Flashcards in Diversity of Microorganisms Deck (73):
Microorganisms can be classified according to their...
Nutritional pattern - metabolic diversity
What do phototrophs use as their source of energy?
What do chemotrophs use as their source of energy?
Oxidation of matter
What do autotrophs use as their source of carbon?
Inorganic - carbon dioxide
What do heterotrophs use as their source of carbon?
What does anabolic mean?
Anabolic - build up to make more complex molecules
What does catabolic mean?
Break down molecules to smaller molecules
What microbes are normally in the chemoautotroph division?
Bacteria and archaea living in hostile environments
What is the source of energy for chemoautotrophs?
Chemical - inorganic compounds such as hydrogen sulphide, or ferrous iron
How is energy produced for chemoautotrophs?
Electrons are captured from inorganic compounds such as iron and passed along the ETC, ATP produced
What is the energy produced used for by chemoautotrophs?
To reduce co2 to make complex carbon molecules
What are complex carbon molecules?
Carbohydrates, fats, proteins
What is ferrous iron converted do and by which bacteria?
Ferric iron acidithiobaciullus ferrooxidans
What is sulphur converted to and by which bacteria?
Sulphuric acid - acidithiobacillus ferooxidans
What microbes are normally in the chemoheterotroph group?
Include fungi, protozoa and most bacteria
What do chemoheterotrophs use as their source of carbon?
What do chemoheterotrophs use as their energy source?
Chemical - break down carbon
Humans and almost all medically important microbes make up which group?
What microbes are in the photoautotroph category?
Oxygenic - cyanobacteria, anoxygenic - green and purple bacteria
What do photoautotrophs use as their energy source?
What do photoautotrophs use as their carbon source?
What is the energy used for by photoautotrophs?
To fix carbon dioxide to make complex carbon molecules
How do cyanobacteria and green&purple bacteria differ?
Cyanobacteria - oxidise water to oxygen. Green and purple bacteria capture light from pigments to convert hydrogen sulphide into sulphur - primitive
Are photoautotrophs anabolic or catabolic?
What do photoheterotrophs use as their energy source?
What do photoheterotrophs use as their carbon source?
Organic carbon moleules
Examples of photoheterotrophs?
Green and purple sulphur bacteria
Photoheterotrophs are usually...
Are photoheterotrophs anabolic or catabolic?
What is an eukaryotic microbe?
Contains a nucleus and membrane bound organelles
What is a prokaryotic microbe?
Doesn't contain a nucleus or any membrane bound organelles
What is the typical diameter of a cocci prokaryotic cell?
What is the typical length of a rod prokaryotic cell?
What is the difference between a prokaryotic and eukaryotic flagella?
Prokaryotic - simple, consists of two proteins. Eukaryotic - complex, consists of multiple microtubules
Which cell wall when present is chemically complex?
Which plasma membrane has sterols and carbohydrates present that act as receptors?
Eukaryotic cell membranes
How do ribosomes differ in prokaryotes and eukaryotes?
70S in prokaryotes, 80S in eukaryotes
Which cell type has multiple linear chromosomes with histones?
Which cell type contains single circular chromosomes, bacteria lacking histones and archaea have histones?
What is the most abundant group of living organisms?
What are the common shapes of bacteria?
Coccus, rod, spirillum, spirochete, filamentous
Bacteria are uni-
Bacteria divide by
Bacterial cell walls contain
peptidoglycan - a sugar polymer
What is useful about a bacterial cell wall?
Can be stained to classify species
Cell membranes in bacteria are composed of...
Unbranched fatty acid chains attached to glycerol by ester linkages
Individual bacteria may form...
pairs, chains, clusters
What are the three main groups of archaea?
Methanogens, extreme halophiles and extreme thermophiles
What are methanogens?
Archaea - strict anaerobes, produce methane
What are extreme halophiles attracted to?
What are extreme thermophiles attracted to?
Who classified archaea as a distinct grouping?
Archaea are predominantly ...
In archaea, the DNA is associated with
In archaea, the cell wall does not contain
Plasma membranes in archaea are composed of
branched hydrocarbon chains attached to glycerol by ether linkages - different to bacteria
Fungi are part of which group?
Fungi cell walls are made of...
What is a spore?
a spore is a unit of asexual reproduction that may be adapted for dispersal and for survival, often for extended periods of time, in unfavorable conditions - fungi are able to form spores
Which fungi are unicellular?
yeasts such as candida albicans
Is yeast forming spores sexual or asexual?
Is yeast budding sexual or asexual?
Examples of multicellular fungi?
molds and mushrooms
Multicellular yeasts contain mycelia. What are mycelia?
They are composed of long branched filaments called vegetative hyphae
Multicellular fungi reproduce by which mechanisms?
Hyphal fragmentation (asexual), sporangia (asexual) and gametangia (sexual)
Yeast are dimorphic, what does this mean?
They can either grow as mold (mycelium) or yeast (unicellular)
Describe an example of yeast being dimorphic.
Blastomyces dermatitidis survive in soil that contains debris mycelium, infects mammals - unicellular form causes Blastomycosis. Switch at 37 degrees triggers change to yeast like form.
Describe protozoa in two words
free living and parasitic
Protozoa move by
pseudopodia or flagella or cilia
What are the three methods that protozoa can reproduce aseuxally?
Binary fission where one cell can split into two. Schizogony where the nucleus divides many times before the cell divides. Budding where buds form and pinch off of the parent cell.
How can protozoa reproduce sexually?
By the fusion of gametes and some produce cysts
The cell walls of algae contain...