How many true breeding pea plant varieties did Mendel select as pairs, which were similar except in one character with contrasting tralts$?$

Chromosomes are made up of

When a diploid female plant is crossed with a tetraploid male, the ploidy of endosperm cells in the resulting seed is

A distinct mechanism that usually involves a short segment of $DNA$ with remarkable capacity to move from one location in a chromosome to another is called

If a diploid cell is treated with colchicine, then it becomes