1 THE FIVE KINGDOMS
Introduction to Bacteria 2 TYPES OF BACTERIA: Bacteria -Get food from an outside source Blue-green Bacteria -Make their own food
BACTERIA Bacteria - small one celled monerans Bacteria like a warm, dark, and moist environment They are found almost everywhere: -water-air -soil-food -skin-inside the body -on most objects
Spiral: spirilla rod-shaped: bacilli, bacillus Round: cocci 3 Shapes of Bacteria Bacteria are classified by shape into 3 groups:
3 Shapes of Bacteria Bacillus anthracis – (bacillus) Neisseria meningitidis (coccus) Leptospira interrogans – (spirilla)
6 7 Major Structures of a Bacteria Cell Capsule Cell wall Ribosomes Nucleoid Flagella Pilli Cytoplasm
7 Capsule 7 Major Structures of a Bacteria Cell keeps the cell from drying out and helps it stick to food or other cells
8 Cell wall 7 Major Structures of a Bacteria Cell Thick outer covering that maintains the overall shape of the bacterial cell
9 Ribosomes 7 Major Structures of a Bacteria Cell cell part where proteins are made Ribosomes give the cytoplasm of bacteria a granular appearance in electron micrographs
10 Nucleoid 7 Major Structures of a Bacteria Cell a ring made up of DNA
11 Flagella 7 Major Structures of a Bacteria Cell a whip-like tail that some bacteria have for locomotion
7 Major Structures of a Bacteria Cell E.coli motion
13 Pilli 7 Major Structures of a Bacteria Cell hollow hair-like structures made of protein allows bacteria to attach to other cells. Pilli-singular Pillus-plural
14 Cytoplasm 7 Major Structures of a Bacteria Cell clear jelly-like material that makes up most of the cell
15 Binary Fission- the process of one organism dividing into two organisms Fission is a type of asexual reproduction Reproduction of Bacteria How?... The one main (circular) chromosome makes a copy of itself Then it divides into two Asexual reproduction- reproduction of a living thing from only one parent
BINARY FISSION Bacteria dividing Completed Reproduction of Bacteria
The time of reproduction depends on how desirable the conditions are Bacteria can rapidly reproduce themselves in warm, dark, and moist conditions Some can reproduce every 20 minutes (one bacteria could be an ancestor to one million bacteria in six hours) Reproduction of Bacteria
Bacterial Cell & Nucleiod DNA Ring DNA replication Cell wall synthesis Cell separation
19 Bacteria Survival Endospore- a thick celled structure that forms inside the cell they are the major cause of food poisoning they can withstand boiling, freezing, and extremely dry conditions it encloses all the nuclear materials and some cytoplasm allows the bacteria to survive for many years
Bacillus subtilis Endospore-the black section in the middle highly resistant structures can withstand radiation, UV light, and boiling at 120oC for 15 minutes. Bacteria Survival
Bacteria Survival – Food sources parasites – bacteria that feed on living things saprophytes – use dead materials for food (exclusively) decomposers – get food from breaking down dead matter into simple chemicals important- because they send minerals and other materials back into the soil so other organisms can use them
Harmful Bacteria some bacteria cause diseases Animals can pass diseases to humans Communicable Disease – Disease passed from one organism to another This can happen in several ways: Air Touching clothing, food, silverware, or toothbrush Drinking water that contains bacteria
Human tooth with accumulation of bacterial plaque (smooth areas) and calcified tartar (rough areas) Harmful Bacteria
Helpful Bacteria Decomposers help recycle nutrients into the soil for other organisms to grow Bacteria grow in the stomach of a cow to break down grass and hay Most are used to make antibiotics Some bacteria help make insulin Used to make industrial chemicals
E.coli on small intestines Helpful Bacteria
26 Used to treat sewage Organic waste is consumed by the bacteria, used as nutrients by the bacteria, and is no longer present to produce odors, sludge, pollution, or unsightly mess. foods like yogurt, cottage & Swiss cheese, sour cream, buttermilk are made from bacteria that grows in milk Helpful Bacteria
27 Controlling Bacteria 3 ways to control bacteria: 1) Canning- the process of sealing food in airtight cans or jars after killing bacteria endospores are killed during this process 2) Pasteurization- process of heating milk to kill harmful bacteria 3) Dehydration- removing water from food Bacteria can’t grow when H 2 O is removed example: uncooked noodles & cold cereal
28 Controlling Bacteria Antiseptic vs. Disinfectants Antiseptic- chemicals that kill bacteria on living things means – “against infection” Examples: iodine, hydrogen peroxide, alcohol, soap, mouthwash Disinfectants- stronger chemicals that destroy bacteria on objects or nonliving things
29 BLUE-GREEN BACTERIA Autotrophs – commonly grow on water and surfaces that stay wet…such as rivers, creeks and dams larger than most bacterial cells Some live in salt water, snow, and acid water of hot springs food source for animals that live in the water – make their own food through photosynthesis
BLUE-GREEN BACTERIA Blooms- occur when the bacteria multiplies in great numbers and form scum on the top of the water can be toxic to humans and animals
Bacteria Survival Endospore- a thick celled structure that forms inside the cell it encloses all the nuclear materials and some cytoplasm They can withstand boiling, freezing, and extremely dry conditions Allows the bacteria to survive for many years
Bacillus anthracis - rod, vegetative stage prokaryote (bacterium)
Neisseria meningitidis - coccus prokaryote (bacterium)
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Leptospira interrogans - spiral shaped prokaryote (spirochete)
Photomicrograph of kidney tissue showing the presence of Leptospira bacteria.