Final answer:
Nonvascular seedless plants, such as mosses, hornworts, and liverworts, do not have a vascular system.
Step-by-step explanation:
A plant that does not have a vascular system is known as a nonvascular seedless plant or a bryophyte. Nonvascular seedless plants lack vascular tissue, which is specialized tissue that transports water, nutrients, and food in plants. Examples of nonvascular seedless plants include mosses, hornworts, and liverworts.