Origin of Life Quiz

The theory of chemical evolution suggests that life originated from:

• A primordial soup of organic molecules formed by natural processes

• Pre-existing life on another planet brought to Earth via comets

• Spontaneous generation of complex life forms from non-living matter

• A sudden appearance of DNA-based life forms

Which of the following molecules is considered the first genetic material?

• DNA

• RNA

• Proteins

• Lipids

Which of the following best explains the significance of the Miller-Urey experiment in 1953?

• It demonstrated how life forms can evolve over time.

• It showed that simple organic molecules can form from inorganic compounds under early Earth conditions.

• It discovered that DNA was the basis of heredity in living organisms.

• It proved that life originated from outer space.

Which atmospheric condition was least likely present on early Earth before life began?

• High levels of oxygen

• Volcanic activity

• Frequent lightning storms

• Presence of water vapor and methane

Which hypothesis about the origin of life suggests that organic compounds were delivered to Earth via comets or meteorites?

• Abiogenesis

• Chemical evolution

• Panspermia

• Spontaneous generation

Which structure is considered an example of a protobiont, an early precursor to living cells?

• Nucleotides

• Coacervates

• Ribozymes

• Lipids

In the context of the origin of life, what is the significance of hydrothermal vents?

• They are considered the site where photosynthetic life first evolved.

• They provided the ideal environment for the synthesis of complex organic molecules.

• They contributed to the increase of oxygen in Earth’s early atmosphere.

• They led to the first formation of eukaryotic cells.

Which of the following is not a characteristic of the last universal common ancestor (LUCA)?

• Use of DNA as genetic material

• Presence of a cell membrane

• The ability to perform photosynthesis

• Ribosomes for protein synthesis

The 'RNA world' hypothesis suggests that:

• Proteins were the first macromolecules to appear on Earth

• RNA molecules could have acted as both information carriers and catalysts in early life forms

• DNA was the first genetic material but was later replaced by RNA

• The first forms of life used RNA solely as structural material

Which of the following conditions was crucial for the formation of organic molecules in the early Earth's atmosphere, according to the Oparin-Haldane hypothesis?

• Presence of ozone layer

• A reducing atmosphere with little or no free oxygen

• High concentrations of free oxygen

• Abundant chlorophyll molecules