The majority of carbon dioxide produced by our body cells is transported to the lungs as

Reduction in $pH$ of blood will

Identify the wrong statement with reference to transport of oxygen.

If $ppCO_2$ is high and pH is low,then it will result in:
$i$. increase in affinity of haemoglobin for $O_2$
$ii$. decrease in affinity of haemoglobin for $O_2$
$iii$. oxygen dissociation curve shifts to left
$iv$. causes release of $O_2$ for diffusion into tissue cells
$v$. $H^+$ and $HCO_3^-$ ions combine to form carbonic acid

Which of the following factors contribute to the binding of $O_2$ with hemoglobin?

To which part of $Hb$,$CO_2$ binds?