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Bellwork - MONDAY Draw the shape of a plant and animal cell. Draw the mitochondria, nucleus & Golgi body Vocabulary Words – QUIZ WED. 1. 2. 3. 4. 5. 6. 7. 8. Virus Host Parasite Bacteriophage Bacteria Asexual reproduction Sexual reproduction Vaccine Endospore 10. Decomposer 11. Infectious disease 12. Toxin 13. Antibiotic 14. Antibiotic resistance 15. Vector 16. Pathogen 9. Words to add to your vocabulary list Vector – organism that spreads pathogens from one host to another Pathogen – an agent that causes disease Bellwork Tuesday Describe the functions of the mitochondria, nucleus, cell membrane and cell wall Have your vocabulary foldable on your desk Viruses, Bacteria, & Fungi 3.c. Describe how viruses, bacteria, fungi, and parasites may infect the human body and interfere with normal body functions (DOK 1) 3.g. Research and draw conclusions about the use of single-celled organisms in industry, in the production of food, and impacts on life (DOK 3) VIRUSES: WHAT IS A VIRUS? A tiny, non-living particle that enters into a living cell and then reproduces inside that cell. No organisms are safe from viruses From the smallest bacterial cell to the tallest tree, from your pet cat to your younger brother There is a virus able to invade that organisms cells. CHARACTERISTICS OF VIRUSES Do not have all characteristics essential for life. Are not cells Do not use their own energy to grow or to respond to their surroundings VIRUSES CANNOT MOVE ON THEIR OWN! **The only way viruses are like organisms is that they are able to multiply. A HOST An organism that provides a source of energy for a virus or another organism A virus enters and multiplies inside a host VIRUSES CAN ONLY MULTIPLY WHEN THEY ARE INSIDE A LIVING CELL A PARASITE An organism that lives on or in a host and causes it harm A virus acts like a parasite Almost all viruses destroy the cells in which they multiply VIRUS SHAPE Bacteriophage: a virus that infects bacteria Its name means “bacteria eater” Has a complex, robot like shape Round Rod Bullet shaped VIRUS SIZES Vary in sizes Smaller than cells Smaller than bacteria Cannot be seen with a regular microscope THE STRUCTURE OF VIRUSES All viruses have very similar structures even though they look very different 2 basic parts: 1. 2. A protein coat that protects the virus An inner core made of genetic material A virus’s genetic material contains the instructions for making new viruses. ***VIRUSES DO NOT HAVE A CELL WALL! PROTEINS ON THE SURFACE OF A VIRUS Play an important role during the invasion of a host cell Each virus contains unique surface proteins The shape of the surface proteins allows the virus to attach to certain cells in the host LOCK AND KEY ACTION Because the lock and key action of a virus is highly specific, a certain virus can attach only to one or a few types of cells. For example, most cold viruses infect cells only in the nose and throat of humans HOW VIRUSES MULTIPLY Once inside a cell, a virus’s genetic material takes over many of the cells functions. It instructs the cell to produce the virus’s proteins and genetic material. These proteins and genetic material then assemble into new viruses. Some viruses take over cell functions immediately Other viruses wait for a while ACTIVE VIRUSES An active virus immediately goes into action. The virus’s genetic material takes over cell functions, and the cell quickly begins to produce the virus’s proteins and genetic material Then these parts assemble into new viruses When the cell is full of viruses, it bursts open, releasing hundreds of new viruses as it dies HIDDEN VIRUSES Hidden viruses do not immediately become active They “hide” for awhile The genetic material becomes part of the cell’s genetic material The virus does not appear to affect the cell’s functions and may stay inactive for years Each time the host cell divides, the virus’s genetic material is copied along with the host cell’s genetic material Then, under certain circumstances, the virus’s genetic material becomes active It takes over the cells functions in the same way that active viruses do Soon, the cell becomes full of viruses and bursts open For example: virus that causes cold sores Vector An organism that spreads pathogens from one host to another Examples: A A A A mosquito infected with malaria raccoon infected with rabies person infected with the flu tick infected with Lyme Disease BACTERIA Discovered by Anton van Leeuwenhoek when he was looking at his tooth under a microscope Single-celled organisms They are prokaryotes Genetic material in their cells is not contained in a nucleus Lack nucleus Have a cell wall that protects the cell Genetic material is found in the cytoplasm Genetic material forms a circular shape BACTERIA CONTINUED May have a flagellum that helps it to move Flagellum spins in place like a propeller to allow the cell to move Bacteria can have many flagella, one, or none Bacteria that do not have flagella must rely on other methods for movement SHAPE OF BACTERIA 3 basic shapes: 1. 2. 3. Spherical (circular) Rod Spiral The chemical makeup of the cell wall determines the shape SIZE OF BACTERIA Vary greatly in size Larger than viruses but still very small OBTAINING FOOD AND ENERGY All bacteria need certain things to survive Bacteria must have a source of food and a way of breaking down the food to release its energy OBTAINING FOOD Autotrophs: make their own food 1. 2. Some capture and use the sun’s energy as plants do Others, such as bacteria that live deep in mud, use energy from chemical substances in their environment OBTAINING FOOD CONT’D Heterotrophs: cannot make their own food Must consume other organisms or the food that other organims make May consume a variety of food Milk, meat, decaying leaves, etc. RESPIRATION Process of breaking down food to release its energy Bacteria need a constant supply of energy to carry out their functions Most bacteria need oxygen to break down their food, but a few do not need oxygen for respiration For those bacteria, oxygen kills them REPRODUCTION When bacteria have plenty of food, the right temperature, and other suitable conditions, they thrive and reproduce frequently Under ideal conditions, some bacteria can reproduce as often as every 20 minutes! It’s a good thing that growing conditions for bacteria are rarely ideal Otherwise, there would be no room on Earth for other organims Bacteria would take over everything! REPRODUCTION There are 2 types of reproduction 1. 2. Asexual reproduction Sexual reproduction 1. ASEXUAL REPRODUCTION Reproductive process that involves only one parent and produces offspring that are identical to the parent Bacteria reproduce by a process called binary fission, in which one cell divides to form two identical cells Binary fission is a form of asexual reproduction During binary fission, a cell 1st duplicates its genetic material and then divides into 2 separate cells Each new cell gets its own complete copy of the parent cell’s genetic material 2. SEXUAL REPRODUCTION Involves 2 parents who continue their genetic material to produce a new organism, which differs from both parents Some bacteria may undergo a simple form of sexual reproduction During a process called conjugation, one bacterium transfers some of its genetic material into another bacterium through a thin, threadlike bridge that joins the two cells 2. SEXUAL REPRODUCTION CONTINUED After the transfer, the cells separate Results in bacteria with new combination of genetic material Conjugation does not increase the number of bacteria However, it does result in new bacteria that are genetically different from the parent cells The bacteria will then divide by binary fission and the new genetic material is passed to the new cells ENDOSPORE FORMATION A small, rounded, thick-walled, resting cell that forms inside a bacterial cell Contains the cell’s genetic material and some of its cytoplasm Sometimes, conditions in the environment become unfavorable for the growth of bacteria For example, food sources can disappear, water can dry up, or the temperature can fall or rise dramatically ENDOSPORE FORMATION CONTINUED Some bacteria can survive harsh conditions by forming endospores Endospores can resist freezing, heating, and drying Endospores are also light Can survive many years For example: the bacteria that causes botulism produces heat-resistant endospores that can survive in improperly canned foods Can be transported by a light breeze If an endospore lands in a place where conditions are suitable, it opens up and the bacteria can begin to grow and multiply Bellwork Wednesday – make sure you write the question. 1. 2. 3. 4. Are viruses considered cells? Can viruses move on their own? Do viruses use their own energy? Name the 4 shapes of viruses. Study for your vocabulary quiz. Answer questions in notes when finished - do not write question 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. T/F: Not all organisms can get a virus. T/F: Viruses have all characteristics that are essential for life Are viruses cells? Do viruses use their own energy? T/F: Viruses must be in a host cell in order to multiply T/F: A virus acts like a parasite. What is located on the outer coat of a virus that is specific to that virus? Are viruses considered living organisms? Can viruses move on their own? Do viruses have the ability to multiply? Bellwork Thursday Give an example of a vector. Name the 4 shapes a virus. What is on the surface of a virus? Do viruses have a cell wall? Turn in bellwork – you should have Monday, Tuesday, Wednesday, and Thursday Turn in writing prompt MAKE SURE YOUR NAME IS ON EVERYTHING! STUDY YOUR NOTES! Classwork Use 2 column note-taking strategy to take notes on the following: Usefulness of bacteria – pages 168 – 171 How disease spreads – pages 174 – 175 Treating disease – pages 176 – 178 Preventing disease – page 179 YOU WILL HAVE A QUIZ TOMORROW ON THIS INFORMATION. Bellwork – FRIDAY Which of these would happen to the cell if cellular respiration stopped? A. It would not have the energy it needs to perform its functions. B. It would grow larger because it would not be able to dispose of wastes. C. It would have to access backup energy trapped in the chemical bonds of food. D. It would no longer be able to passively transport materials across its cell membrane. ONCE YOU FINISH BELLWORK….LOOK OVER YOUR NOTES!!! Usefulness of viruses Viruses are not all bad… They can be used in a technique called gene therapy. Usefulness of bacteria 1. 2. 3. Oxygen and food production Environmental recycling and cleanup Health maintenance and food production Oxygen and Food Production Autotrophs release oxygen into the atmosphere Bacteria grow in milk to produce dairy products such as buttermilk, yogurt, sour cream, and cheeses Bacteria grow in apple cider change the cider into vinegar Can bacteria in food production be harmful? Environmental Recycling Decomposers Heterotrophic bacteria Organisms that break down large chemicals in dead organisms into smaller chemicals Nature’s recyclers They return basic chemicals to the environment for other living things to reuse Example: leaves of many trees die in autumn and drop to the ground, decomposing bacteria spend the next month breaking down the chemicals in the dead leaves, the broken down chemicals mix with the soil and can then be absorbed by the roots of nearby plants. Environmental Cleanup Some bacteria eat oil They convert the poisonous chemicals in oil into harmless substances Scientists have put these bacteria to work cleaning up oil spills in oceans and gasoline leaks in the soil under gas stations Health and Medicine Did you know that many of the bacteria living in your body actually keep you healthy? In your digestive system, your intestines teem with bacteria to help you digest food, make vitamins, or compete for space with disease-causing organisms preventing the harmful bacteria from attaching to your intestines and making you sick Some bacteria help make medicines Human insulin Viruses, Bacteria, and Your Health How Infectious Disease Spread Have you ever wondered how you “catch” a cold, strep throat, or the chickenpox? These and many other diseases are called infectious diseases – illnesses that pass from one organism to another Infectious diseases can spread through contact with an infected person, a contaminated object, an infected animal, or an environmental source. Once contact occurs, disease causing agents, such as viruses and bacteria, may enter a person through breaks in the skin, or they may be inhaled or swallowed Others may enter the body through the moist linings of the eyes, ears, nose, mouth, or other body openings Contact With An Infected Person Direct contact such as touching, hugging, or kissing an infected person can spread some infectious diseases Kissing an infected person can transmit cold sores Contact can also occur indirectly A common form of indirect contact is inhaling the tiny drops of moisture that an infected person sneezes or coughs into the air These drops of moisture may contain disease causing organisms, such as flu or cold viruses Contact With A Contaminated Object Certain viruses and bacteria can survive for a while outside a person’s body They can be spread via objects such as eating utensils Drinking from a cup used by an infected person can spread diseases such as strep throat and mononucleosis If you touch an object that an infected person has sneezed or coughed on, you may transfer some viruses and bacteria to yourself if you then touch your mouth or eyes You may also get sick if you drink water or eat food that an infected person has contaminated Contact With An Infected Animal Animal bites can transmit some serious infectious diseases to humans For example: Rabies can be transferred through the bite of an infected dog, raccoon, or some other animal Tick bites can transmit the bacteria that cause Lyme Disease Mosquitoes can spread the virus that causes encephalitis, a serious disease in which the brain tissues swell Contact With Environmental Sources Certain viruses and bacteria live naturally in food, soil, and water Poultry, eggs, and meat often contain salmonella bacteria Eating foods that contain these bacteria can lead to one type of food poisoning Cooking the foods thoroughly kills the bacteria Treating Infectious Disease Bacterial Diseases Many bacterial diseases can be cured with medications known as antibiotics A chemical that can kill bacteria without harming the person’s cells Antibiotics are made naturally by some bacteria and fungi Antibiotics such as penicillin are made in large quantities in factories Penicillin works by weakening the cell walls of bacteria and causing the cell to burst Bacterial Disease Continued If you have ever had strep throat, you know that the infection makes swallowing feel like your throat is full of barbed wire. But soon after you begin taking the antibiotic, your throat feels better The antibiotic quickly kills the bacteria that cause strep throat Since antibiotics attack cell walls, they only work on bacteria. Viruses do not have cell walls Antibiotic Resistance Results when some bacteria are able to survive in the presence of an antibiotic Antibiotics are less effective today than they once were because over the years, many bacteria have become resistant to antibiotics Example of Antibiotic Resistance The recent increase in tuberculosis cases demonstrates the impact of antibiotic resistance As patients began to take antibiotics to treat tuberculosis in the 1940s, the number of tuberculosis cases dropped significantly. Unfortunately, there were always a few tuberculosis bacteria that were resistant to the antibiotics As resistant bacteria survive and reproduce, the number of resistant bacteria increases. The number of tuberculosis cases has increased over the last 20 years Today, antibiotic resistance is a serious problem and some bacterial diseases are becoming difficult to treat Viral Diseases Unlike with bacterial diseases, there are currently no medications that can cure viral infections Viruses do not have a cell wall and since antibiotics attack the cell wall, they are not effective in curing viruses. However, many over the counter medications can help relieve symptoms Available without a prescription May make you feel better, but can also delay your recovery if you resume your normal routine while you are still sick They can also hide symptoms that would normally prompt you to go to a doctor Viral Diseases Continued The best treatment for viral infections is often bed rest Resting, drinking lots of fluids, and eating well-balanced meals may be all you can do while you recover from a viral disease Preventing Infectious Diseases Vaccines A substance introduced into the body to stimulate the production of chemicals that destroy specific viruses or bacteria May be made from dead or altered viruses or bacteria Because they are dead or altered, the viruses or bacteria in the vaccine do not cause disease Instead, they activate the body’s natural defenses, the vaccine puts the body “on alert” so if that virus or bacteria ever invades the body, it is destroyed before it can cause disease You may have been vaccinated against diseases such as polio, measles, tetanus, and chickenpox Other ways to prevent infections Eat nutritious food Get plenty of sleep Drink plenty of fluids Exercise Washing your hands often Do not share eating or drinking utensils Storing food properly Keeping kitchen equipment and surfaces clean Cooking meats well Homework 1. 2. 3. 4. 5. How are bacteria beneficial as decomposers in the soil? What kind of bacteria help provide oxygen for breathing? What role do bacterial decomposers play in the environment? A friend states that all bacteria are harmful to people. List three reasons why this statement is inaccurate. In what ways might bacteria contribute to the success of a garden in which pea plants are growing? Bellwork - MONDAY Look over your notes when you finish answering the question. INFECTIOUS DISEASES You will need to copy everything on the infectious disease slides. LYME DISEASE - bacteria Symptoms: How it spreads: Bite of an infected deer tick Treatments: Rash at site of tick bite; chills; fever; body aches; joint swelling Antibiotic Prevention: Tuck pants into socks; wear a long-sleeved shirt TUBERCULOSIS (TB) – bacteria Symptoms: How it spreads: Inhaling droplets Treatment: Fatigue; mild fever; weight loss; night sweats; cough Antibiotic Prevention: Avoid contact with people with an active infection; vaccine (for those at high risk) TETANUS (LOCKJAW) – bacteria Symptoms: How it spreads: Deep puncture wound Treatment: Stiff jaw and neck muscles; spasms; difficulty swallowing Antibiotic; opening and cleaning the wound Prevention: Vaccine STREP THROAT – bacteria Symptoms: How it spreads: Inhaling droplets; contact with a contaminated object Treatment: Fever; sore throat; swollen glands Antibiotic Prevention: Avoid contact with infected people; do not share utensils, cups, or other objects FOOD POISONING – bacteria Symptoms: How it spreads: Eating foods containing the bacteria Treatment: Vomiting; cramps; diarrhea; fever Antitoxin medicines Prevention: Properly cooking and store foods; avoid foods in rusted and swollen cans INFLUENZA (FLU) – virus Symptoms: How it spreads: Contact with contaminated objects; inhaling droplets Treatment: High fever; sore throat; headache; cough Bed rest fluids Prevention: Vaccine HEPATITIS C – virus Symptoms: How it spreads: Contact with the blood of an infected person Treatment: Oftentimes no symptoms; jaundice (yellowing of the eyes and skin); fatigue Drugs to slow viral multiplication; there is no cure Prevention: Avoid contact with infected blood CHICKENPOX – virus Symptoms: How it spreads: Contact with the rash; inhaling droplets Treatment: Fever; red, itchy rash Antiviral drug (for adults) Prevention: Vaccine ACQUIRED IMMUNODEFICIENCY SYNDROME (AIDS) – virus Symptoms: How it spreads: Sexual contact; contact with blood; pregnancy, birth, and breastfeeding Treatment: Weight loss; chronic fatigue; fever; diarrhea; frequent infections; weakening of immune system Drugs to slow viral multiplication; there is no cure Prevention: Avoid contact with infected body fluids SMALLPOX – virus Symptoms: How it spreads: Coming into contact with an infected person Treatment: Fever, backache, diarrhea, vomiting, fatigue, pink rash There is no drug to treat smallpox Prevention: Vaccine DYSENTERY - ameoba Symptoms: How it spreads: Drinking contaminated water Treatment: Extreme diarrhea, vomiting, stomach pains, fever Antibiotic Prevention: Drinking clean water You will need to know the shapes of the viruses/bacteria that cause the following diseases Tuberculosis: rod shaped bacteria Lyme disease: rod shaped bacteria Cholera: rod shaped bacteria AIDS: round virus Flu: round virus Smallpox: round virus Dysentery: amoeba FUNGUS classifies all mushrooms, mildews, yeasts, and molds. Examples of Fungi - bread molds, yeast, mushrooms Diseases caused by Fungi - Athlete's foot and Ring worm Fungal Diseases 1. Athlete’s Foot: 2. Scaling, flaking, itchy skin Person to person – contact with the fungus Treated with antifungal creams Ring Worm: Itchy, red, scaly, raised patches on skin (in shape of a ring) Fungal spores land on a person’s skin and begin to grow on surface Treated with antifungal creams