Question: how many chromosomes are in a rat's body cells?
Answer: The chromosome numbers of the albino rats (Rattus norvegicus) have been reported to be 42 in diploid and 21 in haploid by many authors in the study of germ cells (cf. Makino's list, 1951). In the present study the somatic chromosomes were observed in the tissue cells of various organs in the foetal rat.