noun
monoploid number; basic chromosome number
Technical term in genetics and cytology referring to the number of chromosomes in a single set (x). Used in contexts such as polyploidy and genome analysis.
コムギの基本数は7である。
The basic chromosome number of wheat is 7.
倍数体では基本数が倍数化している。
In polyploids, the basic number is multiplied.
半数体 (haploid) has one set of chromosomes, so its chromosome number equals the basic number.
Compound of 基本 (basic) and 数 (number). The term is a direct calque from English 'basic number' used in genetics.