1 / 12

Bacteria IN 217 & 219

Bacteria IN 217 & 219. Characteristics of Bacteria. Smallest and simplest living thing Have no organelles , including no nucleus Genetic material = simple circular chromosome They have cell walls to protect them from outside pressure Transmitted through: air Water Human Contact

moesha
Download Presentation

Bacteria IN 217 & 219

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. BacteriaIN 217 & 219

  2. Characteristics of Bacteria. • Smallestand simplest living thing • Have no organelles, including no nucleus • Genetic material = simple circular chromosome • They have cell walls to protect them from outside pressure • Transmitted through: • air • Water • Human Contact • Contaminated Food

  3. Bacterial Shape & Arrangement SHAPES: • Coccus: round • Bacillus: rod shaped • Spirillum: spirals ARRANGEMENTS: • Diplo: pairs • Staphylo: clusters • Strepto: chains

  4. Feeding Requirements • Some are heterotrophs: live as parasites • Some feed on dead material: saprobes • Some are photosynthetic: autotrophs Strep throat bacteria Blue-green bacteria

  5. Types of Metabolism Obligate aerobes: • require oxygen to live • Example: E.coli lives in mammal intestines Obligate anaerobes: • Killed in the presence of oxygen • Example: Syphillis Facultative aerobes: • can live with or w/o oxygen

  6. Bacterial Adaptations for Survival. Endospore ENDOSPORES: • Hard, outer covering produced during harsh environments • Resistant to: • drying out • boiling • Metabolism slows down inside endospore • Resumes growing when conditions are more favorable

  7. TOXIN PRODUCTION: • Some bacteria produce poisons when the Endospore begins to grow • Toxins kill off other bacteria • providing more food for the surviving bacteria • Some toxins are deadly • Examples: • Botulism (food poisoning) • Tetanus (lock jaw)

  8. Bacterial Reproduction BINARY FISSION: • Asexually Reproduce • Splitting in ½ after copying the DNA • Occurs very quickly • Will stop reproducing only if: • Run out of food • Dry up • Poisoned by own wastes

  9. CONJUGATION: • Sexual Reproduction • Transfers all or part of the DNA between 2 bacteria • Transfer through a projection called a Sex Pilli • Occurs when threatened, • Hope to pass on genetic material • Will make the bacteria resistantto changes.

  10. Describe some helpful uses for bacteria. • NITROGEN FIXATION: Some bacteria convert nitrogen gas into nitrates in the soil which is necessary for plant growth • The bacteria live in association with the plant roots • SAPROBES: Break down dead organic matter

  11. Bacterial Uses FOOD FLAVORINGS: • Food flavors are produced by: • Fermentation • Bacterial wastes, etc. • EX: Vinegar, yogurt, butter, cheese, pickles, buttermilk, sauerkraut ANTIBIOTIC PRODUCTION: • Some bacteria produce antibiotics that will kill other forms of bacteria • Antibiotics kill bacteria only!

More Related