Biology 2 Practicum I (lab 1)

Prokaryotic cell characteristics

Singular circular chromosomes. Ribosomes (70s). Peptidoglycan cell wall. No membrane-bound organelles.

First prokaryote appearance fossil record

3.5 billion years ago

What form did the fossil prokaryote fossil take?

Fossilized stromatolites

How long were prokaryotes on earth by themselves?

1.4 billion years

Where are prokaryotes found?

Most habitats on the planet

What is the part covered in DARK GREEN called?

Fimbriae

What is the part covered in YELLOW called?

Nucleoid

What is the part covered in PURPLE called?

Ribosomes

What is the part covered in PINK called?

Plasma Membrane

What is the part covered in BLUE called?

Cell Wall

What is the part covered in ORANGE called?

Capsule

What is the part covered in LIGHT GREEN called?

Flagella

What is the part covered in RED called?

Bacterial Chromosome

What is the shape of this bacteria?

Coccus

What shape is this bacteria?

Bacillus (rod)

What shape is this bacteria?

Helical

What shape is this bacteria?

Filamentous

What do the cell walls of prokaryotes contain?

Peptidoglycan

What is the structure of the cell wall in gram-positive bacteria?

A simple structure with large amounts of peptidoglycan that retains the violet color

What color does gram-positive stain?

violet

What is the structure of the cell wall in gram-negative bacteria?

Small amounts of peptidoglycan in between two membranes.

What color does gram-negative stain?

red

What gram stain is this?

Gram-positive

What gram stain is this?

Gram-negative

What are these?

Bacterial Colonies

What characteristics allow antibiotics to work on bacterial cells without affecting eukaryotic cells?

The presence or absence of cell walls, ribosome structure and different metabolism.

Antibiotics work differently on different bacterial colonies.

True

It is possible to have one antibiotic that would fight all bacterial infections.

False

What is a narrow spectrum antibiotic?

works on EITHER gram-negative or gram-positive bacteria

What is a broad spectrum antibiotic?

Works on BOTH gram-negative and gram-positive

Why are come bacteria pigmented?

Because of photosynthesis and UV protection.

What is the name of the YELLOW bacteria?

Micrococcus Luteus

What is the name of the RED/BROWN bacteria?

Serratia Marcescens

Where can luminescent bacteria be found?

Deep seas and in soils

What enzyme do these species have that allows them to give off light?

Luciferase

What re some of the industrial application these bacteria serve?

They tract plant infection progression, antibiotics in milk, toxic pollutants in the environment and dangerous bacteria in food.

What did Carl Woese use to separate the kingdom Monera into different domains?

Molecular Biology

What are the major groups included in the Domain Bacteria

Proteobacteria

The Chlamydias

The Spirochetes

The Cyanobacteria

The Gram-positive bacteria

What were the first Archea called?

Extremophiles

What were the two types of Archea?

The halophiles and the thermophiles

What is the name of the group in the more moderate environments?

Methanogens

What technique do scientist use to determine classification of microorganisms?

Taxonomy

What test do scientist use to analyze microorganism genes?

PCR (polymerase chain reaction)

What ability does bacteria have that make classification difficult?

Horizontal gene transfers

What is the average % of the bacterial genome made by this process?

75%

What phenotypic typing schemes do clinicians and clinical microbiologists rely on for identifying bacterial species?

Bacterial morphology

Staining properties of the organism

O2 growth requirements of the species

What group is this?

Proteobacteria

How is that group divided into subgroups?

Photoautotrophic

Chemoautotrophic

Chemoheterotrophic

This is E.Coli. Is it gram-positive or gram-negative?

Gram-negative

What are the oxygen requirements of E.coli?

Facultative anaerobe

What shaped does E.coli demonstrate?

Rod-shaped

Where can E.coli be found in humans?

The Intestinal tract

What structure do some of the pathogenic stains have?

Fimbrae

What are the causes of outbreaks of E.coli in the U.S.?

Raw milk or undercooked hamburger

What group is this?

Chlamydias

What shape do these organisms demonstrate?

Coccus shape

Where are these organisms found? (chlamydias)

Intracellular parasites of animals

How are these organisms transmitted?

Interpersonal contact or airborne respiratory routes.

Is this group gram-positive or gram-negative? (e. coli)

gram-negative

What is lacking in the cell wall of this group? (chlamydias)

Peptidoglycan

What is an example of the group Chlamydia?

Chlamydia trachomatis

What are two problems associated with Chlamydia Trachomatis?

Blindness

STI (sexually transmitted infection)

What group is this?

Spirochetes

What shape do these organisms demonstrate?

Helical chemoheterotrophs

What are the nutritional requirements for this organism?

Anaerobe

What is the name of the special structure involved in this group’s movement?

Fibrils

Where can the spirochete group be found?

Aquatic environments

Animals bodies

What is this organism?

Treponema Pallidum

What disease does this organism cause?

Syphilis

What are the four stages and symptoms of this disease?

Stage 1: Chancre (red, painless sore). 3-6 weeks

Stage 2: Rash that doesn’t itch. 1-6 months

Stage 3: No external symptoms. Months-lifetime.

Stage 4: Permanent damage to viral organs and death

How is this disease transmitted?

Sexual intercourse, kissing, or other intimate body contact.

What are the requirement for transmission? (spirochetes)

Warm, moist skin or mucous membrane surfaces.

What are this organism oxygen requirements?

Anaerobic

What group does this organism belong to?

Cyanobacteria

What are this groups nutritional requirements? (cyanobacteria)

Photoautotrophic bacteria

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

Aerobic or anaerobic

What is the name of the pigment that gives the bacteria in this group their blue-green color?

Phycocyanin

What two processes are found together only in this group of organisms?

Release oxygen and fix nitrogen

What is this organism?

Oscillatoria

Where can Oscillatoria be found?

Fresh water

What shape does Oscillatoria demonstrate?

Filamentous

What causes Oscillatoria to go through a “bloom”?

Phosphates in detergent

What is the eventual outcome of these “blooms”?

Oxygen is removed from water; death of organisms

What group does this organism belong to?

Gram-positive bacteria

What type of Gram stain do most of the bacteria in this group demonstrate? (chlamydias)

Gram-positive

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

Chemoheterotrophs

What organism is this?

Clostridium tetani

Is Clostridium gram-positive or gram-negative?

Gram-positive

What are the oxygen requirements of Clostridium?

Obligate anaerobe

What shape does Clostridium demonstrate?

Rod-shaped

Where can Clostridium be found?

Soil with animal fecal waste

What is the function of the endospore?

Make the bacteria resistant to harsh conditions

What type of toxin does Clostridium release

Exotoxin

What disease does Clostridium tetani cause?

Lockjaw and botulism

What are the three groups in the prokaryote domain, and how are they separated?

Methanogens: methane-releasing

Halophiles: live in high-salt areas

Thermophiles: live in extreme temperatures

What types of cells make up these organisms?

prokaryotic cells

What characteristics do these organisms have in common with eukaryotes?

• DNA introns present

• RNA polymerase

• Start amino acid for proteins

• Response to antibiotics

What are these organisms most closely related to?

Eukaryotes

Name an example of Archea

What are viruses made up of?

Genomes (DNA or RNA) enclosed in a protective coat called capsid.