1st life on earth was
- cyanobacteria
- chemohetrotrophs
- autotrophs
- photoautotrophs.
The Correct Option is B
Solution and Explanation
First life form on earth was chemoheterotrophs. These organisms obtain their energy by fermenting the complex organic substances that are available in the sea. They are mainly anaerobic. They have a major role in nutrient cycling and energy transfer. They live in a diversity of areas like soil and water and even gastrointestinal tracts of animals.
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- Which one of the following options gives one correct example each of convergent evolution and divergent evolution?
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Concepts Used:
Evolution
Evolution is a process that occurs in changes in the genetic content of a population over time. Evolutionary change is generally classified into two: microevolution and macroevolution. The process of changes in allele frequencies in a population over time is a microevolutionary process. Three main mechanisms that cause allele frequency change are natural selection, genetic drift, and gene flow. On the other hand, macroevolution refers to change at or above the level of the species.