Objectives
1. Differentiate between spontaneous generation and biogenesis.
2. Sequence events that might have lead to cellular life
3. Describe the endosymbiont theory
Use the links below to access lessons on hypotheses for the origins of life (top left), on cellular evolution (top right), the endosymbiont theory (bottom left) and assessments for this section (bottom right).
PA State Standards
3.1.B.A1: Describe common characteristics of life. Compare and contrast the cellular structures and degrees of complexity of prokaryotic and eukaryotic organisms. Explain some structures in eukaryota cells developed from early prokaryotic cells (Mitochondria and chloroplasts).
3.1.B.C2: Describe the theory suggesting that life on Earth arose as a single, primitive prokaryote about 4 billion years ago, and that for the next 2 billion years, a huge diversity of single-celled organisms evolved. Analyze how increasingly complex, multicellular organisms evolved once cells with nuclei developed. Describe the relationship between environmental changes and changes in the gene pool of a population.
3.1.10.C1 Explain the mechanisms of biological evolution
ISTE Standards
Empowered Learner - students leverage technology to take an active role in choosing, achieving, and demonstrating competency in their learning goals, informed by the learning sciences.
Digital Citizen - students recognize rights, responsibilities, and opportunities of living, learning, and working in an interconnected digital world, and they act and model in ways that are safe, legal, and ethical.
PA State Standards
3.1.B.A1: Describe common characteristics of life. Compare and contrast the cellular structures and degrees of complexity of prokaryotic and eukaryotic organisms. Explain some structures in eukaryota cells developed from early prokaryotic cells (Mitochondria and chloroplasts).
3.1.B.C2: Describe the theory suggesting that life on Earth arose as a single, primitive prokaryote about 4 billion years ago, and that for the next 2 billion years, a huge diversity of single-celled organisms evolved. Analyze how increasingly complex, multicellular organisms evolved once cells with nuclei developed. Describe the relationship between environmental changes and changes in the gene pool of a population.
3.1.10.C1 Explain the mechanisms of biological evolution
ISTE Standards
Empowered Learner - students leverage technology to take an active role in choosing, achieving, and demonstrating competency in their learning goals, informed by the learning sciences.
Digital Citizen - students recognize rights, responsibilities, and opportunities of living, learning, and working in an interconnected digital world, and they act and model in ways that are safe, legal, and ethical.
Main Ideas
Spontaneous generation was disproved in favor of the theory of biogenesis. Organic molecules, like amino acids, might have been formed from simpler, inorganic molecules, present on early Earth. The first cells which formed were likely autotrophic and prokaryotic, likely similar to modern Archaea. The endosymbiont theory explains how Eukaryotic cells might have evolved from prokaryotic cells.
Spontaneous generation was disproved in favor of the theory of biogenesis. Organic molecules, like amino acids, might have been formed from simpler, inorganic molecules, present on early Earth. The first cells which formed were likely autotrophic and prokaryotic, likely similar to modern Archaea. The endosymbiont theory explains how Eukaryotic cells might have evolved from prokaryotic cells.