Scientists think that all of life on Earth originated from which type of organism?

• A. A photosynthetic plant
• B. A complex animal
• C. A multicellular eukaryote
• D. A single-celled prokaryote

Answer: (D)

Verified step by step guidance

1. Understand the concept of the origin of life: Scientists hypothesize that life on Earth began with simple organisms capable of surviving in the harsh conditions of early Earth. These organisms were likely single-celled and lacked complex structures.
2. Learn the difference between prokaryotes and eukaryotes: Prokaryotes are simpler organisms without a nucleus or membrane-bound organelles, while eukaryotes are more complex and multicellular organisms evolved later.
3. Recognize the timeline of evolution: Early Earth conditions favored the development of single-celled prokaryotes, which were the first forms of life. Multicellular eukaryotes, plants, and animals evolved much later in Earth's history.
4. Understand why photosynthetic plants and complex animals are not the origin: Photosynthetic plants and complex animals require more advanced cellular structures and processes, which evolved after simpler prokaryotic organisms.
5. Conclude that the correct answer is a single-celled prokaryote: Based on scientific evidence, single-celled prokaryotes are considered the earliest form of life from which all other life forms evolved.