Chapter 7! Viruses, Bacteria, Protists, & Fungi! p. 208 1
Vocabulary virus! bacteria! protist! fungi! vaccine! pasteurization! parasite! host! pseudopod! flagellum! cilia! decomposer protozoan!!
Viruses Virus - a non-living particle that invades and multiples inside a living cell
Is a virus alive?! Is it an organism?
A Flu Virus
Characteristics of Viruses non-living! multiply differently than organisms! multiplies inside host! act like parasites
Host - organism on which a virus lives! Parasite - organism that lives on host and causes it harm!
Structure of Viruses smaller than cells! vary in size and shape: rods, bricks, threads, etc.! protein coat: protects virus! inner core made of genetic material: contains instructions for making new viruses! envelope: outer membrane on some viruses
Rod-shaped viruses
Structure of Viruses Each virus contains unique surface proteins. The shape of the surface proteins allows to the virus to attach to certain cells in the host. This lock and key action is specific to each virus.
How Viruses Multiply 1. Virus attaches to cell! 2. Virus enters cell! 3. Virus s genetic material takes over cell functions! 4. Instructs cell to produce virus s surface proteins and genetic material! 5. Proteins and genetic material assemble into new viruses
Active Viruses -! go into action immediately! Ex. Flu,Colds A! Common Cold! Virus
Hidden Viruses -! Genetic material becomes part of cell s genetic material, but does not appear to affect cell functions; may stay inactive for years until conditions are just right to become active!! Ex. Cold sores! Shingles
Viruses can affect people, plants, and animals. A Plant Virus
There are no cures for viral diseases.
How to Treat Viral Diseases! 1. Rest! 2. Drink fluids! 3. Eat well Why do you think each of these helps treat the virus?
Preventing Viruses Vaccine - substance introduced into the body to destroy specific disease causing viruses
M-M-R Vaccine What Diseases Does M - M - R help prevent?
Vaccines 1. Flu! 2. Polio! 3. Chicken pox! 4. Measles What are these diseases?! Use ipads to learn about them.
Bacteria Bacteria -! single celled organisms without a nucleus
Microscopic view of bacteria
Are bacteria alive?! How do you know? Hint: Characteristics of Life! Do you remember?
Are Bacteria! 1. Made of Cells?! 2. Composed of Chemicals?!! Do Bacteria! 4. Need Food & Energy?! 5. Reproduce?! 6. Grow & and Develop?! 7. Respond to their Environment?! 8. Release Waste?
Bacteria Need! Food and Energy Autotrophs or heterotrophs! Who remembers?! Autotrophs vs. heterotroph! Conduct respiration and break down food for energy
Structure of Bacteria No nucleus! Vary in size: largest about as big as a period at the end of a sentence; some only one millionth of a meter
Bacteria magnified on the head of a pin
Structure of Bacteria Shapes: spheres, rods, spirals! May have a flagellum
Structure of Bacteria Flagellum -! whip-like structure that helps a cell move
Role of Bacteria 1. Produce Oxygen! 2. Produce Foods! 3. Decomposers! 4. Environmental Recycling & Cleanup! 5. Health & Medicine
Not all Bacteria are Bad!
As Autotrophic Bacteria use the sun s energy to produce their food, they release oxygen into the air
Autotrophic bacteria releases oxygen Cyanobacteria in water is autotrophic
As Bacteria grow in certain substances they produce foods such as! cheese! pickles! yogurt! sour cream
Some bacteria cause food to spoil when they break down the foods s chemicals. Spoiled food usually smells & tastes foul and can make you sick.! To prevent this you can refrigerate or heat the food.
Pasteurization - heating food to kill bacteria Louis Pasteur! French scientist! (1822-1895)! Also developed vaccines for anthrax and rabies
What do you probably drink every day that is pasteurized?
And the Answer is
Hetereotrophic Bacteria in the soil are decomposers - organisms that break down dead organisms! They are nature s recyclers.!! Some bacteria can clean oil or chemicals and help with environmental cleanup.
Oil-eating bacteria can help clean oil spills.
Did you know many bacteria living in your body keep you healthy?! Bacteria in intestines help digest food! Bacteria compete for space with harmful bacteria! Bacteria is used to produce human insulin which helps those with diabetes!
Protists Protist -! one celled organism with a nucleus
Protists 1. Animal - like! 2. Plant -like
Animal-Like Protists Protozoan - animallike protist! With pseudopods! With cilia! With flagella! Parasites
Pseudopod -! temporary bulge or false foot, for! movement!
Amoeba with Pseudopods
Amoeba Feeding
Cilia -! tiny hairs used for movement
Paramecium with Cilia
Flagellum -! whip-like structure used for movement
Euglena with Flagellum
Who remembers - What is a parasite?
Flea
Tick
Plant-Like Protists Diatoms! Dinoflagellates! Euglenoids! Algae
When diatoms die, they slowly sink to the seabed. The buildup of trillions of these shells forms a crumbly white sediment which is used in manufacturing pool filters and abrasives,! including toothpaste.
Fungus-Like Protists Slime Molds! Water Molds! Mildews
Bread Mold Slime Mold
Mildew on Leaf
Fungi -! multi celled organisms
Characteristics of Fungi! Eukaryotes! Cell Walls! Heterotrophs! Feed by absorbing Food! Use spores to reproduce
Mushrooms
Fungi on Tree
Role of Fungi! Food! Decomposers! Fight diseases! Cause some plant diseases! Help some plant roots! Lichens
Alexander Fleming! Scotland! 1881-1955 Nobel Prize 1945
Lichen = fungus + algae or autotrophic bacteria living in mutualism;! Pioneer species
Lichens on tree!! Mutualism!! Fungus gets food produced by the algae or bacteria. Algae or bacteria get shelter, water, and minerals from the fungus.