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Chapter 23 Bacteria Section 1 Vocabulary Pretest Prokaryote Peptidoglycan Methanogen Halophile Thermoacidophile Bacillus Coccus Spirillum Streptococcus Staphylococcus Gram-negative bacteria Gram-positive bacteria Prokaryotes Most _________________________________on Earth Found ________________________________ Fossils date back _____________ (first forms of life) Single cells with _________________________ Major __________________________________ for many organisms Important ____________________ in the environment Divided into ____________________: __________________________ __________________________ Domain Archaea Archaea = __________________ (_____________) Differ from other prokaryotes in the following ways: Cell walls ___________________________________________ Have ________________ (portions of DNA that do not code for proteins) Live in _________________________________ Different ____________ in cell membranes rRNA resembles ______________________________ Genes resemble ______________________________ Archaeal Groups __________________________: Convert hydrogen gas and carbon dioxide into _____________________. ______________________ Live in ______________________________________________________ __________________________: “_____________________” archaea Live in very high salt concentrations (_______________________________) __________________________: Live in ___________________________ (pH <2) with very _____________ ______________________ (>230 degrees F). Ex: Hot _______________________ of Yellowstone National Park; deep water thermal vents (__________________________) Domain Bacteria Unlike archaea, members of the domain bacteria: Have cell walls with ___________________________ Have ____________________ Live in a _______________________________________ Have ___________________________ rRNA is _________________ rRNA of eukaryotes Genes are __________________ eukaryotes genes Bacteria come in a few basic shapes: ____________________ (rod-shaped): streptobacilli (chains) ________________ (sphere-shaped):streptococci (chains): staphylococci (clusters) ________________ (spiral-shaped) _________________ (corkscrew) _________________ (comma-shaped) Gram Stain A staining technique called the _______________________ illustrates a fundamental difference between two categories of bacteria: the ____________________________ and the _________________________ bacteria. Gram negative have complex cells walls with _____________________________. They stain a ______________________. Gram positive have simpler cell walls with ________________________________. They stain a __________________________. Bacterial Groups Classifying bacteria based on ____________________________________ has been difficult because bacteria can pick or genes from their environment through ___________________________. Most scientists recognize the following groups: _____________________________: Very ________________ and _________________ group Include: ________________________________ that live in nodules inside the roots of legumes (peas, beans, alfalfa, and clover). These bacteria convert atmospheric nitrogen to ammonia, which plants can use. Also includes some ________________________________ such as ________________ bacteria (causes Rocky Mountain Spotted Fever) and ___________________________ (causes stomach ulcers) Also includes _______________________ (symbiotic bacteria that live in intestinal tracts of humans and animals)Ex: ______________ lives in our intestines and secretes vitamin K as well as assisting in the digestive breakdown of foods. Other strands of _____________ and _____________________ cause _____________________________ Gram-Positive Bacteria _________________________: will stain purple when gram stain is applied. Examples include: ______________________: causes strep throat _________________________: causes botulism also used in botox injections ______________________: sours milk; used in yogurt ______________________: causes anthrax ____________________: soil bacteria used to make many antibiotics Cyanobacteria ____________________________: photosynthetic bacteria Earth’s _______________________________________ and are believed to be responsible for transforming Earth’s early atmosphere Some grow in long ______________________ Some form specialized cells called _______________________ which can __________________________ Spirochetes _________________________ are gram-negative spiral-shaped bacteria. Move with a ____________________________ Can be ________________________________________ Ex: __________________________________: causes syphilis __________________________________: causes Lyme disease Chlamydia Chlamydia are gram-negative bacteria that live only inside animal cells. There cell walls lack peptidoglycan Ex: __________________________________: causes chlamydia (sexually transmitted disease) and trachoma eye disease, a leading cause of blindness. Section 2 Vocabulary Pretest Plasmid Capsule Glycocalyx Pilus Endospore Heterotroph Autotroph Phototroph Chemotroph Obligate anaerobe Facultative anaerobe Obligate aerobe Transformation Conjugation Transduction Structure and Function General prokaryotic structure includes: _____________________________ _____________________________ _____________________________ _____________________________ _____________________________ _____________________________ _____________________________ ______________________________ Cell wall Provides ____________________________________ Made of _________________________ and _____________________________ (only on gram negative) Many _____________________ are designed to kill bacteria by breaking down the peptidoglycans of their cell walls. They are most effective on _________________ ______________________. Cell Membrane Also called the ___________________________, the cell membrane controls what gets in or out of the bacteria cell. Consists of a ____________________________________ Contains _______________________________ for respiration and photosynthesis DNA DNA of prokaryotes consists of a ________________________________________ Located in a central area called the _____________________________ Most bacteria also have small rings of DNA called ____________________ _________________________ Not necessary for ______________________ Often carry genes that allow bacteria to ________________________ Often carry genes that provide bacteria to become ____________________ ___________________________ Capsules Many bacteria have an outer covering of _______________________ called a _______________________ Their function: ______________________ from drying out Protection from ____________________________________________ Fuzzy _______________________________ allow bacteria to connect to host cells and tissues (often appears as a “____________” around stained bacteria cells Pili ___________ are short, hairlike projections that help bacteria ______________ __________________ and to host cells and other surfaces. Can _________________________ to pass genetic material Endospores _____________________ form in ___________________________________ when environmental conditions become ________________. They can resist ______________________________________________________. Cell copies its DNA and then forms a thick, protective covering around this copy. Most of the water is removed and the endospore becomes __________________ _____________________________. The rest of the cell will die, but the endospore, with its DNA cargo can remain viable for centuries. It will ____________________ when environmental conditions become favorable. Can only be killed if heated to very _____________________________________. Prokaryotic Movement Some move by _________________ Movement _______________________ from a stimulus is called ___________ __________________ =response to chemical stimuli such as food or toxins. __________________ =response to light http://www.youtube.com/watch?v=6p9e0oolbmE Nutrition and Metabolism Two basic needs exist for prokaryotes: Source of _____________________ Source of ____________________ Two ways to obtain the carbon source: _____________________: obtain carbon from ______________________ _____________________: obtain carbon from _________ Two ways to obtain the energy source: ___________________: obtain energy from ________________ ___________________: obtain energy from _________________ Major Bacterial Nutritional Modes These needs can be used to divide prokaryotes into four nutritional groups: Nutritional Mode Energy and Carbon Source Heterotroph Uses light energy but gets its carbon from other organisms Obtains both energy and carbon from other organisms Autotroph Uses light energy and gets carbon from CO 2 Extracts energy from inorganic compounds and uses CO as a carbon source 2 Prokaryotic Habitats Habitats occupied are based on biochemical abilities of different types of bacteria. Oxygen requirements: __________________________________ cannot live in the presence of oxygen. Ex: _____________________________ ____________________________ can live with or without oxygen. Ex: ________ ___________________________ require oxygen to live. Ex: ______________________________ Temperature requirements: o ______________________________: “cold-loving” grow well in 32-68 F. Can survive Antarctic temps by growing under the surface of rocks. ______________________________: grow well in moderate temperatures o between 68-104 F. ______________________________: grow well in very hot temperatures o between 113-230 F. pH requirements: Most bacteria thrive in pHs between __________________________ __________________________ are bacteria that thrive in low pHs (below 6) Reproduction Usually reproduce by _________________________ ________________________________ ________________________________ DNA molecules move to ____________ _______________________ Two _____________________________ are formed Recombination Recombination occurs when prokaryotes exchange pieces of DNA without reproduction. Three ways recombination can occur: _________________________ —a prokaryote takes DNA from its outside environment. _________________________ —two prokaryotes bind together and one cell transfers DNA to the other through a sex pilus. _________________________ —viruses transfer pieces of one prokaryotes DNA to another Transformation often involves _________________ and __________________________ Conjugation involves something called the __________________to be present in the donor cell. Transduction involves ________________________________ that carry _____________ ______________________________________. Section 3 Vocabulary Pretest Pathology Exotoxin Endotoxin Antibiotic resistance Zoonosis Bioremediation Bacteria and Humans Roles of bacteria: ______________________________ ______________________________ ______________________________ ______________________________ ______________________________ Bacteria and Health _______________________ —study of diseases ___________________: disease causing agents Some bacteria cause disease by ______________________________________. Ex: ______________________ Some bacteria cause disease by secreting _________________: __________________ —toxins secreted by bacteria into their environment. Ex: Clostridium tetani secretes toxins that cause ________________ ___________________ —toxins released after the bacteria cell dies. They can cause fever, body aches, diarrhea, hemorrhage and weakness. Ex: E. coli Antibiotics __________________ are substances used to __________________________. Made naturally by some ______________________________ __________________________________ or fungi that compete for resources Some (________________) interfere with the formation of __________________ by breaking down __________________________ Some (_________________) interfere with _________________________ Antibiotic Resistance ______________________________ is the evolution of populations of pathogenic bacteria that antibiotics are _________________________. Because of over-prescription of antibiotics, many resistant genes are now on ____________________ which can easily pass from one bacteria to the next by ____________________________. This leads to multiple resistances to many antibiotics… __________________! Emerging and Infectious Bacterial diseases Most emerging diseases develop when infectious agents, such as bacteria, pass from wild animals to humans _________________ —a disease that can pass from animal to human Zoonotic disease are on the rise due to: _____________________________________ _____________________________________ Food and Hygiene and Bacteria Foodborne illnesses result from the __________________________________________ ___________________________. To avoid: Wash all _______________________________________ Wash hands and all utensils during ________________________ Refrigerate ______________________ (eggs and lunchmeats) ________________________ thoroughly Refrigerate leftovers ___________________ Methods of food preparation Several methods can be used to prevent food spoilage by bacteria: Foods can be ___________________________: Sausages and hams _______________________: Milk and eggs Adding ______________________________________: Jellies and jams _________________ adds acids which slow bacterial growth: Pickles and relishes Cooking at _____________________: Meat products ____________________________: canned foods Adding _______________________: bread, juice and fruits Bacteria and Industry Used in _____________________________: Buttermilk, sour cream, yogurt, cheeses, sauerkraut, pickles, coffee, and soy sauce Used in _____________________________: Acetone, acetic acid, enzymes, antibiotics and insulin Used to help break down ________________ and added to laundry detergent to __________________________ Used in some _____________________ Used in ____________________________ to breakdown pollutants Used in _______________________________________