Final answer:
Moss, particularly Sphagnum or peat moss, is a seedless plant used as a renewable energy source due to its ability to be replenished and its historical use as fuel in some regions.
Step-by-step explanation:
The seedless plant that serves as a renewable source of energy is moss, specifically the dried peat moss known as Sphagnum. These plants are part of a group called bryophytes, which, unlike vascular plants, do not have an extensive system of xylem and phloem to transport water and nutrients. Instead, they absorb these directly through their surfaces. Sphagnum moss has been traditionally used as a fuel source and is considered a renewable energy resource because of its ability to regenerate quickly and its widespread availability.
Coal Formation and Use of Seedless Plants
Historically, seedless plants played a crucial role in forming deposits of coal from their decomposition in the Carboniferous period. They also have practical uses today, such as in soil conditioning and floral arrangements due to their moisture retention capabilities.
It's worth noting that in the most diverse group of seedless vascular plants, ferns take the lead and are considered the most advanced among their peers, which include liverworts, hornworts, and club mosses.