Lecture 7-12 Flashcards
What is the oldest group of bacteria
Firmicutes
______ allow the bacterium to survive environmental stress-it is a dormant and strong structure
Endospores
______ is used to make holes in cheese
Streptococcus thermophilus
What bacteria is involved with botox and also has another clinical functions?
Clostridium botulinum
Hyperhidrosis
______ are believed to be responsible for increasing oxygen concentrations on Earth 3000-2700 Mya
cyanobacteria
How do cyanobacteria grow in water?
Industrial and Agricultural waste in lake leads to an increase in phosphorus and nitrogen, cyanobacteria grow
Organisms underneath the surface of water can’t get enough sunlight and oxygen
What is an example of a cyanobacteria?
Nostoc pruniforme
______ are the most recently diverged group of bacteria according to molecular phylogenies
Proteobacteria
_____ are nitrogen fixing bacteria.
Rhizobium
_____ contain a compartment bound nucleus and contain membrane bound organelles.
Eukaryotes
What is a characteristic of nemertea?
Not venomous, use mimicry
What is a characteristic about nematoda?
Require, some kind of moist, aqueous environment
Nematoda infection coffee and cacao plants, may result in an increase in price
____ were the first group of plants to leave wet environment
Bryophytes
_____ plants make cones and _____ plants make flowers
Gymnosperms, angiosperms
How do horsetail plants protect themselves?
rings of silica, used to protect against animals eating it
In regards to the gymnosperm ginkgo, why should you plant male?
females fruit when opens smells rancid
_____ help cows digest plant matter but also is wiping out large population of frogs around the world
Chytrids
______ is found on spoiled food
Zygomycota
______ form symbiotic relation with plants, mycorrhizae, trade water with phosphorus (rhizobia is nitrogen and water)
Glomeromycota
_____ are black truffles, very expensive
Ascomycota
____ are general mushrooms we associate ourselves with (the cap is the fruiting body)
Basidiomycota
What came first plants animal or fungi?
plants, fungi and animals are more closely related
______ are thought to be the sister group (most closely related) to animals based on what 2 characteristics?
Choanoflagellates
Choanoflagellates have similarities with the feeding cells of sponges
Sequenced genome contains proteins previously found only in animals (adherens and clathrins) that are required for cell adhesion
_____ is green algae and ______ is red algae
Chlorophyta, Rhodophyta
______ is a thickening agent involved in agar plates, chocolate milk and fruit gushers
Rhodophyta
What are the two theories to the origin of eukaryotes?
Simple to Complex
(Haeckel, 1866)
Eukaryotes came from simpler prokaryotes through increasing complexity
Reductive Process (Reanney, 1974) Eukaryotes are ancestral and prokaryotes arose through a reductive process
True or False: The nucleus has a double membrane.
True
True or False: Organelle structures are not separate from each throughout the rest of the cell
True
What are the 4 theories of the origin of the nucleus?
Syntrophy model Proto-eukaryotic cells evolved from eubacteria Viral Eukaryogenesis (Bell, 2001) Endomembranes came from inbudding of plasma membrane (Jekely, 2007)
What is the syntrophy model?
Two different cell types: black cells, white cells
– Something black cells were making (waste), highly attractive to white cells
White cells use the black cells waste and surround black cell
Black cell increases the surface area of contact to be able to maximize waste excretion and pickup
White cells merged together along the perimeter to form one type of cell on the outside
Merging becomes permanent, syntropy happens where both cells benefit from each other
What are the two evidences that support the syntrophy model?
Eukaryotic genome organization and dynamics and DNA processing systems are the same in Archaea
Genes for social, developmental, and metabolic pathways and processes are more similar to those of eubacteria
What is the Proto-eukaryotic cells evolved from eubacteria model?
DNA is inside second membrane that contains DNA
- ”nucleus”
What are two evidences that support the Proto-eukaryotic cells evolved from eubacteria model?
Some Planctomycete bacteria contain a double membrane around their DNA
Some Planctomycete bacteria contain condensed DNA
What is the Viral Eukaryogenesis model?
A primitive DNA virus (a bacteriophage ancestor) gets trapped within an RNA cell and becomes a primitive nucleus.
Cellular genes are progressively recruited to the enlarging nucleus because of the selective advantages of DNA biochemistry.
For a while this situation remains unstable and reversible, allowing new ‘pre-eukaryotic viruses’ to be created. These viruses reinfect other cells at various stages of this iterative process.
What are the two evidences that support Viral Eukaryogenesis model?
Several features of the eukaryotic nucleus resemble those of viruses: mRNA capping, linear chromosomes, separation of transcription from translation
Viral contribution allowed the cell to start phagocytosis and become a predator
What are the two evidences that support the endomembranes came from inbudding of plasma membrane model?
Common ancestry of nuclear pore complexes and vesicle coating complexes
RAN-GTPases needed to anchor chromatin in the nucleus are related to membrane-trafficking small GTPases found in all eukaryotes
How does DNA structure differ from prokaryote to eukaryote?
circular origin of replication bacteria, linear telomere eukaryote
_______ is causes lyme disease.
Borrelia burgdorferi
Increase in acorns = increase in deer mice = increase in deer ticks
How does bacterial DNA condensate?
SUpercoiling to form smaller structure
How does eukaryotic DNA condensate?
nucleosome - histone proteins, wrap DNA and compactly store it
True or False: Prokaryotes have the least amount of non-protein coding sequences.
True
True or False: Introns are coding sequences.
False, exons are
What is the difference between gene organization within prokaryotes and eukaryotes?
Prokaryotes - Always get the same thing, limited options
Eukaryotes - Alternative transcripts, can have some flexibility in the system (ie, pizza analogy)
What are the characteristics of eukaryotic DNA structure?
Multiple, linear chromosomes
Chromosomes are condensed by histones and surrounded by nucleus
Two or more copies of each gene (diploid, etc.)
Genomes contain large amounts of non-coding and repetitive DNA
Plasmids usually absent
Operons often absent
What are the characteristics of prokaryotic DNA structure?
Single, circular chromosome
Chromosomes are condensed by DNA supercoiling in the nucleoid
One copy of each gene (haploid)
Genomes are compact and contain little repetitive DNA
Plasmids often present
Operons often present
What are the differences in transcription and translation?
Compartmentalization
RNA modifications-RNA splicing, 5’ end capping, and addition of poly-A tail
prokaryote, all in one compartment, eukaryotic in separate compartments
Why might these differences in DNA characteristics and dynamics exist?
Prokaryotes = smaller, shorter life, rapidly reproduce
- circular DNA, operon, used for fast replication of DNA or amino acid - supercoiling condensation quicker then having to require histones - one copy of gene = greater risk of copy error, but short lived organism produces fats good trade off, eukaryotic can’t afford error (that’s why haploid) b/c live long
