What Was the Ancestor of Everything?

What is the main limitation of using fossils to understand the origins of life?

• Fossils are too fragile to study.

• Fossils only provide information about extinct species.

• Fossils do not go back far enough in time.

• Fossils are difficult to find.

What was Carl Woese's significant contribution to the study of life's origins?

• He discovered the first fossil.

• He proposed the theory of evolution.

• He invented genetic sequencing.

• He discovered a new domain of life called archaea.

What are progenotes according to Woese's model?

• Complex multicellular organisms.

• Simple genetic materials surrounded by a membrane.

• Fully developed cells with DNA.

• Fossils of ancient bacteria.

In the RNA world hypothesis, what role does RNA play?

• RNA is a structural component of cells.

• RNA is responsible for photosynthesis.

• RNA acts as a catalyst and stores genetic information.

• RNA only stores genetic information.

What is the goal of the minimal genome approach?

• To identify the smallest set of genes necessary for life.

• To find the largest genome possible.

• To sequence the human genome.

• To compare genomes of different species.

How has the genetic revolution impacted the study of LUCA?

• It has proven that LUCA never existed.

• It has shown that all life is unrelated.

• It has made fossils irrelevant.

• It has allowed for the sequencing of thousands of genomes.

What environment is suggested as LUCA's habitat based on recent research?

• Hydrothermal vents

• Forests

• Oceans

• Deserts

Why might LUCA's descendants have lost certain genes over time?

• Environmental changes made some genes unnecessary.

• Genes are never lost; they only evolve.

• LUCA's descendants were less complex.

• Genes were destroyed by meteor impacts.

What is one reason why the true nature of LUCA is still debated?

• LUCA is a myth created by scientists.

• There is no evidence of LUCA's existence.

• Different models and research provide varying pictures of LUCA.

• All scientists agree on LUCA's characteristics.

What is the significance of finding genes in both archaea and bacteria?

• It suggests they traded genes recently.

• It proves they are the same species.

• It shows they evolved independently.

• It indicates a common ancestor like LUCA.