Unit 7

Question 1

what do eukaryotic cells contain?

Answer 1

organelles
- nucleus
- mitochondria
- GA
- ER
- chloroplasts

Question 2

what are eukaryotic cells bc of endosymbiosis?

Answer 2

genetic chimera

Question 3

what are the two energy producing organelles?

Answer 3

mitochondria and chloroplasts

Question 4

what are mitochondria ancestors of?

Answer 4

respiratory bacteria

Question 5

what are chloroplasts ancestors of?

Answer 5

phototrophic bacteria

Question 6

where did mitochondria and chloroplasts get their own DNA from?

Answer 6

bacteria

Question 7

what is the endosymbiosis hypothesis?

Answer 7

• established residence inside another cell type
• host cell was safe and stable
• M and C gave host cell ATP

Question 8

what is the support for the endosymbiotic hypothesis?

Answer 8

• mito and chloro have own DNA
• eukaryotic nucleus have genes from Bacteria
• organellar ribosomes and phylogeny
• antibiotic specificity
• hydrogenosomes

Question 9

mitochondria and chloroplasts contain DNA

Answer 9

• proteins are encoded by nuclear DNA
• molecules encoded by organelles genes: respiratory chain proteins (mito), photosynthetic apparatus proteins (chloro), r RNA/ t RNA
• circular, covalently closed genome (prokaryotic feature)

Question 10

eukaryotic nucleus contains genes from B

Answer 10

• ancestor of mito (chloro) had the genes
• engulfed cells showed up (intake of bacterial cells)
• genes transferred to host nucleus during transition

Question 11

organellar ribosomes and phylogeny

Answer 11

• 70S ribosomes (bacterial feature)
• cytosolic ribosomes in eukaryotic cell are 80S

Question 12

antibiotic specificity

Answer 12

• antibiotic kill or inhibit B by interrupting 70S ribosome protein synthesis functions
• same antibiotics also inhibit protein synthesis in mito anc chloro

Question 13

hydrogenosomes

Answer 13

• membrane enclosed organelles
• own DNA and ribosomes
• in certain amitochondriate eukaryotic anaerobes
• phylogenetic analyses of hydrogenosome r RNA show connected to B phylogenetically

Question 14

primary endosymbiosis

Answer 14

gave rise to chloroplast in common ancestor of green algae, red algae, plants
- mito
- chloro
- hydrogenosomes
- organelles from B

Question 15

common ancestor + chloroplasts = ?

Answer 15

green algae, red algae, plants

Question 16

secondary endosymbiosis

Answer 16

red and green algae
- cells engulfed: new cell became phototrophis
- chloroplasts stably retained
- euglenids
- chlorarachniophytes

Question 17

what is the presence of chloroplasts explained through?

Answer 17

secondary symbiotic event in green algae

Question 18

phylogenetic lineages of eukarya

Answer 18

• eukarya closer to A than B
• 18S r RNA (unreliable)

Question 19

microbial eukaryotes contain ??

Answer 19

either mitochondria or hydrogenosomes or some DNA traces of these structures

Question 20

what did mitochondrion or similar strucutre do?

Answer 20

gave new metabolic capabilities to early eukaryotic cell triggering evolutionary branching of eukaryotic microogranisms

Question 21

what was the primary endosymbiotic event triggered by?

Answer 21

O2 accumulation after cyanobacterial photosynthesis

Question 22

what are the 2 clear points in evolution of eukaryotic microbes?

Answer 22

1. composite phylogenetic tree should be created for microbial evolution based on 18S r RNA and other genes
2. primary eukaryotes acquired mitochondria- key evolutionary success of domain Eukaryotes

Question 23

what are the 7 groups of microbial eukaryotes protists?

Answer 23

• diplomonads
• parabasalids
• euglenozoans
• alveolates
• stramenopiles
• cercozoans and radiolarians
• amoebozoa

Question 24

diplomonads

Answer 24

• 2 nuclei of equal sizes
• mitosomes (reduced mito with ETC)
• no genes for many metabolic pathways

Question 25

parabasalids

Answer 25

- parabasal body (structural support to GA complex) - no mito - hydrogenosomes present - lack introns

Question 26

trichomonas vaginalis

Answer 26

- parabasalids - STD

Question 27

euglenozoans

Answer 27

- unicellular, flagellated protists - kinetoplastids - euglenids

Question 28

kinetoplastids

Answer 28

mass of DNA in single, large mitochondrion

Question 29

euglenids

Answer 29

- 2 flagella and chloroplast - feed on bacteria via phagocytosis (process of surrounding a particle with portion of flexible cytoplasmic membrane to engulf particle and bring it into cell for digestion) - chloroplasts that support phototrophic growth - in dark lose chloroplasts and live as chemoogranotrophs

Question 30

alveolates

Answer 30

cytoplasmic sacs located under cytoplasmic membrane - alveoli - alveoli help maintain osmotic balance by controlling water influx and efflux

Question 31

types of alveolates

Answer 31

ciliates - paramecium dinoflagellates - "red tides" in polluted coastal zones, blooming apicomplexans - plasmodium species-malaria, toxoplasma, structures for sporozites for transmission of parasite to new host

Question 32

types of stramenopiles

Answer 32

- have flagellum diatoms oomycetes golden and brown algae

Question 33

diatoms

Answer 33

unicellular, phototrophic, microbial eukaryotes major components of planktonic microbial community in marine and fresh water

Question 34

oomycetes

Answer 34

water molds

Question 35

golden and brown algae

Answer 35

gold- chrysophytes brown - not microbes

Question 36

cercozoans

Answer 36

foraminiferans - exclusively marine and form shell-like structures

Question 37

amoebozoa

Answer 37

- lobe-shaped pseudopodia for movement and feeding - gymnamoebas- free-living protists in aquatic and soil - entamoebas- parasites for vertebrates and invertebrates

Question 38

fungi

Answer 38

- large, diverse and widespread - yeasts, mushrooms, molds - 100,000 - phylogenetic cluster distinct from protists - microbial group most closely related to animals - in soil or dead plant matter - role in mineralization of organic carbon - plant pathogens - some diseases - establish symbiotic associations with plants - facilitate acquisition of mineral from soil - benefit humans through fermentation and making of antibiotics

Question 39

very small green algae and colonial green algae

Answer 39

volvox - flagellated cells - some motile - photosynthesis or repro