Question

Haemoglobin is present in _____ cells.

Answer 1

Hemoglobin is Greek word which means 'haem' as "blood" and 'globulin' means "ball or sphere. The abbreviated form of haemoglobin is 'Hb'. Hemoglobin is iron- containing oxygen- transport metalloprotein.

Complete answer:
Hemoglobin develops in cells of the bone marrow that on maturing become red blood cells (RBC). When these red cells die or aged hemoglobin present in between them is broken up into iron it goes back into the bloodstream or is transported to the bone marrow by proteins called transferrins and reused again in the production of new red blood cells. Haemoglobin is the protein molecule in red blood cells (RBC) that carries oxygen from the lungs to the body's tissues and takes up the carbon dioxide from the tissues to the lungs.
Haemoglobin is made up of four protein molecules which are globin chains that are connected together and one iron molecule. Heme which presents for only 4 percent of the weight of the molecule, is composed of a ringlike structural organic compound known as a porphyrin to which an iron atom is attached. It is the iron atom that binds up with oxygen molecules as the blood travels between the lungs and the tissues. Haemoglobin plays a very important role that gives red color to the blood and also plays a very important role to maintaining shape of the cells. Red blood cells are naturally round with a circular depression in the center making them resemblance with dough.
Red blood cell is red in colour due to the presence of Hemoglobin.

Hence Hemoglobin is present in Red blood cells.

Note: Hemoglobin forms an unstable reversible bond with oxygen which means upon maturity or after death of the cells molecules of haemoglobin separate out and reuse for other molecules or we can say go into another pathway of the body circulation. When it is in an oxygenated state it is called oxyhemoglobin and is bright red and when in the reduced state it is called deoxyhemoglobin and is purple-blue colour appearance.