( UNIT 03 ) Domain & Kingdoms & Phylums Flashcards
What are the 3 domains?
- Domain Bacteria
- Domain Archaea
- Domain Eukarya
Domain Bacteria
- Prokaryotes
- Peptidoglycan cell walls
- Some Aerobic or Anaerobic
- Some Autotrophic , Most Heterotrophic
Domain Archaea
- Prokaryotes ( ancient bacteria but more closely related to eukarya )
- Cells walls DON’T contain Peptidoglycan
- Some autotrophic ; Most heterotrophic
Domain Eukarya
- Eukaryotes
- Cell Walls vary within each of the 4 kingdoms ( Protista, Fungi, Plantae, Animalia )
- Fungi + Animalia : heterotrophic
- Protista + Plantae : autorophs
Briefly describe the three groups of Domain Archaea
(all to the extreme!!!)
- Thermoacidophiles : Hot + Acidic environments
- Halophiles : Salty environments
- Mathanogens : Obligate Anaerobes (can’t live in the presence of oxygen
Difference in the cells walls of Domain Bacteria and Archaea ?
Bacteria contains Peptidoglycan; Archaea does not.
Plasmid
A small circular piece of DNA found in many Prokaryotes.
Capsules
A secreted layer of polysaccharides around the cell walls of prokaryotes that prevent is from drying out or being attacked by white blood cells and antibiotics.
Pilli
Hair-like structures made out of protein that help bacteria attach to surfaces.
Cocci
Spherical prokaryotes.
Bacilli
Rod-shaped prokaryotes.
Spirilli
Spiral shaped prokaryotes.
List the basic steps of Gram Staining (which stains are used and in what order)?
- Sterilize inoculation loop
- Fix slide
(Add chemicals in this order) - Crystal Violet (stains purple)
- Gram’s Iodine
- Alcohol Solution
- Safranin
What colour is Gram Positive ?
Purple.
What colour is Gram Negative?
Pink.
Binary Fission
- Asexual Reproduction
- Cell divides into two genetically identical cells
Conjugation
- Sexual Reproduction
- 2 prokaryotes attach and exchange genetic information
- Good to increase genetic diversity
Name the 8 different ways Prokaryotes can gain energy.
- Anaerobic
- Obligate Anaerobes
- Facultative Anaerobes
- Obligate Aerobes
- Heterotrophs
- Saprotrophs
- Photoautotrophs
- Chemoautotrophs
Anaerobic
Doesn’t use oxygen for growth / metabolism.
Obligate Anaerobes
Can’t live/grow in the presence of oxygen.
Facultative Anaerobes
Can grow both in the presence of oxygen or without it.
Heterotrophs
Must consume other organisms for food/energy.
Saprotrophs
Heterotrophic bacteria; can’t photosynthesize own food.
Photoautotrophs
Uses light to produce food for energy.
Chemoautotrophs
Doesn’t require light for energy.
Endospore
- A structure produced by bacteria due to harsh conditions
- Like a dormant cell
- When conditions improve endospore grows/germinates into a new bacterial cell
How can bacteria be helpful to humans and the environment ?
- Humans : Competes with harmful bacteria to prevent them from causing disease ( E. Coli in us makes vitamin K )
- Environment : Helps cycle nutrients and Nitrogen Fixation
What are 2 ways a bacteria can cause disease?
- Multiply quick in the site of infection before bodies defense system can destroy them
- They can secrete a toxin/other substances that might cause harm
Describe the structure of a virus.
A non-living strand of genetic material within a protein coat.
Why are viruses not considered alive?
They lack many of the characteristics of life (e.g., don’t maintain homeostasis, not made out of cells, aren’t made out of cells, don’t require energy, etc.)
Lytic cycle
- Host cell reproduces more viral capsids and enzymes. Viruses leave by bursting or by releasing new viruses that infect more cells (lyse).
- Active Infection: Infection shows immediate symptoms (1-4 days)
Lysogenic Cycle
Viral replication cycle where the viral DNA integrates into the host cell and remains dormant until triggered to enter the lytic cycle.
Retrovirus
- Made of RNA instead of DNA
Prions
Misfiled protein that causes diseases.
