The Respiratory System

at a Glance

Jeremy Ward, Jane Ward and Richard Leach

Multiple Choice: Chapter 8 Carriage of oxygen

Question 8.1. Haemoglobin

a is composed of four identical subunits
b has iron at the centre of haem groups which must be in the ferrous form to bind O2
c binding of oxygen is reduced in the presence of high Pco2 because CO2 and O2 compete for the same binding sites on haemoglobin
d variants (such as fetal haemoglobin) often differ from normal adult haemoglobin in the precise structure of the haem group.