When the affinity of $O_2$ and $CO_2$ for haemoglobin is compared,it is:

The major fraction of $CO_2$ released during cellular respiration is transported by the blood to the lung capillaries as:

How is $CO_2$ transported from tissues to the respiratory surface?

Although much carbon dioxide is carried in blood,yet blood does not become acidic because

Haemoglobin $(Hb)$ transports oxygen from the lungs to tissues. The partial pressure of oxygen in the lungs is different from that in the tissues. Each $Hb$ can bind to up to four oxygen molecules. Suppose we have an equal number of $Hb$ and oxygen molecules,and all the oxygen molecules are in a bound form. Then,which of the following is true?

Explain the oxygen dissociation curve. Explain the factors required for the transport of $O_2$ by it.