Viruses, Infections, and Bacteria Chapter 19 History: Advancements ______________: Invents the first microscope _________________: First to observe bacteria and other microorganisms. Robert Hooke Leeuwenhoek I.Overview A. Prokaryotes (a.k.a. _____________): ____________, single-celled organisms that have no __________. B. Prokaryotes range from ______________. bacteria Small nuclei 1-5 micrometers II. Classifying Prokaryotes - All ____________ used to be placed in the _______________ Kingdom. - 2 major groups of bacteria: A. ______________ - The __________ of the 2 kingdoms. - Eubacteria live almost _______________. prokaryotes Monera Eubacteria larger everywhere 1. Most eubacteria have a _____________. - This protects it from ______ and maintains its _________. a. Most of these cell walls contain _________________(carbohydrate). b. Just under the cell wall is a ___________________. - Some cells have ___ membranes. cell wall injury shape peptidoglycan bilipid membrane 2 B. Archaebacteria 1. Do not have _______________ in the cell membrane and have different _____________. 2. The ________________ are more like __________________ than eubacteria. 3. They can live in very ________ environments. peptidoglycan DNA sequences archaebacteria eukaryotes harsh III. Identifying Prokaryotes A. Prokaryotes can be identified by: 1. __________ - There are __ basic types of shapes. a. ________: rod-shaped b. ________: spherical-shaped c. ________: Spiral, corkscrew-shaped shape 3 Bacilli Cocci Spirilla 2. Cell Walls - There are ___ types of cell walls. - A method called _________________ is used to tell them apart. a. In a Gram stain, a ________ dye (applied first) and a ____ dye are applied and then washed with an _____________ solution to wash out the stain. 2 Gram staining violet red alcohol b. The thick, _____________ walls of of __________________ bacteria keep the violet color of the stain. c. ______________ bacteria have ___________ peptidoglycan walls inside an _____ lipid membrane. - Alcohol dissolves the _________, removing the ______________ and leaves the counter-stain (______). petidoglycan Gram-positive Gram-negative thinner outer lipids violet dye red Typical Gram stain Gram positiveGram negative 3. Movement - Some prokaryotes move through the use of ____________. - Others _________, __________, or _________. III. Metabolic Diversity -Prokaryotes can be divided into ___ groups based on their source of ________ and whether or not they use ___________. flagella snakeglide spiral 3 energy oxygen A. Heterotrophs 1. _________________: Take in _________ molecules for energy and __________. ex- Staphylococcus aureus 2. ____________________: These are ________________, but they also need to take in organic compounds for _________. chemoheterotrophsorganic carbon Photoheterotrophs photosynthetic carbon B. Autotrophs 1. ________________: Use _________ energy to convert ____ and ____ into organic compounds (like photosynthesis). - Found in areas with a lot of _______. 2. Cyanobacteria contain ____________. 3. _______________: Make ________ compounds from _____. - Energy comes from _________________, not light. Photoautotrophslight CO 2 H20H20 sunlight Chlorophyll a Chemoautotrophsorganic CO 2 chemical reactions C. Releasing Energy 1. ____________________: Need a supply of __________. ex- Myobacterium tuberculosis (T.B.) *** obligate= ______________ 2. ______________________: Need to live where ____ oxygen is present. ex. Clostridium botulinum (Botulism) oxygen Obligate aerobes required Obligate anaerobes no 3. ________________________: Do not _______ oxygen, but can live with it. Ex. E. coli IV. Growth and Reproduction - Bacteria can grow and ________ as often as every ________. - The availability of ______ and the _________ of ________ limit the growth of bacteria populations. Facultive anaerobes need divide 20 min. food production wastes A. Binary Fission 1. Bacteria grow until they become too ________, and then they _______. 2. Like ________, the DNA _________ and then divides, creating two __________ daughter cells. a. This is ____________ reproduction. asexual large divide mitosis replicates identical B. Conjugation 1. Some bacteria can exchange _____ by extending a _______ between them. 2. ___________ is important in creating _______________________. DNA bridge Conjugation genetic diversity C. Spore Formation 1. When conditions for ________ become ______________, some bacteria will form __________. a. An _______________ is made when a bacterium creates a _______ internal wall that holds the DNA and some cytoplasm. growth unfavorable spores endospore thick 2. _________ will wait until the conditions improve and then they will __________. 3. Spores help bacterial _________, not ____________. V. Importance of Bacteria - Bacteria are ____________ in maintaining the living world. Spores germinate survival reproduction important A. Decomposers 1. Bacteria _________ nutrients and help maintain ____________in the environment. B. Nitrogen Fixers 1. ________ need __________ to make amino acids. a. Gaseous nitrogen (___) is not usable by plants. b. Bacteria in soil convert N 2 into ____ c. This is called __________________. recycle homeostasis nitrogenPlants N2N2 NH 3 nitrogen fixation C. Human Uses of Bacteria - We __________ on bacteria everyday. - Bacteria can be used to: depend Food and beverages: cheese, yogurt Cleaning up oil spills Remove waste products and poisons from water Mining minerals Making vitamins in our bodies Chapter 19-2 Viruses I.What is a Virus? Viruses: Particles that contain __________, ___________, and sometimes _________. A. Viruses ____________ by infecting ___________ cells. - Viruses can be very __________ in size and ___________. lipids survive host diverse shape nucleic acid protein B. All viruses function by entering a living cell and using the cell machinery to __________ more _________. C. Typical virus is made up of a core of ______ or ______ and surrounded by a _________ ________. - __________ viruses can have hundreds of ________. replicate viruses DNA RNAprotein coat Complex genes 1. A virus ___________ coat is called a ______________. - Special ___________ on the surface ________ to receptors on the ______ cell. - This is how the virus _________ the cell into letting it bind with it. 2. Once the ______________ is inside the viral genes are _____________. protein capsid proteins bind host tricks nucleic acid replicated Components of a virus a. This is accomplished because the host cell ____________ and ___________ the viral _____. 3. The matching of _________ on the coat to the cells ____________ makes viruses very __________ to the type of cell that they will infect. -_______________: Viruses that infect bacteria. binds injectsDNA proteins membrane specific Bacteriophage II. Viral Infection - Viruses have ___ major processes once they infect a cell. A. Lytic Infection - The _________ enters the cell, makes __________________________ and will _____ the cell by making it burst. 2 virus copies of itself kill 1. The T4 Bacteriophage a. The _______ of the bacteriophage is _________ into the cell after its protein coat binds to the membrane. b. The host cell __________ tell the difference between the _________ DNA and the ______________. c. The cell makes ________ copies of the viral DNA which get made into viral __________. DNA injected cannot host viral DNA mRNA proteins - These viral __________ then destroy the _____ of the cell. d. The _______ then uses the cells parts to make more viruses. - After the virus parts are ________________, the cell bursts releasing the new viruses. - This kills the cell in the process!! proteins DNA virus assembled The Lytic Cycle B. Lysogenic Infection - A __________ infection is ____________. - Lysogenic infection differs from a _______ infection because it does not immediately _______ the cell and it can be __________ for a long time. 1. The viral ____ that is ____________ into the hosts DNA is called a ___________. lysogenic long-term lytic killdormant DNAembedded prophage - Prophages may remain __________ for many years until it is freed from the _____ DNA. inactive host The Lysogenic Cycle III. Retroviruses A. A virus that contains _______ is called a _________________. 1. A retrovirus makes a _____ copy of its _____. - This process is called _____________ ____________________. RNA retrovirus DNA RNA reverse transcription - The DNA can act like a ___________ and remain dormant for some time. IV. Viruses and Living Cells A. Viruses must infect a __________ cell to reproduce. 1. Viruses are considered to be _________. 2. Viruses are ______________, but have many traits of life. prophage living parasites nonliving Cells Viruses DNA or RNA, and capsid Cell membrane, organelles, nucleus (DNA) Reproduce only in host cell sexual and/or asexual reproduction No growth Cells can grow can evolve Do not use energy Obtain/use energy Can reproduce Regulate gene expression Infectious Disease Chapter 19-3/40-1 Introductory Questions 1)What are 2 distinguishing characteristics of prokaryotes? 2)Compare and contrast photoautotrophs and chemoautotrophs. 3)What makes viruses specific to the cell that they invade? 4)Describe the difference between the lytic and lysogenic cycles. I.Bacterial Disease in Humans A. Key Terms - __________: A parasite capable of causing a disease in a host. - ______: Any organism that harbors another organism. - ____________: A relationship between two organisms B. ________ diseases harm people in _____ ways. Pathogen Host Symbiosis Bacterial2 1. Some directly attack _______ for ______. ex. Myobacterium tuberculosis 2. Others release ________ (poisons) that interfere with the normal activity of the host. ex. strep throat, diphtheria tissuesfood toxins a. Two Types: 1) ______________ - _______ substances _________ into host tissues 2) ______________ - Part of the cell wall from ________________________ released into host tissues. a) _____________: affect the ___________ system. b) ______________: affect the ___________ system. Exotoxins Soluble secreted Endotoxins Gram-negative bacteria Neurotoxins nervous Enterotoxins digestive C. Preventing Bacterial Disease 1. __________ can prevent many _______ diseases. 2. __________ are compounds that block the _________ and ______________ of bacteria. - Major reason for increased ______ _____________. ex- Penicillin attacks cell walls of some bacteria. Vaccinesbacterial Antibiotics growthreproduction life expectancy III. Growing and Controlling Bacteria A. Bacteria need __________ and an optimal _____________. B. There are several methods for controlling the spread of _________. 1. __________________________ 2. __________________________ 3. __________________________ food temperature bacteria Sterilization by heat Disinfectants Food processing Controlling Bacteria IV. Viral Disease in Humans A. ________ also produce disease by altering the bodys ____________. B. _______ diseases cannot be treated with _____________. V. Viroids and Prions A. Viroids: Single-stranded ____ molecules that have no ________. - Viroids infect the cell and direct the ___________ of new viroids. Viruses equillibrium Virus antibiotics RNA capsid production Viroids - These _______ the _________ of ______. B. Prions 1. These are made only of ________ and contain no _____ or _____. - It is possible that prions cause ________ by forming __________________. ex- __________ disease may be cause by a prion. disruptfunctionplants proteins DNARNA disease protein clumps Mad cow Chapter 40-1 Infectious Diseases History: Early Roots Moses Sanitation for the Jews Greeks Realized disease could be transferred through many things The Plague: Lasted for over 300 years. Killed tens of millions of people. I.Terminology - __________: Any change that __________ the ________ function of the body. - __________: Any ______________ agents. ex- Bacteria, viruses, fungi, environmental factors, inherited disorders. Diseasedisrupts normal Pathogendisease-causing II. The Germ Theory of Diseases A. Microorganisms (_________) can invade other organisms and cause disease. Took the place of spontaneous generation: belief that organisms like maggots came from nonliving things. germs III. Louis Pasteur Helped to disprove spontaneous generation with his experiments. He blocked microorganisms from entering food in a swan-necked flask, but the food still was exposed to oxygen. Developed the technique of pasteurization. Associated certain organisms with certain diseases. Pasteurs Experiment IV. Robert Koch A. Studied bacteria including anthrax 1. Recognized active cells and endospores 2. Found a way to grow bacteria in pure cultures Kochs Postulates 1)The specific causative agent must be found in every case of the disease. 2)The disease organism must be isolated in pure culture. 3)Incubation of a sample into a healthy susceptible animal must produce the same disease. 4)The disease organism must be recovered from the inoculated animal. ** One organism-one disease V. Agents of Disease - The ___________________ provides perfect _____________ conditions. A. Viruses 1. Can infect almost ________ type of organism. ex.- Smallpox, _____________, warts human body growth every common cold B. Bacteria 1. Most bacteria are __________ to us. 2. Bacteria can get us sick by: a. ______________________ b. ______________________ ex- Diphtheria, botulism, anthrax harmless destroying tissue releasing toxins Bacteria in our Body! Human Body= 10 trillion cells trillion microbes! Before birth, fetus is sterile. Normal Microflora: microorganisms that live on our body, but do not harm us. 2 Types: 1) Resident microflora 2) Transient microflora Resident and Transient Microflora Resident: Always present on or in the human body ex. Mucous membranes Transient: Can be found in some conditions where resident bacteria is already found C. Protists 1. Protist: Any __________ that is not a plant, animal, or _________. ex- Protists that cause __________ and _______________________. D. Worms 1. ____________ and _____________ can cause many diseases. ex- Schistosoma, tapeworms, hookworms organism fungi malaria African sleeping sickness Disease Parasites! E. Fungi 1. Most are ____________. 2. Some can infect the _______, mouth, throat, and even ________________. ex.- Athletes foot, ringworm harmless skin the toenails VI. The Spread of Infectious Diseases A. Physical Contact 1. Most are spread through __________ contact. - Coughing, sneezing, open wounds etc B. Contaminated Food and Water 1. Bacteria grow better in ________ cooked food. indirect partially C. Infected Animals - ___________: Animals that carry ____________ from person to person. Vectors pathogens Levels of Infection 1)Contamination: Microorganisms are present. 2)Infection: When parasitic organisms multiply inside or on the hosts body. 3)Disease: When the normal health of the host is affected by the infection. Infections Some pathogens can cause many degrees of health disruption. This is called pathogenicity. ex. Mycobacterium tuberculosis cause disease upon entering the host. Staphylococcus epidermis infect only the weak immune systems. IX. Virulence Virulence: The intensity of the disease produced by pathogens. Animal Passage: The disease gets worse as it passed along from animal to animal Ex. Influenza epidemics Attenuation: Weakening of the disease producing ability of the pathogen (ex. Rabies virus) X. Kinds of Diseases Infectious Diseases: Diseases caused by infectious agents. ex. Bacteria, viruses, fungi, etc. Noninfectious Diseases: Caused by anything else. ex. Some cancers, mutations, etc. XI. How microbes Cause Disease Virulence Factors: Structures or adaptations that help an organism cause an infection ex. Pili for adhesion to cells, toxins, protective enzymes Adherence: Attachment to the host cells surface Colonization: Invading host tissues or cells Invasiveness: The ability of a pathogen to invade or grow in host tissues How Do We Identify Bacteria? First, we must obtain a culture of the bacteria. Growing Bacteria Remember, bacteria need good conditions for rapid growth. A supply of food and an optimal temperature can be provided by the scientist (YOU!) What causes an infectious disease? Infectious diseases are caused by pathogens. Pathogens include bacteria, protozoa, fungi, viruses, and other parasites. The main sources include soil, contaminated water, and infected animals including other people. Rabies Virus Anthrax bacteria This bacteria can cause ulcers. Bacteria Culture Lab You will attempt to grow unseen bacteria in order to determine which places around the campus are the most contaminated. You will swab your own body and a non-living object around the 900 building. After you have finished, your teacher will take your cultures and grow them in an incubator. The results will be examined on Friday.