BIO41 Exam1

the study of microscopic organisms (microbes)

simple cells, protozoa, algae, fungi, helminths, viruses

defining groups of biological organisms on the basis of shared characteristics and giving names to those groups

Carl Linnaeus

Manual of Systemic Bacteriology-main resource for determining the identity of bacteria species, utilizing every characterizing aspect

• 1) Monera
• 2) Protista
• 3) Animalia
• 4) Plantae
• 5) Fungi

common characteristics

Monera

Monera, Protista, Fungi 

• 1) Eukarya
• 2) Archaea
• 3) Bacteria

Eukarya 

DNA sequencing revealed 3 the domains arose separately

Genus + species

4.5 billion years

3.5 billion years

2 billion years

• 1) toxin production
• 2) structural modifications
• 3) metabolic modifications

hospital-acquired infection

the competition between normal microbes and pathogens for nutrients and space

first discovered the bacterial world

1st to trace a disease to a bacterium

• pioneer in antisepsis;
• had med students wash hands with chlorinated water

Late 1800s

• 1) Pathogen must be found only in abundance in sick
• 2) Must be isolated and grown in pure culture
• 3) Should cause disease when introduced to healthy organism
• 4) Must be reisolated and reidentified as identical pathogen

-establish a causal relationship between a causative microbe and a disease

disease is caused by a specific pathogen/germ

an emanation from rotting organic matter that caused disease

• 1) Spontaneous fermentation occurs (rejected)
• 2) Air ferments grape juice (rejected)
• 3) Bacteria ferment grape juice into alcohol (modifed)
• 4) Yeasts ferment grape juice into alcohol (accepted)

• 1) observation leads to a question
• 2) hypothesis generated
• 3) design/conduct experiment
• 4) accept/reject/modify hypothesis based on observed results from experiment

8-50µm vs 1µm

individually enclosed organelles

• Similar: phospholipid bilayer, glycoproteins
• Different: prok enclosed in cell wall, most metabolic processes done here

has 2 phospholipid bilayers with nuclear pores that allow transcription factors and RNA in/out

more densely packed/stained region in the nucleus where RNA is synthesized/transcribed

• threadlike mass of DNA associated with special proteins
• called histones that play a role in packaging nuclear DNA

prokaryotes don't have chromatin (supercoiled)

nuclear division resulting in 2 identical cells with the same amount of DNA

in eukaryotes only

nuclear division partitioning chromatids into 4 nuclei with half the amount of non-identical DNA 

necessary for sexual reproduction

internal network of fibers maintaining a cell's basic form

also used for movement in some bacterial cells

found in prok's and euk's

functions in aerobic ATP production

has 2 phospholipid bilayers, with inner membrane folded into numerous cristae that increase surface area

found only in euk's

function in photosynthesis - gather light energy to produce ATP and form sugar from CO₂

found in only in photosynthetic eukaryotes

forms proteins during translation

• prok: 70S (30S + 50S)
• euk: 80S (40S + 60S)

lipid/steroid synthesis

detox in hepatocytes

• has ribosomes attached
• ribosomes make protein & collect in ET to be delivered to Golgi

modifies, sorts, targets proteins

breakdown of unwanted intracellular material

• oxidizes amino acids (long chain FA's)
• keeps byproducts of photosynthesis from building up in plants
• contain peroxide

• large, long-term storage compartments
• store water, salts, fat, glycogen, starches, etc

plants, algae, fungi, some protozoa

made of cellulose, chitin, polysaccharides 

cell wall

• 1) cocci
• 2) bacilli
• 3) vibrio
• 4) spirilla
• 5) spirochete
• 6) pleimorphic

70% water

• diplo
• strepto
• v-shape
• palisade (bacilla stacked)
• tetrad (4 in square)
• sarcinae (8 in cube)
• staphylo
• filamentous

• proteins
• polysaccharides
• DNA
• phospholipids

make up 26% of cell

• structural protection
• adjust to salinity changes
• identification

peptidoglycan

• axis 1: alternating sugars NAM & NAG
• axis 2&3: tetrapeptide & glycine chain crossbridges

• (+): thicker layer of peptidoglycan & teichoic acid
• (-): think layer of PTG; external, additional bilayer w/ outer leaflet made of LPS

part of external layer of cell wall

• 1) Lipid A
• 2) core sugar
• 3) variable O (sugar) side chain

has thick wall like Gram(+) but made of waxy substance called mycolic acid

• secreted by bacteria to help them
• 1) stick to surfaces
• 2) resist being recognized/engulfed by phagocytes
• usually viscous polysaccharide

aggregate of microbes in a sticky material to adhere to surfaces

"live coating of bacteria"

• protein extensions of bacterial cells
• contain protein @ end to attach to specific targets
• pili if few, fimbriae if many

• 1) methanogens
• 2) halophiles
• 3) thermoacidophiles

all chemical reactions in an organism

breakdown of larger molecules into smaller ones

use light as energy source

acquire energy from redox rxns of in/organic chemicals

utilize inorganic C as sole source of C

catabolize reduced organic molecules they acquire from other organisms

energy from light, C from eating other organisms

energy from chemical compounds, C from CO2 (inorganic C)

methanogens

energy from light, C from CO2

trees

energy from chemical compounds, C from organic compounds

most animals, fungi

combination of cofactor and apoenzyme

• heat,
• pH,
• oxidation,
• mechanical agitation,
• enyzme/subtrate concentrations
• inhibition

• competitive inhibitors bloc active sites;
• non attach to allosteric site, altering active site