What is the difference between hydrozoans and Scyphozoans?

What is the difference between hydrozoans and Scyphozoans?

Hydrozoans have a sexual medusa stage and a nonsexual polyp stage, whereas scyphozoans have a shortened asexual polyp stage. Hydrozoans have velum at the medusa that aids in propulsion, but scyphozoan polyps lack this velum.

How are hydrozoans different from other cnidarians?

They are distinguished from other groups by their complex life cycle, by the growth of medusae from buds rather than strobilae or from metamorphosis, by the presence of a velum inside the bell of the medusa, and by the production of gametes from ectodermal, rather than endodermal, tissue.

What are some differences between Scyphozoans and Cubozoans?

Key Points. Cubozoans differ from Scyphozoans in their arrangement of tentacles; they are also known for their box-shaped medusa. Out of all cnidarians, cubozoans are the most venomous. Hydrozoans are polymorphs, existing as solitary polyps, solitary medusae, or as colonies.

Are hydrozoans polyps or medusa?

Most hydrozoans alternate between a polyp and a medusa stage — they spend part of their lives as “jellyfish” which are hard to distinguish from scyphozoan jellyfish. A great many hydrozoans are also colonial.

What makes hydrozoans different from true jellies & True Coral?

Unlike true corals which consist of many cells of an individual animal, Hydrozoan corals consist of individual members called Zooids that together function as a colonial animal.

How do polyps and medusae differ?

Polyp are sessile while medusa are mobile. Polyp present a tubular shape with the mouth facing the water upwards,while medusa present a bell shape with the mouth facing the water downwards. Polyp do not have a manubrium, while medusa of the class Hydrozoa present a tube hanging down from the bell known as manubrium.

What’s the difference between Anthozoans and Medusozoans?

The Anthozoa contain only sessile polyp forms, while the Medusozoa include species with both polyp and medusa forms in their life cycle.

What makes hydrozoans different from true Jellies & True Coral?

What makes Anthozoa unique?

Anthozoans have special glands that secrete digestive fluids. Some have been known to digest extremely large fish. Anthozoans are found around reefs and shallow waters. Since they help build coral reefs they have been valuable to scientists in learning about the past climates of certain regions.

Is a jellyfish a polyp or medusa?

Throughout their lifecycle, jellyfish take on two different body forms: medusa and polyps. Polyps can reproduce asexually by budding, while medusae spawn eggs and sperm to reproduce sexually. Learn more about the lifecycle and reproduction of jellyfish.

What is called a polyp and medusa?

There are two basic cnidarian body shapes: a polyp form, which is attached to a surface; and an upside-down free-floating form called a medusa. Some cnidarians change form at different phases of their life cycle, while others remain in one form for their entire life.

What is the difference between the medusa and polyp stages in the life cycle?

Most of the Cnidarian classes utilise polyp and medusa as two stages of their life cycle. Polyps are sessile and asexually reproduce by budding. But, medusa reproduces sexually by producing sperms and eggs. The key difference between polyp and medusa is that polyp is sessile whereas medusa is free-swimming.

  • October 17, 2022