Test 3 (Eukaryotes) Flashcards
Mitochondria and chloroplasts
-once free living bacteria (own circular DNA, own ribosomes (bacterial, smaller)
-divide by binary fission
Endosymbiosis
-Endo (one is inside the other) symbiosis (organisms liver very close to each other)
- Multiple cells living together to produce one eukaryotic cell
-Achaea cell engulfed an aerobic bacterium which became mitochondria leading to animals and fungi (ancestor to all eukaryotes
- second engulfment of cyanobacteria which became chloroplasts.
Don’t forget to name organelles and their function
Cell wall characteristic of Eukaryotics (all have cell membrane
Animals
Plants
Fungi
Protists
No cell wall
cellulose
chitin
varies, protozoan (none), algae made of cellulose
Fungi
-Chemoheterotrophs by absorption (digestion occurs outside then absorb)
-multicellular or secondary unicellular
-YEAST,,,,secondary unicellular (ancestors had multicellular
-MOLDS,,,hyphae + reproductive structure (multi),
-some fungi switch between forms
-more acid/salt/sugar tolerant than bacteria
Septate fungi vs non-septate fungi
septate cell walls that separate fungi cells
non-septate, no dividers.
Mycellium
Hyphae collectively together
Fungi reproduction (Asexual)
-Asexual or Sexually
-hyphae are haploid, but they produce a reproductive structure which makes spores by mitosis.
- spores germinated, divide by mitosis to produce a new mycelium.
Fungi reproduction (Sexual)
- hyphae strands from different mating strains fuse (- and +)
- which produce a dikaryotic (2 nuclei) not fuse together yet)
-at some point the nuclei fuse to form a diploid reproductive structure.
-then spores made by meiosis (different cells)
why we care about fungi?
decompose cellulose, chitin, petroleum (bioremediation) . ammonification
Mycorrhiza ?
-fungal relationship between plants
- sugar from plants to fungi
-water and minerals from fungi to plants (due to large surface area)
Mycoses (fungal disease )
-superficial like (ringworm, athletes foot)
-opportunistic pathogen (antibiotic use kills yeast) thrush, yeast infections
-histoplasmosis - respiratory fungal disease
-plant diseases
-animal mycosis
-white pine blister rust
-white nose syndrome
Protists
-Not monophyletic (not close relatives)
-Diverse groups
-Algae (unicellular, colonial (many cells stuck together), often motile
-photoautotrophs
-Examples: spirogyra, diatoms
Protists significant to human
-aquatic food chains (algae + cyanobacteria photosynthesis)
-oxygen generation (more O2 than plants)
-red tides (blooms dinoflagellates, make toxin that accumulate in shellfish)
-secondary endosymbiosis. (green algae + plants) another engulfment led to red and brown algae.
Protozoa
-Chemoheterotroph, motile, no cell wall, free-living or parasitic.
-Sexual or asexual.
Trophozoite and cyst (Protozoa)
- Trophozoite stage (actively growing form)
- cyst (inactive form) surviving form,harder to kill when environment better turn back to Trophozoite.
Protozoa examples and diseases
-Amoeba/paramecium
-Malaria
-African sleeping sickness
-changas disease.
Slime molds/Water molds (protists)
-part of their life as Amoebas
-cAMP signals them to come together into a SLUG (it is motile)
-when reach destination, develops into a reproductive structure that produces spores.
-spores become amoebas, repeating the cycle.
-decomposers of cellulose.
Irish potato famine (caused hunger) caused by Late blight (potato disease)
Helminths
-Parasitic worms
-Animalia
-Nematodes (roundworms), Trematodes (flukes), Cestodes (tapeworms)
-Chemoheterotrophic, maybe be by absorption, may lack digestive tract
Definitive host vs intermidiate host
-host where parasite reproduces sexually
-host where parasite grows but reproduce asexually.
(Tapeworms) cestodes
scolex, proglottids
scolex, holds on to intestinal wall
proglottids, have ovaries + testes which shed eggs/larvae in feces.
encysted larvae can end up in the brain or muscle if humans ingest the eggs or larvae ending in intermediate host.
Pinworms (nematode)
-eggs ingested
-mature in intestine (male + female mate)
-female travels to anus to lay eggs, leads to itching
-reinfection due to fingers in mouth
(pathogens change host behavior or physiology to increase spread (itching)