Quiz on Luca: The Progenitor of Life

What does Luca stand for?

• Last Universal Common Ancestor

• Last Unique Common Ancestor

• Last Unique Common Animal

• Last Universal Common Animal

How long ago did Luca exist?

• 3.5 billion years

• 5.0 billion years

• 4.2 billion years

• 2.5 billion years

What type of organism was Luca?

• Multi-celled organism

• Plant-like organism

• Fungi-like organism

• Single-celled bacterium-like organism

What geological aeon is referred to as Hadean?

• The time before 4 billion years ago

• The time after 4 billion years ago

• The time of the dinosaurs

• The time of the ice ages

What does the study of molecular phylogenetics help scientists deduce?

• The physical appearance of ancient organisms

• The order of species splitting off in evolution

• The climate of ancient Earth

• The exact age of fossils

What was the atmosphere of early Earth primarily composed of?

• Oxygen and nitrogen

• Carbon dioxide and methane

• Hydrogen and helium

• Argon and neon

What type of metabolism might Luca have had?

• Aerobic

• Chemoautotroph or heterotroph

• Photosynthetic

• Anaerobic

What kind of immune system did Luca possess?

• Innate immune system

• Antibody-based system

• Cell-mediated immunity

• CRISPR-Cas-like apparatus

What does horizontal gene transfer allow?

• Creation of new species

• Sharing genes between unrelated organisms

• Elimination of harmful genes

• Mutation of existing genes

What is one implication of Luca's existence?

• Life only exists on Earth

• Life is likely to be abundant in the universe

• Life is only found in extreme environments

• Life is extremely rare in the universe