Sponges reproduce asexually. The parent begins budding, when the buds grow to a certain point, they break off and drift with the oceans current to a new place, settle down into the sand or rocks, and start the cycle all over again. Since sponges are stationary organisms (meaning that they cannot travel on their own.) They rely on the oceans current to spread their species across the oceans.
Moon jellyfish reproduce during two different stages in their life cycle. During the medusa stage, they reproduce sexually by releasing sperm and eggs into the water. The method of reproduction used by jellyfish polyps is known as budding, and it does look like a plant growing a new bud for a flower. The polyp essentially clones itself. The clone buds out of the original polyp and detaches to float freely in the water.
