A-Level Biology Topic 8: Transport in Mammals | Heart, Blood, Circulation

Cambridge (CIE) AS Biology Your notes

Transport of Oxygen & Carbon Dioxide
Contents
Red Blood Cells, Haemoglobin & Oxygen
The Chloride Shift
Plasma & Carbon Dioxide
The Oxygen Dissociation Curve
The Bohr Shift




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, Red Blood Cells, Haemoglobin & Oxygen
Your notes
Red Blood Cells, Haemoglobin & Oxygen
The majority of oxygen transported around the body is bound to the protein
haemoglobin in red blood cells
Red blood cells are also known as erythrocytes
Each molecule of haemoglobin contains four haem groups, each able to bond with one
molecule of oxygen
This means that each molecule of haemoglobin can carry four oxygen molecules, or
eight oxygen atoms in total

Haemoglobin structure diagram




Haemoglobin proteins are made up of four subunits, each of which contains a region
called a haem group to which oxygen can bind
When oxygen binds to haemoglobin, oxyhaemoglobin is formed

Oxygen + Haemoglobin ⇌ Oxyhaemoglobin
4O2 + Hb ⇌ Hb4O 2


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