Bacteria and Viruses Our Microscopic World

BACTERIA smallest, simplest organism, unicellular Most abundant organism Prokaryotic cell…very simple, NO nucleus, ribosomes, cytoplasm, circular DNA, cell membrane, some have cell walls

BACTERIA CLASSIFICATION Archaebacteria “old” bacteria Found in inhospitable conditions Three types 1. Heat lovers…found in hot springs, paint pots, ocean vents 2. Methane makers…found in swamps 3. Salt lovers…found in high salt environments…ie: Dead Sea Eubacteria Most common Found everywhere Grouped by how obtain food 1. producers…make own food 2. decomposers…consumer that breaks down matter to obtain nutrients 3. parasites…consumer that obtain nutrients by feeding off other organisms

SHAPES 1. COCCI…Sphere shaped 2. BACILLI…bar shaped 3. SPIRILLA…spiral shaped https://www.google.com/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&uact=8&ved=0CAYQjB0&url=https%3A%2F%2Fwww.blendspace.com%2Flessons%2FcYyEAUxam6RvFw%2Fhonors-biology-viruses-2-prokayotes&ei=fU4IVdVihZ3IBIOTgqAH&bvm=bv.88198703,d.aWw&psig=AFQjCNGn9reYUoZdXi53VqucewwRXYNbjg&ust=1426694124873593

Bactria Reproduction… Binary Fission http://www.google.com/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&uact=8&ved=0CAYQjB0&url=http%3A%2F%2Ftechhydra.com%2Fscience%2Fbiology%2Fcellular-biology%2Fcell-division%2Fbinary-fission%2F&ei=yk4IVYPCLcOGyASHiIHwAQ&bvm=bv.88198703,d.aWw&psig=AFQjCNF83OMOqD0Yu_hK2-q-fQ1b5xFr2Q&ust=1426694215889861 Bactria Reproduction… Binary Fission Bacteria reproduce in a process called BINARY FISSION 1. Cell grows larger 2. DNA replicates and attaches to the cell membrane 3. The DNA and its copy separate as the cell grows larger 4. The cell splits in two. * each new cell contains identical DNA

For MOST bacteria…Ideal conditions for reproduction are warm and moist For MOST bacteria…Ideal conditions for reproduction are warm and moist. When conditions are not ideal, some will survive by forming and ENDOSPORE, a hard protective covering. Many bacteria can survive boiling, freezing, and extremely dry conditions. When conditions become favorable again, endospores can break open and bacteria can become active again.

Good Bacteria Nitrogen Fixing Bacteria… takes nitrogen from the air and change it to a useable form plants can use Decomposing Bacteria… breaks down dead matter so nutrients are available for new plants Bioremediation… bacteria converts pollution into harmless chemicals … used to clean up wastes, oil spills and remove toxins from soils

Good Bacteria…continued Genetically Engineered Bacteria… To produce… medicine, insecticides, cleaners, adhesives and some foods Medicines such as… ANTIBIOTICS…chemicals used to kill bacteria and other microorganisms INSULIN so diabetics are able to process sugars and carbohydrates Foods… (BLANK) to help make some sausage, some dairy products (cheese/yogurt/cottage cheese, etc), pickles

Bad Bacteria Pathogenic Bacteria (Cause disease) They invade the host and obtain nutrients from the host, weakening the host and causing damage to the host Most can be treated with ANTIBIOTICS Human Diseases caused by Bacteria… cavities, ear infections, strep throat, food poisoning Can cause disease in animals but also in plants, protists, fungi and other bacteria!

VIRUSES Particles that imitate life…

VIRUSES Microscopic particle that invades a cell, often destroying it Found everywhere Many diseases are caused by viruses Contains a protein and nucleic acid (genetic material) DO NOT eat, grow, use air Can only reproduce with HELP from a host The are NOT living!

VIRUS CLASSIFICATION Viruses are classified in many ways… Type of disease Life cycle Type of genetic material Shape

Virus Shapes http://www.biologyisfun.com/classification/3- bacteria.gif

VIRAL REPRODUCTION Viruses MUST have a host to reproduce The reproduction process is the LYTIC CYCLE A. Virus finds a host cell B. Virus enters cell OR DNA is injected into cell C. Virus’ DNA takes over control of the cell D. Cell produces new viruses E. New viruses break out of the cell and invade other cells http://faculty.ksu.edu.sa/17353/Pictures%20Library/_w/Lytic%20Cycle_jpg.jpg

Diseases Caused by Viruses Common cold Influenza Polio Chicken pox Measles Mumps

VACCINES Vaccines are used to build up an individual’s immune system by… 1. Inject a weakened or “dead” virus into the body (the shot) The body’s immune system recognizes the invader and begins to build up antibodies (an army) to fight the virus The body’s immune system is able to build up the antibodies to fight the virus because the virus is not very strong. 4. The next time the virus in introduced into the body, the body recognizes the virus and already has the antibodies (army) to fight the virus. Common vaccines: polio, measles/mumps/rubella (MMR), influenza, chicken pox, hepatitis

Infectious vs Non-infectious Non-infectious Disease…a disease that is not transmitted from person to person Infectious Disease…a disease that is caused by a pathogen (bacteria, virus, fungus, protist) can generally be transferred from person to person

Protists Microscopic organisms Found commonly in pond water Cause dysentery Don’t drink water from Mexico

Fungi Cause fungal infections Yeast infections Athletes foot

The Immune System and Disease How does your body’s defense system work?

What is your body’s defense system? Microscopic organisms and particles, such as bacteria and viruses, are all around us! A pathogen is an organism, a virus, or a protein that causes disease. Fortunately, our bodies have many ways to protect us from pathogens.

External Defenses Our skin provides external protection against pathogens that may enter the body. Our hair, nails, and sweat and oil glands provide protection. Ex: glands in our skin secrete oil that can kill pathogens. Saliva and mucus wash pathogens down our stomachs where they are digested.

Internal Defenses Most of the time, pathogens cannot get past our external defenses, however this is not always the case. Sometimes, skin is cut and pathogens enter the body. The body responds to keep as many pathogens out as possible. This is done by blood flow being increased to the injured area, causing swelling and it to turn red. This is called inflammation. Platelets then help seal the open wound.

Internal Defenses The body can also respond by raising our body temperature, or fever, to slow the growth of bacteria and other pathogens. If inflammation or fever doesn’t destroy pathogens, then the immune system responds. The immune system is tissue and white blood cells that recognize and attack foreign substances in the body.

To maintain an internal balance Your body wants a safe, stable internal environment. We call this homeostasis “same state” To keep the same state to maintain an internal balance, the body will: Sweat- to give off heat (like when your fever breaks) Shiver- muscles contract to produce heat

Treatment/Prevention of Diseases Immunity is the ability to resist or recover from an infectious disease. Our body produces memory cells to help remember a specific pathogen. A vaccine is a substance prepared from killed or weakened pathogens that is introduced to the body to produce immunity. Vaccines, or immunizations, is a way to prevent illness from some diseases Ex: flu, meningitis, measles, mumps, etc. Antibiotics is a medicine used to kill or slow the growth of bacteria or fungi. used for treatment

White Blood Cells White blood cells are the part of the immune system that fight disease.

Noninfectious Disease Diseases that are caused by hereditary or environmental factors are called noninfectious diseases. Types of noninfectious diseases include: Type 1 diabetes, hemophilia, and cancer.

Infectious Disease A disease that is caused by a pathogen is called an infectious disease. Pathogens included bacteria, fungi, and parasites, which are all alive! Infectious diseases can be picked up and passed on from one living thing to another, from person to person, or even water and food. Ex: sneezing, coughing, rusty nails, fleas, ticks, mosquitoes, etc. Types of infectious diseases include: cold, flu, mono, malaria, HIV, etc.

Brainpops Bacteria https://www.brainpop.com/science/diversityoflife/bac teria/ Virus https://www.brainpop.com/health/diseasesinjuriesan dconditions/viruses/ Immune System: https://www.brainpop.com/health/bodysystems/imm unesystem/

Next… Immunity reading Homework: ws pg 41