3: Origin of Eukaryotes

Question 1

Prokaryotic cell

Answer 1

Small (1-10mm)
Nucleoid (loose in cyto
No chloroplast
No mitochondria
Call wall (peptidoglycan)
Simple flagella
No tissue
Haploid
Sexual repro absent

Question 2

Eukaryotic Cell

Answer 2

Large (10-100mm))
Membrane bound (nucleus, chloroplast, mitochondria)
No peptidogylcan
9+2 flagella
Tissue
Haploid & Diploid
Sexual repro

Question 3

Endosymbiosis Theory (how eukaryotes evolve
Steps (4)

Answer 3

1) Endomembrane system
2) Mitochondria
3) Flagella
4) Chloroplast

Question 4

Endomembrane System
1) How
Where is genetic material attached in 
2) Prokaryotes
3) Eukaryotes

Answer 4

1) Evolved through the invagination of cell membrane
2) Cell membrane
3) Endoplasmic membrane

Question 5

Mitochondria
1) Evolved though
Where does oxidative phosphorylation occur in
2) Prokaryotes
3) Eukaryotes

Answer 5

1) Invasion of an anaerobic prokaryote by a small aerobic bacterium
2) Across the plasma membrane (no mito)
3) In mito

Question 6

Mitochondria

Similar to bacteria

Answer 6

1) Own genetic material
2) New created through process similar to binary fission (bigger & bigger then pinch in middle)
3) Smaller ribosomes
4) Drug sensitivity similar
5) Paracoccus denitrificans - similar composition & antibiotic sensitivity

Question 7

Flagella

1) Evolved by

Answer 7

1) Independently from eukaryote cytoskeleton, not through incorporation of a prokaryote with flagella

Question 8

Cytoskeleton
1) Composed of
What is composed of
2) Actin
3) Tubulin
4) 13 Filaments

Answer 8

1) Microfilaments, intermediate filaments & microtubules
2) Microfilaments
3) Microtubules
4) Microtubules

Question 9

Chloroplast
Why are they similar to bacteria
1) Ribosomes
2) Nucleotides

Answer 9

1) a. Smaller than eu
b. Inhibited by chloramphenicol
2) a. in circular form
b. not bound by membrane
c. no histone proteins

Question 10

Chloroplast
Evolve:
1) Chloroplast
2) Plastids
3) Complex plastids

Answer 10

1) Evolved once (monophyletic) through incorporation of a primitive cyanobacterium
2) Resulted in retention or loss of pigments
3) Via secondary or tertiary endosymbiosis

Question 11

How to find out how many endosymbiotic events we have had?

Answer 11

Look at the organelle with the highest amount of membranes, as each time an endosymbiosis event occurs the organelle would gain two membrane

Question 12

Secondary Endosymbiosis

1) Define
2) What happens

Answer 12

1) A non-photosynthetic eukaryote engulfs a eukaryote with a primary plastid
2) a. 4 plastid membranes present
b. plastic nucleus reduced to a nucleomorph
c. Gene transfer from nucleomorph to host nucleus

Question 13

How many membranes in each endosymbiosis:

1) Primary
2) Secondary
3) Tertiary

Answer 13

1) 2
2) 4
3) 6