BIOLOGY JUN 11-- EUBACTERIA

shapes of bacteria

bacillus: rod
coccus: sphere
spirillus: spiral
virbrio: boomerane
spirochaetes: tight coils

bacteria arrangement

strepto- chain (str-> string)
staphylo- grape like cluster (sta-> stacked)

bacteria technology 4

food prep
bioremediation
pesticides
bioengineering

Bacteria are____ microorganisms

unicellular

why are bacteria important

vital to nutrient cycles and as decomposers
found in human body
but some are pathogenic

who first observed bacteria

Anton van Leeuwenhoek

who first discovered that bacteria are pathogenic

robert koch and louis pasteur

what was the first antibotic used for and who made it

syphilis
paul ehrlich

evolution of bacteria

thought to be first forms of light 4 bill years ago
believed archea eukarya evolved from bacteria

morphology

study of form

morphology of bacteria

are prokaryotic,

have a cell membrane and a cell wall made up of peptidoglycan (combo of protein and carbohydrate), making it different from the cell walls of Archaea and Eukaryotes

types of bacterial cell walls

gram positive and gram negative

gram positive

stains purple
thick cell wall
thick peptidoglycan wall

gram negative

stain pink
thin cell wall w/ peptidoglycan and lipoprotein
more infectious-- hard to treat
more common

how do bacterial move

use flagella or pili and interaction with environment

How bacteria reproduce

binary fission-- asexual

do bacteria go through mitosis?

NO! it is a prokaryote! no nucleus!

bacteria conjugation

exchange of DNA through conjugation tube (pilus)
-usually plasmid DNA not genomic DNA (dont wanna send the control center)

Plasmid DNA

small detached extrachromosomal DNA in cell that separates from chromosomal and can replicate independently

Stages of Bacteria growth

lag, log, stationary, death

lag phase

bacteria adjusting to new environment and growing slowly

log phase

exponential growth

stationary growth

bacteria have reached the carrying capacity of environment

death phase

logarithmic death of bacteria as nutrients get used up

classifying bacteria based on energy

photosynthesizers
chemoautotroph
heterotrophs

photosynthesis is mostly carried out by

most of photosynthesis is carried out by bacteria

cyanobacteria

type of photosynthesizers
blue-green bacteria that have chlorophyll in cell membrane
made most of earths o2 atmosphere

chemoautotroph

chemo- chemical
auto- self
troph- energy
breakdown chemical in soil ( use chem for nutrition)
waste products acts as fertilizer

heterotroph

most Eubacteria are this

alongside fungi, serve as decomposers for environment as they release nutrients back into soil after it dies

bacteria interactions

mutualism -ex: nitrogen fixing bacteria in soil
parasitism- cause disease

two ways bacteria are harmful

1) can metabolize host by using diff parts of body as food ex. TB --> disease affects lungs--> mycobacterium TB--> use lung tissue as food source

2) secreting chemical comp: toxics into environment
ex: food poisoning

treatment of bacterial disease

antibiotics-- works by punching holes in bacteria and the immune response of the body will be more effective or prevent bacteria from reproducing

how were antibiotics discovered

noticed bacteria growing in petri dish didnt grow around the fungi
concluded: fungi secrets substance that kills bacteria
penicillin

three issues with antibiotic-resistant bacteria

1) since bacteria can multiply rapidly, antibiotics may not be able to eradicate all the bacteria
then, remaining the bacteria become resistant and mutate DNA and make more
so, new cells are resistant and next infection will be hard to treat
2) since people dont finish antibiotics
then an opportunity for bacteria to reproduce and make more resistant cells
3)anti bacterial soaps
-regular use of these soaps can be more harmful because common bacteria found in skin can become resistant to these chemicals

superbug

bacterium that cant be destroyed by antibiotics

Bacteria in food production

lactobacillus-- make yummy food like pick soy sauce cheese yogurt

bioremediation

cleaning up toxic chem in environ by breaking down into less toxic products

pesticides

targets specific pests ONLY
doesnt harm anything else

bioengineering

used to reproduced specific genes -- mass-producing of protein ex insulin

other ways bacteria are classified

by respiration

aerobic

grows in presence of oxygen

anaerobic

grows in absence of oxygen

obligate aerobes

must have oxygen

obligate anaerobes

must have NO oxygen

facultative anaerobes

can live with or without oxygen