Difference between octopus and polyp: when to use the term polyp and when octopus. Octopuses and polyps are two different animals, here is the definition and photos to see clearly!
Don’t worry, if you don’t know the difference between octopus and polyp you’re not alone. Even the restaurant and food distribution sector (see supermarkets!) often improperly use these names as synonyms. Octopus and polyp are not synonyms at all .
Let’s get this straight: if you read “octopus salad” or “octopus Luciana” at a restaurant, you are making a gross mistake. The octopus is the mollusk you are eating. Staying in the field of animal biology, the term octopus refers to a series of predominantly sessile animals such as corals!
In short, here is the difference: polyps are animals of the phylum cnidaria (the same as classic jellyfish), octopuses are animals belonging to the phylum molluscs (the same as squid and cuttlefish ).
Difference Between Octopus and Polyp in Animal Biology
The octopus is a mollusk (phylum mollusca) much loved in cooking. The octopus is not used in cooking!
Octopuses are cephalopod molluscs that live at depths of 200 meters. They are present in all seas and oceans. In the Mediterranean Sea, octopuses are fished from September to December in small sizes, while from May to July , more mature (and larger) octopuses are fished.
Polyps , on the other hand, are very different aquatic animals. They belong to the phylum Cnidaria (that is, the same as jellyfish ). The octopus can be solitary or colonial. Have you ever seen the movie “ Finding Nemo”? Well, Nemo is born in a rocky area full of anemones. The sea anemone is an example of a polyp. Among the many polyps in the animal kingdom, the most popular are:
- Sea Anemones
- Corals
- Madrepores
- Shapes of polyps and jellyfish
In some classes (hydrozoa, scyphozoa, and cubozoa) the polyp form represents one of the two life stages of the organism. In these cases, the animal spends one phase of its life cycle as a polyp and the other phase of life as a medusa . This should not surprise you at all if you think of the chrysalis (immobile, attached to a branch) and the butterfly.
Polyps do not live by inertia. Of course, they are mainly filter-feeding organisms (they retain organic particles suspended in the water and use them to feed themselves)… but they can also be hunters! The sea anemone, for example, secretes a sticky substance and can thus retain small fish or shrimp, feeding on them.
Symbiosis and photosynthetic polyps: the Great Barrier Reef
Some polyps are also photosynthetic, that is, in addition to feeding on organic matter filtered from the water, they are able to exploit wavelengths to carry out photosynthesis. This occurs due to a very close symbiosis that occurs between certain polyps and algae (called zooxanthellae).
If you think of coral reefs , you know that they are made up of colonial polyps that can extend for kilometers and kilometers. In Australia, the Great Barrier Reef extends for 345,000 square kilometers. The main fuel of the coral reef is light. Light is captured by photosynthetic pigments of zoochantellae (algae of the genus Symbiodinium). These algae live in close symbiosis with corals , stimulating their growth and promoting the construction of typical calcareous skeletons. Not only light, corals also absorb plankton and small doses of various nutrients.
Pathophysiology: Difference between polyp and octopus
The octopus is always an animal, a mollusk . In physiology, the term polyp can indicate an abnormal growth of tissue that protrudes toward a mucous membrane.
Nasal polyps can obstruct the upper airways causing stuffy nose and congestion. Very common are cases of polyps in the esophagus, colon, intestine but also in the cervix and uterus. Some polyps are benign tumors . Other polyps can be pre-malignant or develop in conjunction with a malignant neoplasm. When a polyp is malignant, in medicine it is called carcinoma or adenocarcinoma . That said, in the medical field when we generally speak of a polyp we are referring to an abnormal formation of a benign nature.
In context, if you hear about nasal polyp, endometrial polyp, or cervical polyp…. you will understand that it is a medical condition! On the contrary, if you are at a restaurant and you hear about octopus salad , you know very well that they are making a gross mistake.