bacteria n.
Skip this Video
Loading SlideShow in 5 Seconds..
Bacteria PowerPoint Presentation
Download Presentation

Loading in 2 Seconds...

play fullscreen
1 / 35

Bacteria - PowerPoint PPT Presentation

  • Uploaded on

Bacteria. Blue book-Chapter 23 (460-477) Your book- Chapter 20(572-596). Questions? Review. Differences bet. Prok and euk cells a. no nucleus, or membrane bound organelles, no cell well, smaller What are two metabolic pathways by which cells obtain energy

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation


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.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript


Blue book-Chapter 23 (460-477)

Your book- Chapter 20(572-596)

Chapter 23 Bacteria

questions review
Questions? Review
  • Differences bet. Prok and euk cells

a. no nucleus, or membrane bound organelles, no cell well, smaller

  • What are two metabolic pathways by which cells obtain energy

a. aerobic respiration, fermentation

Chapter 23 Bacteria

objectives 23 1
Objectives 23.1
  • Explain the phylogenetic relationship between the domains Archaea, Bacteria, Eukarya
  • Identify three habitats of Archaea
  • Describe the common methods used to id bacteria
  • Identify five phyla of bacteria
  • Explain importance of nitrogen fixing bacteria for many of earths ecosystems

Chapter 23 Bacteria


Prokaryotes are the most numerous organisms on Earth. They are found almost everywhere, from the skin of a fingertip to the waters of a thermal geyser to the freezing landscape of the Antarctic. The earliest fossils of prokaryotes, which are about 2.5 billion years old, indicate that prokaryotes lived long before other forms of life evolved.

Chapter 23 Bacteria

classification review

1. Domain Bacteria

Kingdom Eubacteria

2. Domain Archaea

Kingdom Archaebacteria


1. Domain Eukarya

a. K. Protista

b. K. Fungi

C. K. Plantae

d. K. Animalia

Classification review

Chapter 23 Bacteria

two major domains
Archaea- ancient (extreme environments)


Prokaryotes- no nucleus, single-celled, live in all environments

Two major Domains

Chapter 23 Bacteria

domain archaea
Domain Archaea

Different from bacteria-

  • cell walls (NO peptidoglycan)
  • Membrane lipids
  • Genetics and metabolism
  • Found in extreme harsh environments

3 major groups:

  • Methanogens- convert Hgas and CO2 to methane gas
  • Halophiles- loves salt- live in high concentrations
  • Thermoacidophiles-acidic environment, high salt, high temps

Chapter 23 Bacteria

domain bacteria
Domain Bacteria
  • Most known prokaryotes are bacteria

3 basic shapes:

1. bacilli- rod-shaped

2. spirilla- spiral shaped

3. cocci- sphere-shaped

2 major goups

1. strepto- chains

2. staphlo- clusters

Chapter 23 Bacteria

gram stain
Gram stain
  • Used to put bacteria into categories based on cell walls
  • Gram-negative- have less peptidoglycan, absorb red dye, look pink/red in micro
  • Gram-positive- have more peptidoglycan in cells wall and look purple

Chapter 23 Bacteria

important bacterial groups
Important bacterial groups
  • Proteobacteria- nitrogen-fixing bac, convert nitrogen into usable ammonia
  • Gram-positive-
  • Cyanobacteria- use photosynthesis
  • Spirochetes- gram-neg, STDs
  • Chlamydia- gram-neg, no peptidoglycan

Chapter 23 Bacteria

objectives 23 2
Objectives 23.2
  • Describe the internal and external structure of prokaryotic cells
  • Identify the need for endospores
  • Compare four ways in which prok get energy and carbon
  • Identify the different types of environments
  • List three types of genetic recombination that prok use

Chapter 23 Bacteria

biology of prokaryotes
Biology of Prokaryotes
  • A look at prok cells under a light microscope show that they are very small. Such a view, however, leaves unexplained the complexity of the cells’ internal workings. Here, we will study the structure of prok cells and the many ways that they gather nutrients and energy and reproduce.

Chapter 23 Bacteria

structure and function
Structure and Function
  • Cell wall- shape, protection, peptidoglycan
  • Cell membrane/cytoplasm- selective barrier
  • DNA- single closed loop of double stranded DNA , Plasmids are small and self-replicating double stranded
  • Capsules- outer covering of polysaccharides, protection, made of glycocalyx (fuzzy coat of sticky sugars)
  • Pili- are short hairlike projections, help to connect to other surfaces, pass DNA
  • Endospores- gram +, thick coat for protection till conditions are good
  • Flagellum- whip like motion, movement

CD 16B.

Chapter 23 Bacteria

nutrition and metabolism

photoheterotrophs- use light energy and get carbon from other organisms

Chemohetertrophs- obtain energy and carbon from other organisms


1. photoautrophs- use light energy, CO2

2. chemoautrophs- use inorganic molecules, and CO2

Nutrition and metabolism

Chapter 23 Bacteria

prokaryotic habitats
Prokaryotic Habitats
  • Live in certain habitats based on their biochemical abilities
  • Obligate anaerobes- no O2 present
  • Faculatative anaerobes- can live w/wo
  • Obligate aerobes- must have O2

Chapter 23 Bacteria

reproduction and recombination
Reproduction and Recombination
  • Most reproduce by Binary fission
  • Prok can exchange pieces of DNA that can be added to the cell’s DNA w/o reproduction recombination

To get DNA in 3 ways:

  • Transformation- take DNA from outside
  • Conjugation- 2 prok bind and pass DNA
  • Transduction- virus changes DNA

Chapter 23 Bacteria



Binary Fission

Chapter 23 Bacteria


Transduction with a virus


Chapter 23 Bacteria

objectives 23 3
Objectives 23.3
  • Describe the ways in which bacteria can cause disease in humans
  • Explain how a bacterial population can develop resistance to antibiotics
  • Identify reason for recent increased in the numbers of certain bacterial infections
  • Identify ways of preventing a food born illness at home
  • List four industrial uses of bacteria

Chapter 23 Bacteria

bacteria and humans
Bacteria and humans

Bacteria are probably best know for the disease that they cause in humans. However, most bacteria that live on human skin are harmless, and other bacteria are used biotechnologically, as in the production of yogurt. Still, other bacteria that live in soil change atmospheric nitrogen into ammonia and nitrites, which plants use for growth

Chapter 23 Bacteria

bacteria and health
Bacteria and Health
  • Pathology- study of diseases (pathogen)

Bacteria can cause diseases by:

  • Exotoxins- toxic substances that bacteria secret into environment
  • Endotoxins- not released until the cell dies, causes fevers, body aches, diarrhea, (made of lipids and carbs)

Chapter 23 Bacteria

antibiotics and resistance
Antibiotics and resistance
  • Antibiotics affect bacteria by interfering with certain cellular activities
  • Resistances- evolution of populations of bacteria that antibiotics can no longer kill
  • Zoonosis- pass diseased from animals to humans- (


  • Industrial uses today

Chapter 23 Bacteria

Chapter 23 Bacteria

review questions
Review Questions
  • List 4 diseases caused by bacteria (see last slide)
  • Explain Antibiotic Resistance-
  • How is bacteria used in industry (discovery video)-
  • What is the difference between bacterial cell walls and plant cell walls?
  • Diff bet photoautroph and chemoautotroph?

Chapter 23 Bacteria

6. Bacteria reproduce-

7. Name 3 groups of archaea-

8. Name some characteristics of spirochetes

9. How are bacteria classified (web quest/notes)

Chapter 23 Bacteria

review answers
Review Answers
  • List 4 diseases caused by bacteria (see last slide)
  • Explain Antibiotic Resistance- evolution of populations of pathogenic bacteria that antibiotics are unable to kill
  • How is bacteria used in industry (discovery video)- bacteria are used to make and process food and chemicals. Help break down sewage and recycle carbon and nitrogen, used in mining, used to clean up oil spills, make pesticides

Chapter 23 Bacteria

4. What is the difference between bacterial cell walls and plant cell walls? BC are made of peptidoglycan and pc have cellulose

5. Diff bet photoautroph and chemoautotroph? makes carbon cpds by light energy, makes carbon by breaking down inorganic sub

6. Bacteria reproduce- binary fission

7. Name 3 groups of archaea- methanogens, halophiles, theromophiles

Chapter 23 Bacteria

8. Name some characteristics of spirochetes
  • Gram -, sprial-shaped, aerobic and anaerobic

9. How are bacteria classified (web quest/notes)

Shape, gram stain, biochemical prop, evolutionary relationships

Chapter 23 Bacteria