Lecture 5: Biodiversity part 1 Flashcards
What is taxonomy?
science of classifying living things
What is the order of hierarchical classification?
-domain
-kingdom
-phylum
-class
-order
-family
-genus
-species
What is the domain model of bacteria?
-unicellular
-no nucleus
-prokaryote
What is the domain model of Archaea?
-unicellular
-no nucleus
-prokaryote
What are things that a eukaryote has that prokaryote don’t?
-membrane bound nucleus
-membrane bound organelles
-gene expression are different
-DNA is arranged on chromosomes
What is the domain model of Eukarya?
-unicellular/multicellular
-nucleus
-eukaryote
What are the advantages of a peptoglycan cell wall?
-maintains the shape
-whitstands hypotonic environments
What are the characteristics of Gram-positive Bacteria?
-simpler walls
-large amount of peptoglycan
-stain color purple
What are the characteristics of Gram-negative Bacteria?
-less peptoglycan
-outer membrane can be toxic
-MORE likely to be antibiotic resistance
-stain look pink
How do antibiotics act on bacteria?
target peptoglycan + damage bacteria cell wall
What are two key activities in nutrients cycling in bacteria?
-decomposition
-Fixation
What does decomposition in the nutrients cycling?
release nutrients from decaying organisms into the environment for re-use
What does fixation in the nutrient cycling?
return nutrients from oxidized inorganic forms to reduced organic forms
What means pathogenic?
bacteria that can causes diseases
Explain why Escherichia Coli is virulent and considered to be pathogenic?
-virulence strains depends upon the length of the genome + toxicity of the resulting protein
What are the 3 basics shapes of bacteria?
-rod-shaped
-spherical
-helical-shaped
Define the mode of nutrition heterotrophs
*Bacteria that feed themselves on other organisms for obtaining their energy
Define photoautotroph
when using light energy from the sun
Define chemoautotroph
derive energy needed from inorganic molecules to produce food in the form of carbohydrates
What are the 4 mains characteristics of proteobacteria?
-gram negative
-photoautotroph
-chemoautotroph
-heterotrophs
Give an example of a proteobacteria
Escherichia Coli
What is the chlamydia bacteria?
parasites that live within animals cells
Define spirochetes
-helical heterotrophs
Define cyanobacteria
-gram negative
-photoautotrophs
*plant chloroplast likely evolved from cyanobacteria by endosymbiosis
What does heterocyst means?
cells specialized to fix nitrogen
What is the particularity of the Nostoc cyanobacteria?
genus of cyanobacteria that is common in a variety of habitats
What are 3 characteristics of Gram positive bacteria?
-largely solitary
-form endospores: metabolically inactive
-anarobic – DON’T need oxygen
What are the two fundamental characteristics of the domain archaea?
-unicellular
-mostly anaerobic
How does Archaea differs significantly from bacteria? (5)
-Plasma membrane structure (made of different types of lipids)
-Cell wall
-DNA replication
-RNA ribosomes in Archaea similar to those in Eukaryote
-Gene expression
Name the main difference in the cell wall between Archaea and Bacteria?
Bacteria: made of peptoglycan
-Archaea: lots of variability, NO peptoglycan
What are the 3 main categories of Archaea?
-Methanogens
-Extremophiles
-Nonextreme archaea
How many supergroup Eukarya has?
6
What are the 3 main domains of eukaryotes that we will analyse?
-plantae
-animalia
-fungi
++ protists
What is the nutrient mode of the kingdom plantae?
photoautotrophs: produce their own sugar by photosynthesis
What is the nutrient mode of the kingdom Fungi?
absorptive heterotrophs: absorb dissolved nutrients from surrounding
What is the nutrient mode of the kingdom Animalia?
heterotrophs: obtain food by eating and digesting other organisms
What is the 3 nutrient mode of protists?
-heterotrophs
-autotrophs
-mixotrophs
Which supergroup do the 3 min Eukarya kingdom belong in?
opisthokonta
What is a monophyletic group?
group of related species – complete branch on the tree life
What is a paraphyletic group?
-not all descendants of a single common ancestor
How does protist photoautotroph nourish?
by containing chloroplast
How does protist heterotrophs nourish?
-absorb organic molecules
-ingest larger food particles
What is an example of a protist in the supergroup Excavata?
