Does Obelia have Medusa?
Does Obelia have Medusa?
Obelia is a genus of hydrozoans, a class of mainly marine and some freshwater animal species that have both polyp and medusa stages in their life cycle.
How does Obelia produced Medusa?
The polyp asexually produces medusae, or jellyfish. Obelia medusae release sperm or eggs into the surrounding water, and the resulting ciliated larva eventually metamorphoses to produce a branching colony of polyps.
How many zooids are present in Obelia?
The Obelia is a trimorphic colony, that is, having three kinds of zooids which are as follows: 1. Polyps or hydranths (nutritive zooids);
How do you identify obelia medusa?
Description: The Obelia dichotoma medusa is a small hydromedusa with the bell diameter greater than its height. It has no ocelli. The manubrium is short. More than 16 unbranched tentacles, all about the same size, are distributed evenly along the margin of the bell.
What is the advantage of the medusa form?
The Medusas Stage allows for the cnidarians to actively move using their long tentacles to pull the water into themselves to gain nutrients.
Do corals have a medusa stage?
The class Anthozoa includes all cnidarians that exhibit a polyp body plan only; in other words, there is no medusa stage within their life cycle. Examples include sea anemones, sea pens, and corals, with an estimated number of 6,100 described species.
What is difference between polyp and medusa?
Sessile structures are called polyps while the swimming forms are called medusa. The key difference between polyp and medusa is that polyp is a fixed, cylindrical structure, representing the asexual stage and medusa is a free swimming, umbrella-like structure, representing the sexual stage.
How many gonads are present in medusa?
F: Mature female medusa with four gonads.
Why obelia is called Trimorphic?
It is called trimorphic because it has 3 stages in its life and these are polyp medusa and blastostyle.
What’s the difference between medusa and polyp?
Polyp is a sessile life stage of the cnidaria phylum whereas medusa is totally opposite i.e they have a mobile life cycle stage of the cnidaria phylum. 2. Morphology of Polyp and Medusa: Morphological features of polyp are tubular in shape and they are fixed at their base.