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photoreceptors --> respond to change in light intensity
photoreceptors & photosynthetic pigments
control the localized distributions of organism in habitats
move toward or away from light
towards favourab;e chemical environment
eucaryotics microbes
sexual attractants for sexual reproductions
if occur, morecomlicated e.g slime molds
for 'social lives" eg cellular lime molds --> scarcity of food --> release chemical --> attract to frm assemblages of many cells
rare among fungi, protozoa and algae
bacterial chemotaxis
presence of chemoreceptores
chemoreceptors: proteins on cell wall /membrane
function:
to sence its concentrations
bacteria --> sence concentration through gardient of repellent/ attractants
summary: favourable concentration of gradient --> tumbling is supressed and vice versa
movement in decreased concentarion of repellant
pathlength of runs increases, frequency of tumbles decreases
movement in increased concentartion of repellant
pathlength of runs decreased, frequency of tumbles increases
movements in decreased concentration of attractants
pathlebgth of runs decreased, frequency of tumbles increased
movements inincreased concentrations of attractants
pathlenght of length increased, frequency of tumbles decreases
movement in isotrophic solution of attractant
swims for short periodin straight lines, tumbles & resumes swimming in different straightlines. similar pathlength
to sence presence /absence of attravtants/repellents
-ve: chemoreceptors: repellants
+ve chemoreceptors : attractants
method
sporulation
eg: fungi --. smaller than parent cell, many spores at one cycle
budding
eg: yeast --> smaller buds compare to maximum buds = 20
separation of daughter cells --> autolytic enzymes
new cells --> uniform in size
smaller in size , shorter generation time
eucaryotic cells ( algae, protozoa, fungi, zoospores)
major by using falgellum, cilia,amoeboid movements
major by using flagellum
rigidation
less osmotic damage
penetration of host tissue and other substrates
prevent phagocytosis 7 amoeboid movements
synthesis & lysis at septal region of dividing cells --> determine formations of chains /clumps
components of cell walls --> determine surface properties of ce;ll walls
peptidoglycan --> site of action of penicillin
determine
resistants to osmotic stress
shapes
eg cell walls
eucaryotic cells (ptotozoa)
ingoing activity
organism wiyhout rigid cell wall --> invagination of cell membrane
outgoing axtivuty
outer cell membrane fused with membrane systems within the cell
procaryotic cells
site of energy-yielding terminal respiratory system
semi-permeable
importance
site of nutrient, ion, & protontranslocating systems
maintaining levels of nutrients metabolites. slats, pH in the internal evironment
permeability properties
eucaryotic cells
recombinant process: mainlty sexual reproduction
mitosis and meiosis --> daughter cells have correct coplement of genetic info
transcription --> migration of mRNA into cytoplams --> translation
enclosed by membrane
DNA bound to basic proteins
procaryotic cells
recombinant process: conjugation, transduction
part of the genome is transfered
transcription & tarnslations, protein synthesis can occur simultaneously
single closed loops of dsDNA
lying free in the cells
startegy larger organism to counteract tendency to fall
eg: flagellated algae -swimming upwards
clumps --> settle more raidly
smaller organism - suspension
larger organism, settle > rapidly
reduce activity related to cell membrane
reduce ratio of surface to volume ratio
motile organism --> greater speed attained
gerater storage of food materials
greater adaptability
biological walfare
mostly disease causing in human, animals & plants
eq HIV, smallpox, herpes simplex
utilize host machinery & metabolism to reproduce
steps
release = assembled viruses are releaed
asembly = newly synthesized viral components are assembled
replication = virus induces host cell to synthesize components for its replications
penetration = nucleic acid of the virus moves into cytoplasm of host cells
attachment/ absorption = virus attached ti receptors on host cell walls
inability to carry out cell division as procaryotes and eucaryotes
inability to reproduce independent of cells
presence of either DNA or RNA
cannot replicate outside the cells
obligate intracellular parasites
environmntal applications
bioremediations
remove dentrimental pollutants from the environment
symbiotics relationship
Interactions: commensalism, parasitism, mutualism eg: N fixing bacteria provide source of N for plants
recycling of chemical compounts
convert organic materiaks to CO2
convert inorganic materials to organic materials
autotrophs
chemotrophs
photoautotrophs
higher mutation rate
quick evolution
shorter generation time
cellular organizations
genome 1/1000 smaller than eucaryotic genome
no other membrane compartments
DNA not enclosed in membrane
various morphology
ecoological role
interaction with higher microorganism
mutualistic relationship eq : with ruminants
acts as barrier to passage of pathogens ( digestive tract of ruminant)
degardation of fibrous plants materials
parasitic relationship ( harm to host )
sporozoans: Plasmodium causes malaria
in marine food chain
eg: zooplankton ingest phytoplankton and bacteria
some terrestrial (soil)
moist habitat ( fershwater /marine)
sexual: conjugation
asexual : binary fission
cytoplasm --> cytokinesis
nucleus --> mitosis
saprozoic
soluble nutrient --> pinocytosis --> diffusion, carrier mediated resonses
holozoic
solid nutrients --> phagocytosis --> cytostome
motile eucaryotics unicellular protist
ecology
seaweed eg: Rhodophyta & phaeophyta algae
oogenia (eggs) + antheridia (sperms) --> zygote
asexual
binary fission
nuclear division --> division of cytoplasm
spores
non-motile spores = aplanospores
flagellated motile spores = zoospores
nor,mals vegetative cells or sporangia
ex
thallus breakup --> fragmentation parts --> new thallus
Subtopic
nutrition
heterotrophs
chemoheterotrophs
autotrophics
classification
reproductive structures
chlorophyll & pigments
flagella number & location
cell wall
distribution
terrestrial
endosymbionts in protozoa, worms, corals, fungi (lichens)
moist, rocks, trees, soils
primarily aquatics
Neustonic
at water atmosphere interface
benthic
attach & living on bottom of water
Planktonic
phytoplankton
suspended in aqueous environment
photoautotrophics
diffrences with other photosynthetic eukaryotes
lack true leaves, roots, flowers & etc
simple reproductive structure
lack vascular conducting system
simple "aquatic plants"
ecological function
cause disease in plantseg. tobacco plants, potatoes, grapes
recycling of nutrients
decomposer & consumerin ecosystem
engulf bacteria (predator)
habitat
terrestrial habitat eg. soil, decaying wood, dung and etc
divisions
Myxomycota
glistening, viscous masses of slime
phagocytosized dead materials
multinucleated
plasmodials (acellular)
oomycota
decomposers in aquatic system
sexual reproduction
true fungi in appearance => finely branced filaments (hyphae
Acrasiomycota
plentiful of food --> divide by food & cytokinesis
feed phagosytically
individual amoeboid cells
celular slime molds
characteristic
differents in cellular organization,reproduction and life cycle
resemble fungi (lifestyle & appearance)
ecological impacts
pathogens
harmful to organism
produces natural carcinogen and aflatoxin
causes athletes foot, ringworm, &yeast infection
improve plants growth
eg: micorrhizae
spoilers
decompose food , wood, etc
modify habitat
lichens - inhabit hospitable places --> make habitat suitable
decomposers
recycling carbon, nitrogen, & other elements to ecosystem
reduce complex polysaccharides & proteins
morphological and ecological grouping
lichen
ecological role
sensitive environmental indicators
photobiont
synthesize organic nutrient from CO2
mycobiont
absorb nutrients
protection from sunlight and dessication
primary succession
making abiotic world habitable to biotic world
involve ascomycete fungi (mostly) and basidiomycete
association of fungus & photosynthetic symbiont --> thallus
mycorrhizae
benefits
fungi
feeding from tissues of the plants
plants
increase growth potential
increase surface area
mutualistic ( plant root & fungi)
reproduction
asexual
genetic diversitification (less urgent)
maximise production
condition stable
sexual
spore production (mitosis and cell division)
production new buds (yeast)
division of parent cell
generate diversity diversification
condition change (unfavourable)
Feeding forms
Mutualistic heterotrophs
feeding of /living of without damaging the host --> host & fungi benefit
Parasitic heterotrophs
feeding on living hosts
Saprobic heetrotrophs
feed on dead or decaying organic matter
types
club (Basidiomycetes)
sac (Ascomycetes)
zygote (Zygomycota)
chytrids (Chytridiomycota)
breakdown lignin deposits into smaller species
decompose cellulose
obligate anaerobe
Neocallismastigales
characteristics
no chlorophyll
rigid cell wall (chitin)
saprophytes
absorptive heterotrophs
spore-bearing organisms
multicellular and multinucleated (except yeast)