Question

In which of the following haemocyanin pigment is found?
A. Higher invertebrates
B. Echinodermata
C. Nematode
D. Annelida

Answer 1

Hint: Haemocyanin pigment is made up of haem and cyanine which is copper. So, just as haemoglobin binds with oxygen and transports it inside the body, copper atoms in hemocyanin bind with oxygen and transport them inside the body.

Complete answer:
> Haemocyanin pigment transports oxygen throughout the bodies of some of the invertebrates. When the pigment is deoxygenated it has no colour but as soon as it gets oxygen it turns blue.
Animal kingdom has various classification based on the level of organisation (cellular or tissue), symmetry, presence of body cavity or presence of a vertebral column. This classification is also a result of evolution that has taken place over the years.
> Phylum Echinodermata, higher invertebrates and Phylum Annelida come under tissue level of organisation and have a true body cavity. The Phylum Nematoda has a pseudocoelom, meaning a false body cavity.
Echinodermata have an open and reduced circulatory system. There is no heart and usually there is absence of a respiratory pigment.
> Nematodes that lack any type of circulatory system exchange materials with the help of their skin. They lack any
> Phylum Annelida, such as Earthworm and Leeches, have red-coloured pigment (that is haemoglobin), Green-coloured pigment or no pigment at all. They usually have a closed or partially opened circulatory system.

Therefore, the correct answer would be (A). Higher invertebrates contain haemocyanin pigment.

Note: Hemocyanin pigment is only found in phylum Mollusca and Annelida. The oxygen carrying capacity of Hemocyanin is less than that of haemoglobin. The examples of Echinoderms are starfish, sea urchins and sea cucumbers. Examples of Nematodes are the worms such as Ascaris and pinworm. Phylum Mollusca (for example: Octopus) has haemocyanin pigment.