What is the function of polyp and medusa?
|Difference Between Medusa and Polyp|
|Can reproduce sexually as well as asexually||Exclusively sexual reproduction|
|Polyps can give rise to more polyps as well as medusae through budding||Medusae can only give rise to medusae|
What is the function of a polyp?
Polyps extend their tentacles, particularly at night, containing coiled stinging nettle-like cells or nematocysts which pierce and poison and firmly hold living prey paralysing or killing them. Polyp prey includes copepods and fish larvae.
What is the function of Gastrodermis?
Gastrodermis is the inner lining of the gastrovascular cavity. It is a single-layered tissue with gland cells and phagocytic nutritive cells. Food in the gastrovascular cavity is digested by enzymes that secretes from gland cells. The digested food is then engulfed by the nutritive cells.
What is the difference between a polyp and medusa body form?
Medusa is a mobile life cycle stage of the Cnidaria phylum, contracting with it muscular bell. Polyp have a tubular shape and are fixed at their base, with the mouth present at the other end of the tube facing the water. Medusa have a bell shape, with tentacles hanging down. Polyp do not have a manubrium.
What is the life cycle of obelia?
Structure. Through its life cycle, Obelia take two forms: polyp and medusa. They are diploblastic, with two true tissue layers—an epidermis (ectodermis) and a gastrodermis (endodermis)—with a jelly-like mesoglea filling the area between the two true tissue layers. They carry a nerve net with no brain or ganglia.
What is polymorphism in obelia?
The phenomenon of occurrence of an individual in two or more distinct morphological and functional forms. It occurs in the same species of an individual. Each individual member of Coelenterates is known as Zooid and they often units to form a colony which acts as a single unit (individual). …
How does the medusa stage fit into the life cycle of obelia?
Medusa are jellyfish bearing the characteristic bell shape and tentacles. At this stage, the Obelia medusa swim freely and reproduce sexually by releasing either eggs or sperm into the water. Upon fertilization, the resultant zygote develops into a free-swimming larva (plural: larvae) covered in cilia, or tiny hairs.
What is Metagenesis in obelia?
METAGENESIS The life cycle of Obelia represents a remarkable example of alternation of generation where the asexual and sessile phase of Obelia reproduces asexually by budding and gives rise to sexual and free-swimming medusa. This phenomenon of alternation between two diploid phases is termed as metagenesis.
How is it possible to tell the difference between the polyp of a Hydrozoan and that of an Anthozoan?
Anthozoan polyp: septate gut, stomodeum with siphonoglyphs, gastrodermal gonads, cellular mesoglea. Hydrozoan polyp is simple and lack other features. Both Anthozoan polyp and Scyphozoan medusa have gastrodermal gonads, divided gut, thick cellular mesoglea.
Which of the following is a polymorphic Coelenterate?
Physalia physalis is a species of cnidaria which are hydrozoids, which possess modified polyps such as gastrozooids, dactylozooids, and gonophores. Thus, the correct option is A, Physalia. Note: Coelenterate are aquatic invertebrates that show a wide range of polymorphism.
Do Coelenterates have Coelom?
All coelenterates are aquatic, mostly marine. The bodyform is radially symmetrical, diploblastic and does not have a coelom. The body has a single opening, the hypostome, surrounded by sensory tentacles equipped with either nematocysts or colloblasts to capture mostly planktonic prey.
What is Coelenterate polymorphism?
The occurrence of more than one type of structurally and functionally different individuals within a population is called polymorphism. The class Hydrozoa of phylum Coelenterata includes a large number of colonial species that contain more than one form of individuals which are called zooids.
Which group is commonly called as sea stick?
Cnidarian, also called coelenterate, any member of the phylum Cnidaria (Coelenterata), a group made up of more than 9,000 living species. Mostly marine animals, the cnidarians include the corals, hydras, jellyfish, Portuguese men-of-war, sea anemones, sea pens, sea whips, and sea fans.
Which is not a Coelenterate?
So, the correct answer is ‘Sea Cucumber/Lily’.
Which one of the following is a Coelenterate?
So, the correct answer is ‘Sea fan’
In which animal the polyp and medusa Both are found in?
What are the similarities between polyp and medusa?
Both polyp and medusa have a body wall, which surrounds an internal space called gastrovascular cavity. Both are aquatic organisms. Both have the mouth and are surrounded by tentacles.
How do polyps and medusae reproduce?
A medusa produces eggs or sperm, which are usually shed into the water; when an egg is fertilized, it develops into a swimming larva, which eventually settles and grows into a polyp. In addition to this elaborate means of reproduction, the polyp can form new polyps by budding.
What is Folip?
any growth or mass protruding from a mucous membrane. Polyps may be attached to a membrane by a thin stalk (pedunculated polyps), or they may have a broad base (sessile polyps).
What foods cause polyps?
fatty foods, such as fried foods. red meat, such as beef and pork. processed meat, such as bacon, sausage, hot dogs, and lunch meats.
Do polyps grow back?
Can polyps come back? If a polyp is removed completely, it is unusual for it to return in the same place. The same factors that caused it to grow in the first place, however, could cause polyp growth at another location in the colon or rectum.
Does everyone have polyps?
Anyone can develop colon polyps. You’re at higher risk if you’re 50 or older, are overweight or a smoker, or have a personal or family history of colon polyps or colon cancer. Colon polyps often don’t cause symptoms.
Can polyps go away naturally?
In premenopausal women, polyps often go away on their own and may require no additional treatment if you are not having symptoms and have no other risk factors. In some cases, uterine polyps are precancerous and need to be removed.
Why you shouldn’t get a colonoscopy?
The test can pose risks. Colonoscopy is a safe procedure. But occasionally it can cause heavy bleeding, tears in the colon, inflammation or infection of pouches in the colon known as diverticulitis, severe abdominal pain, and problems in people with heart or blood- vessel disease.
How fast do polyps grow?
Polyp Growth Rates Cancerous polyps tend to grow slowly. It is estimated that the polyp dwell time, the time needed for a small adenoma to transform into a cancer, may be on average 10 years (17). Evidence from the heyday of barium enema examinations indicates that most polyps do not grow or grow very slowly (18).
How often should you have a colonoscopy if polyps are found?
If your doctor finds one or two polyps less than 0.4 inch (1 centimeter) in diameter, he or she may recommend a repeat colonoscopy in five to 10 years, depending on your other risk factors for colon cancer. Your doctor will recommend another colonoscopy sooner if you have: More than two polyps.
What’s the difference between a polyp and a cyst?
Endometrial polyps are abnormal tissue growths within the endometrium, the inner lining of the uterus. Ovarian cysts are fluid-filled sacs on one or both ovaries that usually form during ovulation.
Do polyps grow back in uterus?
A uterine polyp can grow back after it has been removed. You may need treatment again. If you have another polyp, your doctor may suggest other treatments to prevent future uterine polyps.