sun’s energy •Chemical substances algae • HETEROTROPHS •Can’t make its own food •Consumes autotrophs •Consumes other heterotrophs Food chain 1. Fuel: Uses of Bacteria • methane gas 2. Food: • cucumbers to pickles • milk to buttermilk 3. Environmental Recycling • Decomposers break down dead organisms into chemicals 4. Environmental Cleanup 5. Health & Medicine • Antibiotics Ch. 2.3 Viruses, Bacteria, and Health Infectious Diseases Illness passing from one organism to another Four Ways to get ill 1. 2. 3. 4. Contact with infected person Contaminated object Infected animal Environmental source Contact with Infected Person Touching Hugging Kissing Can transfer cold sores Sneezes Coughs Flu Through drops of infected moisture in the air Contact with Contaminated Object Viruses survive outside of the body Spread on objects Utensils Cups Toothbrushes Cell Phones iPods Computers Contaminated food/water lip gloss, chapstick, sharing or trading food Contact with an Animal Animal bites Rabies West Nile Virus Ticks Mosquitoes Mosquitoes West Nile Virus Contact with Environmental Sources Salmonella Bacteria Food poisoning Eggs, poultry, meat Botulism Food poisoning Bacteria making a toxin Common Infectious Diseases VIRAL BACTERIAL AIDS Chicken Pox Flu Measles Polio Rabies Food Poisioning Lyme Disease Strep Throat Tetanus (lockjaw) Tuberculosis Vaccines: substance stimulates production of chemicals to prevent the spread of infectious disease