If a certain mammal has a haploid number of 13, how many chromosomes are there in a. a somatic cell? b. a germ cell (

The answers are 26 and 13 respectively.

Haploid cells means that the cells has a half number of chromosomes in the nucleus than other normal cells. These cells are results of meiosis, which is a kind of cell division that produces 4 genetically different daughter cells. The cell divides without duplicating its genetic material. Common haploid cells include such as gametes.

In opposite of haploid cells, we have diploid cells. They have 2 sets of chromosomes, which is the full set that the organisms could have. They're usually the results of mitosis, a kind of cell division that produces 2 daughter cells that are genetically identical to both the other daughter cell and the parent cell. They are important for activities such as growth, repair etc. These diploid cells appears in somatic cell, aka the normal body cells.

Therefore, there you have it, somatic cells has 2 sets of chromosomes, so it's 13 + 13 which makes it 26, and gametes, in haploid condition, a given 13.