Question

Haemoglobin pigment is present in the blood of certain
A) Snails
B) Annelids
C) Echinoderms
D) Arthropods

Answer 1

Hint:Haemoglobin is a protein with four subunit globin proteins which is present in the red blood cells (RBCs) of almost all vertebrates and is responsible for the transport of oxygen from the lungs or gills to all the other parts of the body.

Complete answer:
Let us look at each option one by one.
Snails are shelled gastropod molluscs which contain the copper containing compound hemocyanin for oxygen transport in the body. Only a certain type of freshwater snails called the trumpet snails have a high molecular weight of extracellular hemoglobin. Therefore, this option is incorrect.

Annelids are a phylum of ringed worms which utilize extracellular haemoglobin for the transport of oxygen in the body. The haemoglobin in annelids slightly differs from the vertebrate haemoglobin and can weigh almost 46 times the weight of the vertebrate haemoglobin. Therefore, this is the correct option.

Echinoderm refers to organisms belonging to the phylum echinodermata. These organisms do not have a true heart and often lack respiratory pigments like haemoglobin. Therefore, this option is incorrect.

Arthropods are organisms belonging to the phylum arthropoda. These organisms do not possess blood instead they have a fluid called hemolymph for the transport of nutrients in the body. Since these organisms exchange gases through their skin and trachea, they do not require pigments like haemoglobin for transporting oxygen. Therefore, this option is incorrect.

Thus, the correct answer is option (B) Annelids.

Note: Haemoglobin as mentioned earlier contains four subunit proteins (two alpha and two beta). To facilitate transport of a high percentage of oxygen, vertebrates have their red blood cells specialized such that they lack nucleus and have flexible cell membranes which enable in the transport of oxygen to the deepest niches of the body.