Exam 1 Flashcards
Scientific Method
Observation Question Hypothesis Test the Hypothesis Does the Data Support the Hypothesis? Modify Repeat
Fungi
Plant-like: Cell walls
Animal-like: Obtain energy and nutrients from other organisms
Molds
Hyphae
Multi-cellular
Spread / reproduce with spores
Yeast
Unicellular
Reproduce by budding
Protists (protozoa)
Unicellular
Animal-like: Obtain energy and nutrients from other organisms
Can move via structures
Algae
Can be uni or multicellular
photosynthesize
Bacteria
Unicellular with many configurations: Rods, Cocci, Spirochetes
Archaea
Unicellular: Similar to bacteria, but extreme shapes and places
Viruses
Not living, do not fit into the tree of life
Differences between Prokaryotes and Eukaryotes
Prokaryotes: 1um long, 70s ribosomes
Eukaryotes: 10-100um, have membrane bound organelles, 80s ribosomes
Different types of cell walls
Fungi: Chitin
Bacteria: peptidoglycan
What is the shape of chromosomes in Bacteria and Archaea?
Circular
Out of Billions of bacteria species, about how many are responsible for making us sick?
30ish
Microbial Infallibility
For every naturally occurring compound there is a microorganism that can decompose it.
Plastics are derived from _____ which is in turn derived from _____.
Petrochemicals, oil
Plastics can be deteriorated without microorganisms but can only be broken down so far.
Physical degradation
Plastics can be broken down about as far as a jelly-like substance
Microorganism timeline
Earth formed 4.6 bya First microorganisms 3.5 bya O2 available in significant amounts 2.5 bya First Eukaryote 1.7 bya Multicellular Eukaryote 1 bya Dinosaurs .045 bya
How many Bacteria and Viruses are assumed to exist?
Bacteria: 5x10^30
Viruses: 1x10^32
Biological Nomenclature
Domain Kingdom Phylum Class Order Family Genus Species
Numerical Taxonomy
Name based on trait similarity Disadvantages 1) Trait choice 2) All traits 3) Some traits 4) Same trait
Phylogenetics
Based on similarity of Gene Sequences
Sequences must be found in all representatives of the group studies
Functions must be same in all representatives
Sufficient differences such that each sequence has it’s own signature
Naming by Disease
Pathogenic species are named based on the disease they cause
Macromolecules
Polysaccharides, Phospholipids, Nucleic Acids, Proteins
Polysaccharides
Carbohydrate (hydrated carbons): glucose or ribose.
Energy Source, Structure, Information
The difference between sucrose and high fructose corn syrup?
HFS doesn’t have a oxygen bridge between the two ring structures.
Xanthan Gum
Polysaccharides with a seemingly complicated structure composed mostly of glucose.
Produced by Xanthomonas campestris
Capsule
Prevent a microorganism from drying out and attach it to the host.
Proteins
Have very complex structures / shapes that determine function.
Proteins are polymers (chains of amino acids)
Function as enzymes and structure
Amino Acids
All have the same basic structure, but differ in their R groups.
Making a peptide bond
NH2 and COOH groups bond, the each drop a H and OH respectively (which goes to water) and form a polypeptide linkage. r-C-N-r with =O from the C
(Very Strong)
Nucleic Acids
Named Nucleic Acids because they were isolated from the nucleus
RNA and DNA (“de-oxy”)
Information, Structure, and Energy
DNA bases
Adenine
Guanine
Thymine
Cytosine
A always bonds T
C always bonds G
RNA bases
Adenine
Guanine
Uracil
Cytosine
Lipids
Primary component of the cell membrane
Phospholipids
Carry two fatty acid chains linked together by glycerol, and phosphate
Amphipathic
Peptidoglycan
Polysaccharides of NAG and NAM, proteins link these together
What are the two cell architectures?
Gram + and -
+: Rigid, thick external wall protects the cell membrane from osmotic pressure
Teichoic acids: protect the cell membrane from chemicals
-: Equally sized layers
Porin: channel through the outer membrane
Lipopolysaccharide(LPS): Barrier against chemicals
The Gram Stain
1: Crystal violet purple dye
2: Iodine (mordant)
3: Alcohol wash (decolorization)
4: Safranin (counterstain)
Cytoplasm
70% water
No empty space and very little free water
Wide variety of proteins and chemicals
Nucleoid (prokaryotes)
A region of the cell that contains the singular, circular chromosome.
Endospores (prokaryotes)
Only some bacteria make these Contains a copy of the chromosome Endospores are dormant 1) Extremely low water content 2) Dormant (1000’s of years?) 3) DNA is tightly compacted 4) Highly resistant
Ribosomes
75% of the cells dry mass
Ribosomes translate (express)
the messages sent from genes
into new proteins
Endoplasmic Reticulum
Cell transport system
Golgi Bodies
Packages molecules for secretion in Secretory Vessicles
Other internal vesicles (Lysozomes) carry digestive enzymes to process food
Why do mitochondria and chloroplasts have bacterial properties?
Over time, the cells lost the ability to survive independently Endosymbiotic Theory suggests that this was the origin of eukaryotes
1, 2, 3 troph
1) Energy source (Chemo / photo) [ATP]
2) Electron Source (organo / litho [inorganic]) [NADH]
3) Carbon Source (Hetero [organic chemicals], Auto [CO2])
ex: Chemolithoautotroph (get energy and electrons from inorganic chemicals (weird)
Conditions influencing Bacterial Growth
Temperature
Osmolarity
Oxygen
Acidity
Thermophiles and Hyperthermophiles
Survival is based on:
Thermostable proteins fold at high temps
and membranes with saturated fatty acids
Psychrophiles
4 to 10 degrees C
Optimized for low temps, membranes have unsaturated fatty acids
Hal(o)-
salt
Halophiles
Halobacterium and the Saltern
Microbacterial protection from O2
Superoxide Dismutase (enzyme that detoxifies radicals) makes H2O2 which is toxic in high amounts. Catalase converts that to water
