Final Flashcards
What were the three kingdoms Ernst haeckel proposed?
Plantae
Animalia
Protista (unicellular)
What was Herbert copelands four kingdoms?
Plantae
Animalia
Protista (unicellular eukaryotes)
Monera (unicellular prokaryotes)
What did stander do?
Created two domains
Prokaryotes - monera
Eukaryotes - plantae, animalia, and Protista
What did whittaker do?
Added the fungi kingdom based on nutritional differences
Plantae- autotrophs
Animalia - heterotrophs
Fungi - saprotrophs
What did Carl woese do?
Switched from outward appearance to genetic similarity and common ancestry
Divided prokaryotes into two domains: bacteria and archaea
What are the five super groups?
Excavata Chromalveolata Rhizaria Archaeplastida Unikonta
What is the excavata group?
Three monophyletic groups lacking classical mitochondria; 2,4, or more flagella
Ex. Giardia
What is the chromalveolata supergroup?
Two monophyletic groups via secondary endosymbiosis with P/S red algae
Ex. Red tide
What is the rhizaria group?
Three monophyletic groups with threadlike pseudopodia
Ex. Foramins
What is the archaeplastida supergroup?
Three monophyletic clades resulting from primary endosymbiosis cyanobacterium
Ex. Brown and green algae
What is the unikonta supergroup?
Two monophyletic clades: amoebozoans (lobe shaped pseudopodia) and opisthokonts (uni and multicellular single posterior flagellum)
What are the structural factors that explain bacterial high levels of biodiversity?
- Flagellum: half of all prokaryote species capable of taxis
- Fimbriae: hair like appendages that adhere to surfaces, e transfer, and exchange plasmids
- Capsule: polysaccharides - sticky surface that adhere to substrate or other members of the colony
Provides protection from desiccation, extreme T, viruses, and antibiotics - Nucleoid: single, circular chromosome lacking nuclear membrane
- Plasmid: smaller independently replicating strand of DNA
- Ribosomes
What processes create such a high biodiversity in bacteria?
- Rapid reproduction and mutation
2. Genetic recombination: horizontal gene transfer
What are the three types of genetic recombination?
- Transformation: DNA fragments are spliced into nucleoid from the outer environment
- Transduction: viral DNA enters and breaks up bacterial DNA and begins producing viruses with may contain bacteria DNA
- Conjugation: pilus forms between two bacteria and exchange DNA
What is the bacteria cell wall made of?
Outer membrane: lipopolysaccharides
Peptidoglycan layer: sugars and amino acids X-linked
Plasma membrane: glycolipids and glycoproteins
How are gram negative or positive bacteria determined?
Stained with crystal violet and iodine then washed with ethanol
Counter stained with safranin
If it remains pink then gram negative
If it remains purple then gram positive
What is the difference between gram positive and negative bacteria?
Gram negative: have outer membrane and toxins can cause fever/shock. More resistant to antibiotics
Gram positive: no outer membrane and thicker peptidoglycan. Susceptible to penicillin as it prevents X-linking
Describe the evolutionary reasoning for bacteria colouring
Purple silver bacteria had no competition and optimized light absorption in green/yellow light, reflecting purple
Cyanobacteria capitalized on remaining spectrum and evolved chloroplasts reflecting green
World gradually became oxygenated and killed off most purple sulfer bacteria
Remain green to this day
What are the carbon and energy source of the four Metabolic bacteria types?
Photoautotroph: inorganic CO2, HCO3, energy from sun
Chemoautotrophs: inorganic CO2, HCO3, energy from oxidation of H2S, NH3, Fe2+
Photo heterotrophs: organic C, sun
Chemoheterotrophs: organic C, oxidation of organic compounds
What are the four types are archaea?
Crenarchaeota
Korarchaeota
Nanoarchaeota
Euryarchaeota
What are viruses not considered living?
Can not reproduce on their own
Lack metabolic processes
Do not have cytoplasm enclosed by plasma membrane
What is a virus?
Small bit of nucleic acid covered by a protein cost
Genes encode for protein subunits and transcription
What is a viroid?
Naked circular RNA
What is a prion?
Irregular folded proteins
What are the two general structures and the two modifications of viruses?
Structures:
Helical and icosahedral
Modifications:
Envelope or complex
Describe the lytic cycle
Virus recognizes receptors on host cell and attaches
Injects DNA and creates mRNA to make DNAases which cut up bacterial DNA
Use nucleotides from broken DNA to amplify mRNA and protein synthesis
Creates virus parts and then assemble
Cell lysis and virus leaves
Describe the lysogenic cycle
Virus attaches and injects DNA which splices into host DNA - prophage
Cell divides and replicates with viral DNA - lysogenic stage
Environmental stimuli causes viral DNA to become active
How does retrovirus (HIV) replicate?
Virus has membrane coat that fuses with membrane coat of t-cell
Virus is pulled into cell and releases two RNA strand and proteins
Reverse transcriptase goes from mRNA to single DNA strand and then double
Integrase splices it into host DNA
Causes cell to build protein subunits and then buds off cell membrane and forms final virus
What don’t drugs work well with HIV?
Reverse transcriptase has no spell check so errors cause a slightly different protein and virus each time
What was Carolus Linnaeus’s foundation for biological nomenclature?
Two kingdoms
Regnum Vegetabile
Regnum animalia
What are Protists?
Remnants of an outdated classification system
Today they do not have much in common except they are eukaryotic unicellular or eukaryotic multicellular without specialized tissues
How was the first eukaryotic cell formed?
Outer plasma membrane of arches cell got unfolds and grew around nucleoid forming Golgi apparatus and nuclear membrane
A gram + bacteria was brought into cell and became mitochondria
How many membranes did the 1st heterotrophic eukaryotic cell have?
2
Mitochondrial inner membrane homologous to inner plasma membrane
Chromosome structure homologous to prokaryotes
Reproduces via binary fission
What are diplomonads?
Excavata Nucleus is split into two Mitochondria is greatly reduced and don't make ATP Have flagella Ex. Giardia lamblia
What are parabasalids?
Excavata
Reduced mitochondria produce hydrogen gas
Ex. Trichomonas vaginalis
What are kinetoplastids?
Excavata
Part of euglenozoans
Have one huge mitochondria with 1000s of interlocking DNA strands
Ex. Trypanosoma (African sleeping sickness)
What are the five subgroups of excavata?
Diplomonads Parabasalids Euglenozoans Kinetoplastids Euglenids
What occurred during primary endosymbiosis?
Gram negative bacteria phagocytized and developed a symbiotic relationship with cell producing sugars
Became photosynthetic cell
Lead to evolution of archaeplastids
Have three membranes
What occurred during secondary endosymbiosis?
Phagocytosis of archaeplastid by kinetoplastid developing a symbiotic relationship and producing a euglenid
How were rhodophyta created?
Mutation in an archaeplastida caused it to start producing phycoerythrin an photosynthetic accessory pigment
How were chromalveolata?
Rhodophyta cell was phagocytized into a heterotrophic eukaryotic cell
What are the two phylum sod chromalveolata?
Alveolates and stramenopiles
What groups fall under alveolates?
Diatoms (silica dioxide plates)
Golden algae
Brown algae (kelp)
Oomycetes (fuzz on decomposing fish)