Answer: You picked the correct answer, "They all inherited their traits from a common ancestor."
Explanation: Well, one I had a test on this question too and I got it right. Second, if all species shown have something in common (structures) than they most likely got it from a common ancestor.
The term ‘Crossing over’ was used by Morgan and Cattell. It is a process in which there is exchange of chromosome segments between non-sister chromatids of a homologous chromosomes. It occurs during pachytene stage of prophase I of meiosis cell division.
Significance of crossing over:
- Crossing over provides genetic variation in all sexually reproducing organisms.
- It creates new combination of genes or genetic recombination and produces hybrids.
Hi!
Could you please be more specific, so that I can answer your question properly? Layer of what?