Eukaryotic Taxonomy

how was the eukarya phylogeny constructed

how was the eukarya phylogeny constructed

sequencing 18S rRNA

multi low sequence typing

red algae

marine

multicellular mostly

also called rhodophytes

example of unicellular red algae

galderia - acidic hot springs

why is red algae red

phycoerythrin which is an accessory pigment

it is produced more at greater depths to help photosynthesis

green algae

aka chlorophytes

closely related to plants

freshwater

endolithic algae grows inside porous rocks

what kind of reproduction does green algae have

sexual and asexual

what do amitochondriate eukaryotes have instead of mitochondria

mitosomes or hydrogenosome

what is a mitosome

reduced mitochondria

cannot do TCA or respiratory chain

involved in maturation of iron-sulfur clusters

what is a hydrogenosome

present when metabolism is strictly fermentative

arose from secondary endosymbiosis

what are cysts

similar to endospores

protect cells against poor conditions

survival of starvation, desiccation, or infection

characteristics of diplomonads and parabasalids

unicellular, flagellated

no chloroplast

anoxic habitats

diplomonads

two equal nuclei

mitosomes

parabasalids

parabasal body (support in golgi complex)

hydrogenosomes

live in intestinal tracts

example of a diplomonad

giardia lamblia

intestinal infection

example of parabasalid

trichomonas vaginalis

STD in humans

does not form cysts

cannot survive outside of host (hence need for sexual transmission)

euglenozoans

unicellular, flagellated

kinetoplastids

have a kinetoplast

live in aquatic habitats

can be disease causing

what is a kinetoplast

a mass of DNA present in the single large mitochondrion of a kinetoplastid

example of kinetoplastid

trypanosoma brucei

african sleeping sickness

grows in blood stream and causes CNS infection

the single membrane is enclosed in a membrane flap

euglenids

nonpathenogenic, phototrophic

contain chloroplasts, but can lose it if living in the dark and will switch to become a heterotroph

feed on bacteria by phagocytosis

alveolates

have alveoli

contains ciliates, dinoflagellates, apicomplexans

what are alveoli

sacs under the cytoplasmic membrane that maintain osmotic balance within the cell by filling or emptying

ciliates

have cilia for motility and food getting

macro and micronuclei

sometimes are parasites but they also live in rumen to help digestion

what is an example of a ciliate

paramecium

during conjugation (sexual reproduction) the two paramecia exchange micronuclei

dinoflagellates

phototrophic

can be free living or symbiotic

two flagella with different insertion points

what are the two types of flagella in dinoflagellates

transverse flagellum: used for locomotion

longitudinal flagellum

how are dinoflagellates toxic

some species secrete neurotoxins

in the right conditions, populations will bloom and form red tides

poison for humans can bioaccumulate in shellfish

apicomplexans

obligate parasites

complex life cycle

contain apicoplasts

what are apicoplasts

degenerate chloroplasts that lack pigments and phototrophic capacity but still have some anabolic pathways

what are examples of apicomplexan diseases

malara (plasmodium)

toxoplasmosis (taxoplasma)

coccidiosis (eimeria)

stramenopiles

flagella with many short hairlike extensions (branching)

chemoheterotrophs and phototrophic

examples: oomycetes, golden algae, diatoms, brown algae

oomycetes

chemoheterotrophs

hyphae forming (one big cell)

cell wall is made of cellulose

example of oomycetes

phytophthora infestans - irish potato famine

golden algae

phototroph

golden brown colour is caused by fucoxanthin in the chloroplast

diatoms

unicellular, phototrophic

have frustules

what are frustules

cell walls made of silica with proteins and polysaccharides attached to it

protects the diatom against predation

what are pseudopodia

cytoplasmic projections

cercozoans

pseudopodia

marine

form tests (shell-like structures made from organic material)

radiolarians

pseudopodia

marine, heterotrophic

tests are made of silica

radial symmetry

amoebozoa

use pseudopodia for movement and feeding

(cytoplasmic streaming and phagocytosis)

gymnamoebas, entamoebas, slime molds

gymnamoebas

free living in soil and aquatic environments

entamoebas

parasites of vertebrates of invertebrates

entamoeba histolytica

slime mold

production of fruiting body with spores for dispersal

can move rapidly across surfaces

plasmodial slime mold life cycle

form a sporangium that makes haploid spores (dormant)

study slide

fungi

form hyphae

hyphae produce asexual spores (conidia)

what are the two types of hyphae

septate - separated by cell walls

coenocytic - one large cell with many nuclei

symbiosis of fungi

form mycorrhizae with plant roots

help plants obtain phosphorous and the fungus obtain nutrients from the plant

ectomycorrhizae

form a sheath around the plant root but does not penetrate it

endomycorrhizae

the hyphae is embedded in the plant root

bad symbiosis with fungi

can cause disease

specialized hyphae (haustoria) that enter plant cells and consume the cytoplasm

ex. mycoses - athlete’s foot

types of asexual reproduction in fungi

growht and spread of hyphal filaments

asexual reproduction of spores

simple cell division (budding yeast)

sexual reproduction in fungi

spores

fusion of two haploid cells and then meiosis to make haploid spores

spores are resistant

saccharomyces cerevisiae reprodution

cell division occurs through budding

chart on slides - know for exam