Here's why:

* Chromosomes are the carriers of genetic information. This information is essential for both plants and animals to function, grow, and reproduce.

* All living organisms, including plants and animals, have DNA. DNA is organized into chromosomes.

* The number of chromosomes varies between species. For example, humans have 46 chromosomes, while a fruit fly has 8.

Important note: While both plant and animal cells have chromosomes, there are some differences in their structure and organization. For example, plant cells often have larger, more numerous chromosomes than animal cells.