Question

explain Mendel experiment on Inheritance of traits considering only one contrasting characteristic what was his conclusion

Answer 1

Mendel performed experiment on pisum sativum( garden pea ) and worked out the main rules of inheritance.
After selecting garden pea as a experimental material, Mendle performed experiment to study the inheritance of some of the pair of contrasting character like tall and short , white and violet flowers, round and wrinkled seed, axial and terminal flowers and so on.

when Mendle crossed a tall plant (with TT trait DNA ) with a dwarf plant ( of tt trait on DNA ), the F1 generation was found to be tall.
There were no dwarf or medium height plants in F1 generation.

This means that only one parental character was seen. But when F1 generation plants were self-fertilized, it was found tallness and dwarfness characters were inherited in F1 generation from the parents, but only the character for tallness was expressed.

Thus two copies of each character are inherited in each sexually reproducing organism which may either identical or different.

CONCLUSION: The experiment indicated that plants having either TT or Tt traits were tall while with tt trait were dwarfness.
In other words a single trait "T" is enough for making plant tall but for dwarfness traits "tt" are required. Thus "T" is called dominant trait and "t" is called as recessive trait.