bio 2 lab1-2

Classification

Feeding Strategies

Heterotrophs - consume organic matter

Autotrophs- make their own food (organic from inorganic)

Mixotrophs - Become Heterotrophs when light isn’t available

Photo autotrophs - use light as an energy source chemo autotrophs-use chemicals as an energy source

Chemo heterotrophs - Organic compounds they consume are energy

Photo heterotroph-use light as energy to break down their food

Oxygen Requirements

aerobes = need oxygen

anaerobes = no oxygen

Obligate Aerobe - Need O2

Obligate Anaerobe - Grows without O2

Facultative anaerobes - Grows without oxygen but better with

Aerotolerant Anaerobe - Grows equally w/o 02

Microanophiles - Small amount of O2 needed

Shapes

Cocci = round (Strep-in lines, Staph- clusters)

Bacillus = Rod

Filamentous = No division, just grows longer, segments inside film

Helical = Spirals ( also called Spirillum)

Staining

Gram Positive = purple (massive Pepto-layer)

Gram Negative = Red membrane, (small pepto-layer membrane.).

Acid fast test

Red = Gram Positive +

Blue = Gram Negative -

Prokaryotic cells

Characteristics:

- Single circular chromosome

- 70s ribosomes (found Primarily in prokaryaic Cells and are smaller)

- Cell walls made of peptidoglycan

-No membrane bound organelles

History

- first prokaryote appeared 3.5 billion years ago

- Fossil prokaryotes formed fossilized stromatolites

• stromatolites are layer rock formations of micro-organisms

- On earth alone for 1.4 billion years (2.1 billion year ago)

- found in Most habitats on earth

Bacteria

Colonies

Mold(fungi) - Form Fluffy, cottony on filamentous appearance.

bacteria - form smooth or glossy surface

Antibiotic

Characteristics for them to work

• Presence or absence of cell wall

• Ribosome structure

• Details of their metabolism

Types

Narrow Spectrum Antibiotic - Works on either gram positive or negative bacteria

Broad Spectrum Antibiotic - Works on both gram positive and negative bacteria

Pigments

Photo synthesis - green

UV Protection - Red

Luminescent

• Found at deeps seas and soils

• Enzyme luciferase give light

• Help with plant infections, antibodies in milk, toxic pollutants in the environment, and dangerous bacteria in food

Bacteria Classification

Prokaryote Classfications

-Carl Woese used molecular bio (small ribosomal RNA) to separate Monera into different domains

Main Groups

Proteobactería - has Photo autotrophic, Chemo auto tropic, Chemoheterotropic

Spirochetes

Chlamydias

Cyano bacteria

Gram-positive bacteria

Archaea

• Ist anchaea called extremophiles: split into 2 types

• halophiles

• thermopiles

Bacteria Classification

• To determine class, compare highly conserved genes in different species (test using Polymorse chain reaction (PCR)

• Classifcation is difficult as bacteria can do horizontal gene transfer (75% of genome made by this

• Clinicians rely on bacteria morphology and staining property of the organism, oxygen growth requirements and nutrition

Domain: Bacteria

• Group: Proteobacteria

• E. coli

• bacillus shape, gram negative, facultative anaerobe

• Causes Diarrhea

• Exotoxin- releases proteins that cause illness

Found in humans intestinal tract

Some stains have fimbrae (fingers)

• Major causes of outbreak in u.S!

• Raw milk, undercooked hambunger

Domain: Bacteria

Group: Gram positive bacteria

• Bacillus anthracis

• Bacillus shape (endospore)

• Aerobic

• Causes pustules, pneumonia

Group: Chlamydias

General characteristics

• Cocus

Gram negative

Lack peptidoglycan in cell walls

very small so we can’t have an example

• Found intra cellular

• transmitted via contact or by airborne respiratory routes

Chlamydia trachomatis

- Common cause of blindness in the world and most common STI

Station 12 - Domain: Bacteria Group: Spirochetes

1. What shape do these organisms demonstrate?

Helical- spiral

2. What are the nutritional requirements for this organism? chemo heterotrophs

3. What is the name of the special structure involved in this group's movement?

Fibrils (axial filaments)

4. Where can thís group be found?

aquatic environments, in bodies of animals

5. Be able to recognize the example Treponema pallidum

a) What disease does Treponema pallidum cause?

syphilis

b) What are the four stages and symptoms of this disease?

Stage 1 - Pink to red raised sore (chancre)

Stage 2 - Rash that doesn't itch

Stage 3- No external symptoms

Stage 4 - Permanent damage to vital organs and death

c) How is this disease transmitted and what are the requirements for transmission?

warm, moist skin or moist membrane surfaces to penetrate the body

Transfer via sex, kissing or other intimate body contact

d) What is the oxygen requirement for Treponema pallidum?

essentially anarchic

Domain: Bacteria

Group: Cyanobacteria

1. What are the nutritional requirements for most of the bacteria in this group?

photo auto trophic

2. What are the oxygen requirements for the bacteria in this group?

Anaerobic and aerobic

3. What s the name of the pigment that gives the bacera in this group their blue green color Phycocyanin

1. What are the two processes that are only found together in this group of organisms? release Or and fix nitrogen

2. Where can Cyanobacteria be found?

In marine environments and some symbiotic relationships

6. Be able to recognize the prepared and live examples of Oscillatoria

1. Where can Oscillatoria be found?

   freshwater

2. What shape does Oscillatoria demonstrate?
   filamentouS form

c) What causes Oscillatoria to go through a "bloom"?

synthetic detergents

d) What is the eventual outcome of these "blooms"!

The removal of all oxygen in water and results in death of other organisms.

Domain: Bacteria

Group: Gram-positive bacteria

1. What type of gram stain do most of the bacteria in this group demonstrate?

gram positive

1. What are the nutritional requirements for most of the bacteria in this group?

   chemo heterotrophs

2. Be able to recogntle the example
   the example of Clostridium tetani

1. Is Clostridium gram-positive or gram-negative?
   gram positive

2. What are the oxygen requirements of Clostridium? anaerobe

3. What shape does Clostridium demonstrate?
   endo-sporE forming

4. Where can Clostridium be found?
   soil contaminated with animal poo

5. What is the function of the endospore? resistance to harsh conditions

6. What type of toxin does Clostridium release? exotoxin (neuro toxin

7. What disease does Clostridium tetani cause? lock Jaw and botulism

   Domain: Archaea

   1. What are the three groups in this domain and what characteristics are used to separate them?
      Methanogens (methane releasing ), halophiles (live in high salt areas), Thermophiles (Extreme temperatures)

   2. What types of cells make up these organisms?

      Prokaryotic cells

   3. What characteristics do these organisms have in common with eukaryotes?

   DNA intron present

   start amino Acid for protein synthesis

   RNA poly merase

   Response to anti biotics

   4. What are these organisms most closely related to?

   eukaryotes

   5. Know the example slide for this domain

   Viruses Are Made of genomes enclosed in a protective coat (capsid).

8. What are the 6 different forms of Nucleic acid found in viruses.

   6 Different forms of nucleic acid

   • dsDNA

   • ssDNA

   • dsRNA

   • ssRNA that serves as mRNA

   • ssRNA That is a template for mRNA

   • ssRNA that serves as a template for DNA synthesis

   Size

   -Smallest virus in at 20mm (smaller than a ribosomes)

   Reproduction of virus

   Lytic cycle destroys the cell, Lysogenic cycle is dormant, no immediate harm