Origin of Eukaryotes

Flashcards about the Origin of Eukaryotes

What is the central issue in the evolution of eukaryotes?

How did cooperation evolve?

What is favored in competition with cooperative organelles?

Energetically selfish organelles

What role of mitochondria offers vestiges of early conflict?

Programmed cell death (PCD)

Approximately when is plastid acquisition dated to?

About 2,000 Ma

How many genomes can a cell have after secondary acquisitions?

5 genomes

What innovation fulfilled the promise inherent in moving small cells inside a bigger cell?

ADP/ATP carriers (ADP/ATP translocase)

What do ADP/ATP carriers (AACs) promote?

Metabolic homeostasis

What evolved as a byproduct of ADP/ATP carriers?

An ATP-rich cytosol (and eukaryotic complexity)

What happens if conflict mediation fails?

Defecting proto-organelles would be selected for, and the symbiosis would collapse.

What two characteristics of life are divided in eukaryotic cells?

Energy conversion and information/reproduction

Which two symbionts have been fully integrated into the cell?

Mitochondria and chloroplasts

What processes are governed by mitochondria and chloroplasts?

Respiration and photosynthesis

What is central to the cooperation that produced the eukaryotic cell?

Chemiosmosis

What likely post-dated mitochondria, but not be much?

Plastids

What is the likely number of primary acquisitions of cyanobacteria by eukaryotes?

One

What does the gene family of ADP/ATP carriers (AACs) include?

Uncouplers and phosphate carriers

What does PCD stand for?

Programmed Cell Death

What role do mitochondria play in PCD?

Release of cytochrome c and other factors

What is the function of uncouplers?

Break down the proton gradient

What is the function of phosphate carriers?

Complement AACs

What interaction was aerobic metabolism related to?

Origin of Eukaryotes

Why haven't several lineages of prokaryotes become eukaryotes?

Eukaryotes are monophyletic

What issues were central to achieving a stable symbiosis?

Conflict mediation

What mediates conflict and provides metabolic homeostasis?

ADP/ATP carriers and uncouplers

What vestiges of the conflictual stages of the symbiosis remain?

Mitochondria’s role in programmed cell death

What metabolic process is associated with mitochondria?

Respiration

What metabolic process is associated with chloroplasts?

Photosynthesis

What factors dominate the carbon cycle?

Respiration and photosynthesis

What were the likely features of proto-eukaryotes?

Division of labor between energy conversion and information/reproduction

Where are centrosomes or microtuble-organizing centers from?

Spirochete bacteria