7.13 Origin of Life on Earth

• What is the prevailing scientific explanation for the origin of life on Earth?

  Abiogenesis
• Match the early Earth condition with its significance:

  Reducing Atmosphere ↔️ Allowed organic molecules to form

  Intense UV Radiation ↔️ Provided energy for reactions

  Volcanic Activity ↔️ Introduced elements from Earth's interior

  Warm Oceans ↔️ Facilitated molecular interactions
• The Miller-Urey experiment used electrical sparks to simulate lightning.


  True
• What hypothesis did the Miller-Urey experiment support?

  Abiogenesis
• What were some of the critical early Earth conditions that allowed organic monomers to form?

  Reducing atmosphere, warm oceans
• The Miller-Urey experiment in 1953 supported the abiogenesis theory by simulating early Earth's atmospheric conditions.


  True
• The Miller-Urey experiment resulted in the formation of various amino acids
• Polymerization is the process of forming macromolecules from monomers
• Why were protocells important in the origin of life?

  Provided encapsulation
• RNA can both store genetic information and catalyze chemical reactions.


  True
• Abiogenesis requires supernatural intervention to explain the origin of life.

  False
• What were the early Earth conditions that facilitated the formation of organic molecules?

  Reducing atmosphere, intense UV radiation
• Abiogenesis is the scientific theory that life arose from non-living matter
• The early Earth's atmosphere was oxygen-rich

  False
• Steps in the scientific theory of abiogenesis

  1️⃣ Life arose from non-living matter

  2️⃣ Life arose through natural processes

  3️⃣ Supernatural intervention is not involved

  4️⃣ It explains the origin of life on Earth
• The Miller-Urey experiment resulted in the formation of various amino acids.
• Match the alternative source of organic monomers with its mechanism:

  Meteorites ↔️ Direct delivery of pre-formed compounds

  Deep-sea vents ↔️ Chemosynthesis in energy-rich environments
• The abiogenesis theory proposes that life emerged from non-living matter through natural processes
• What type of atmosphere did the Miller-Urey experiment simulate?

  Reducing atmosphere
• What basic elements were available on early Earth for the formation of organic monomers?

  C, H, O, N, P, S
• A reducing atmosphere on early Earth prevented oxidation and allowed organic molecules to form.

  True
• The RNA world hypothesis proposes that early life was based on RNA rather than DNA and proteins
• What type of genetic material do mitochondria and chloroplasts have?

  Circular DNA
• The Miller-Urey experiment used methane, ammonia, water vapor, and hydrogen to simulate early Earth's atmosphere
• Early Earth's atmosphere contained an abundance of elements such as carbon, hydrogen, oxygen, nitrogen, phosphorus, and sulfur
• What was the purpose of the Miller-Urey experiment?

  Simulate early Earth conditions
• Electrical sparks in the Miller-Urey experiment simulated lightning.


  True
• What organic compounds were formed in the Miller-Urey experiment?

  Amino acids
• Match the aspect of the Miller-Urey experiment with its description:

  Atmosphere ↔️ Methane, ammonia, water vapor, hydrogen

  Energy Source ↔️ Electrical sparks

  Apparatus ↔️ Closed system with boiling water
• The reducing atmosphere on early Earth allowed organic molecules to form without oxidation
• What role did volcanic activity play in the formation of organic monomers on early Earth?

  Introduced elements and energy
• What organic molecules were delivered to early Earth by meteorites?

  Purines and pyrimidines
• Polymerization is the process of forming macromolecules from monomers
• Basic elements such as carbon, hydrogen, oxygen, nitrogen, phosphorus, and sulfur were essential for polymerization.


  True
• The RNA world hypothesis proposes that early life on Earth was based on RNA
• The RNA world hypothesis suggests that RNA-based organisms predated DNA-protein systems
• RNA has catalytic activity, while DNA does not
• Match the function with the molecule:

  Genetic Storage ↔️ RNA, DNA

  Catalytic Activity ↔️ RNA, Proteins
• The endosymbiotic theory posits that eukaryotic cells evolved by incorporating prokaryotic organisms
• What type of ribosomes do mitochondria and chloroplasts have?

  Prokaryotic-like