Kingdom Monera & the Effectivenes of Antibacterial Agengs Learning Outcome E3 & E4 Kingdom Monera & the Effectivenes of Antibacterial Agengs

Student Achievement indicators Learning Outcome E3 E3 – analyse monerans as a life form at the prokaryotic level of organization Student Achievement indicators Students who have fully met this learning outcome will be able to: Examine the monerans and identify the characteristics that unify them Use examples to illustrate moneran diversity with respect to the following: classification shape and grouping of cells motility ecological role nutrition (fermentation, aerobic respiration, photosynthesis reproduction (binary fission, conjugation) human diseases Give examples of the beneficial roles of bacteria

Student Achievement indicators Learning Outcome E4 E4 – evaluate the effectiveness of various antibiotics, disinfectants, or antiseptics on bacterial cultures   Student Achievement indicators Students who have fully met this learning outcome will be able to: Conduct an experiment using sterile technique to test the effects of various antibacterial agents on bacterial cultures Analyse and interpret data from experiments to draw conclusions about the effectiveness of particular agents on specific bacteria Explain how bacteria mutate to become resistant to antibiotics

Bacteria Introduction Many bacteria have caused so many deaths that they have been credited with changing the course of human history Most microbes are harmless or even helpful They decompose dead plants and animal which allows this organic material to be recycled and put back into the ecosystem Microbes convert and recycle essential elements: carbon, oxygen, suphur and nitrogen The study of microorganisms is called Microbiology and has allowed advancements in medicine (antibiotics) and manufacturing of dairy product such as milk and cheese. Most microbes are unicellular, but unlike viruses they are capable of independent life

What is in a Name? Bacteria are named based on shape: Cocci (singular coccus) – spherical

Cocci Bacteria

What’s in a Name? Bacilli (singular bacillus) - rod-shaped

What’s in a Name? Spirilla (singular spirillum) – spiral-shaped

Classification Belong to the Kingdom Monera Includes all types of bacteria, including some simple photosynthetic and chemosynthetic organisms Two major groups: Archaebacteria Often live in environments without oxygen They are found in swamps and in environments with high salt concentration, high temperatures and high acidity. Eubacteria Are the largest group of monerans and include organisms traditionally recognized as bacteria

Basic Characteristics Bacterial cells are prokaryotic; all bacterial are single celled They cytoplasm of bacterial cells contain no membrane-bound organelles Bacterial cells have a single chromosome Most bacterial produce by binary fission Binary fission is the division of an organism into two, both new organisms would be genetically identical.

Basic Characteristics Bacteria show great metabolic diversity Some monerans are found in extreme environments where other organism can not live; boiling mud, hot springs, coal mines, polar ice caps and hot water vents. The different shaped bacteria may form chains or clusters of individually shaped cells Example streptococci is a chain of cocci bacteria Chains or clusters of bacteria do not make bacteria a multicellular organism Can form an endospore, which is a dormant state that forms during unfavorable conditions.

Respiration Obligate aerobes require oxygen in order to survive Example- mycobacterium tuberculosis Obligate anaerobes do not require oxygen in order to survive

Diseases Caused by Kingdom Monera Human diseases are caused by pathogens; usually viruses or bacteria. Although some pathogens are fungi, protozoans or parasitic worms Some of the worst human diseases are caused by bacteria Example – pneumonia Bacterial infections in lungs Treated with antibiotics Viral pneumonia is harder to treat due to a tough capsid Not affected by antibiotics

Diseases Caused by Kingdom Monera Modes of Transmission Moisture droplets in the air or dust Direct contact Fecal contamination Insect/animal bites Open cuts and wounds

Antibiotics and Antibiotic Resistance Inhibit the growth of specific microorganism 2500 naturally occurring antibiotics used to treat infections caused by bacteria Bacteria are becoming resistant to antibiotics Occurs when a mutated (resistant) bacteria reproduces This creates a new strain that is resistant to antibiotics The bacteria’s resistance is passed on the next generation

Antiobiotics & Antibiotic Resistance The most common type of bacterial resistance is caused by bacteria that have an R (resistance) factor. This factor occurs within the plasmid (ring of DNA) The plasmid codes for genes that make enzymes that deactivate certain drugs and antibiotics. Studies suggest resistant strains of bacteria have become the common or dominant type due to natural selection Read pg. 233(Bacteria and Sewage Treatment)

Examples of Harmful Bacteria Organism Disease/Destruction Produced Bacillus anthracite Anthrax Clostridium botulism Botulism; tetanus, gangrene and lock jaw Streptococci Strep throat and scarlet fever Staphylococci Boils, food poisoning an skin infections Bacilli Sours milk Pseudonymous Gasoline spoilage Destruction of silkworms Staphylococci & Pseudonymous Food spoilage Coliform bacteria   Pollution of water source, causes soft rot in plants, gastroenteritis and dysentery in humans . Spirillia Cholera and syphyillis

Gram-Positive vs. Gram-Negative Bacteria Gram-staining is done to divide bacteria into two specific groups based on cell wall content. Gram-positive bacteria are those that are stained dark blue or violet during Gram staining. Gram-negative bacteria cannot retain the crystal violet stain, instead this type of bacteria is able to take up a counterstain, and appear red or pink Gram-positive organisms are able to retain the crystal violet stain because of the high amount of peptidoglycan in their cell walls Gram-positive cell walls lack the outer membrane found in gram-positive cells.