What is the function of the Hydranth?

A hydranth, is encased and protected in a transparent vase-like hydro-theca. It captures minute prey by using its tentacles which contain batteries of nematocysts. The coelenteron of the hydranth communicates with the cavity of the hydrocaulus and thus the absorbed food is distributed to the entire colony. What is polyp or hydranth?
Polyp or hydranth (nutritive zooids): This nutritive zooid of the colony is also known as gastrozooids or trophozooid. It is yellow in color, radial symmetrical and cylindrical in shape. They are specialized for capture, ingestion and digestion of food. Each hydranth is closely similar in structure to that of hydra.

What is Hydrotheca?

: a cup-shaped extension of the perisarc in hydroids of the group Leptomedusae that surrounds and protects the hydranths when they are contracted. What is the function of the Hydranth in obelia?
The hydranths are feeding polyps, they feed by capturing minute animals and larvae. Towards the base of the hydrocaulus in the axils of the polyps, are reproductive polyps called blastostyles.

Is sea anemone a polyp or medusa?

Unlike jellyfish, sea anemones do not have a medusa stage in their life cycle. A typical sea anemone is a single polyp attached to a hard surface by its base, but some species live in soft sediment and a few float near the surface of the water. Are polyps benign?

Polyps are benign (non-cancerous) growths, but cancer can start in some types of polyps. These polyps can be thought of as pre-cancers, which is why it is important to have them removed.

Frequently Asked Questions(FAQ)

What are the functions of polyp of Obelia?

Obelia polyps (= zooids) are dimorphic, there being two types in the colony. Gastrozooids are responsible for feeding, which they accomplish by capturing and ingesting zooplankton. Gonozooids are reproductive and produce medusae by asexual budding.

What nutrients are zooids?

Hydranths or polyps are nutritive zooids. They have a body shaped like a vase with mouths and tentacles. Enclosing the polyp is a pericardial covering which is called hydrotheca. Hydranths are feeding polyps that capture very small larvae and insects to feed themselves.

What is Monostichodont?

In leeches, having only one row of teeth in each jaw.

What is Hydocaulus in zoology?

(Science: zoology) The hollow stem of a hydroid, either simple or branched. Last updated on July 21st, 2021.

What is Medusa of Obelia?

What are the structural difference between Obelia and jellyfish?

Structure of the Dominant Phase of the Life Cycle Moreover, the polyp phase of Obelia has a vase-shaped body while the dominant phase of jellyfish has a bell-shaped body. Thus, this is one of the major structural differences between Obelia and jellyfish.

Why is Obelia called Trimorphic?

It is called trimorphic because it has 3 stages in its life and these are polyp medusa and blastostyle.

Is anemone a coral?

Anemones are not a type of Soft Coral Anemones are cniderians like jellyfish. They are all fleshy and can sting. While coral comprise of colonies of several cellular organisms with rich calcium shells, anemones are a single organism, and not a colony of several polyps.

Can you eat sea anemones?

Anemones were enjoyed and considered a delicacy by many, especially elders. If one was served an anemone, it was to be eaten in its entirety, otherwise, it was said that the person would become a widower [1, 3].

What happens if you touch an anemone?

Luckily, most anemones don’t have large enough stinging cells to affect humans, but there are some to be wary of. If you have ever touched a small anemone, the sticky feeling you may have felt is caused by those tiny harpoons as the anemone tries to eat your finger.

Is a 10 mm polyp considered large?

The larger the polyp becomes, the bigger the risk of it developing into colon cancer. That risk increases significantly if the polyp is greater than 10 mm (1 cm); research has shown the larger a colon polyp becomes, the more rapidly it grows.

Why do people get polyps?

Mutations in certain genes can cause cells to continue dividing even when new cells aren’t needed. In the colon and rectum, this unregulated growth can cause polyps to form. Polyps can develop anywhere in your large intestine.

Can a doctor tell if a polyp is cancerous by looking at it?

During a colonoscopy all polyps are removed regardless of their size or how they look. Only then can they be evaluated for any problems. In most cases they are benign, but only by testing them can your physician determine if they are harmless, in the pre-cancerous state, or malignant.

What kind of polyps do you find on an Obelia colony?

Obelia. The colonial sessile form of Obelia geniculata has two types of polyps: gastrozooids, which are adapted for capturing prey, and gonozooids, which asexually bud to produce medusae.

What is Obelia polyp?

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. Hydrozoa belongs to the phylum Cnidaria, which are aquatic (mainly marine) organisms that are relatively simple in structure. Obelia is also called sea fur.

How many points are correct about Obelia?

Question	(i) Radial symmetrical (ii) Diploblastic (iii) The cellular level of organization (iv) Digestion is intracellular only (v) Exhibit two basic body forms called polyp and medusa. How many points are correct about Obelia?
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Which of the following is feeding Zooids in Obelia?

– In Obelia, the chitinous coating or perisarc enclosing the hydranths forms a supporting cup called a hydrotheca. Each hydrant terminates in a cone known as a hypostome bearing the mouth and surrounded by a ring of about 24 tentacles. So, the correct answer is ‘Hydranths’.

What are Zooids in cnidaria?

Zooids are the individual polyps present in the colonies of hydroids. Individual zooids in the colony perform various different tasks such as reproductive polyps are called gonozooids, feeding individuals are called gastrozooids.