Question

If you plot an oxygen-hemoglobin saturation curve for a mammal and want to add a curve for myoglobin, you would have to put place it _________ the o2-Hb curve. This reflects myoglobin's affinity for oxygen.

A. over; similiar B. to the left of; increased C. To the right of; decreased D. to the right of; increased

In mammals, the major control of ventilation is blood_______and in fish, the major control of ventilation is blood________.

A. Co2 level; oxygen level B. Oxygen level; oxygen level C. Co2 level; pH D. Oxygen level; Co2 level

Answer 1

Ans1- If you plot an oxygen-haemoglobin saturation curve for a mammal and want to add a curve for myoglobin, you would have to place it to the right of oxygen-heamoglobin curve. This reflects myoglobin affinity for oxygen increased.

Reason-The saturation curve for myoglobin shows a rapid oxygen concentration -dependent saturation, which means that in low oxygen concentration also the ability of myoglobin to saturate is more than that of haemoglobin .

Note-The myoglobin can be fully saturated whereas,the haemoglobin requires high oxygen tention which is available in fetal blood only . Also when you compare the adult haemoglobin dissociation curve and fetal dissociation curve, you will observe that the fetal curve is to the left side of the adult curve, this signifies that the fetal haemoglobin saturates more easily than the adult one. This plays an important role for oxygen exchange between the fetus and the mother.

Ans2- In mammals the major control of ventilation is blood CO₂level and in fish,the major control of ventilation is blood oxygen level.

Reason- The receptors in our body (mammals)are designed is such way that, they get sensitized in response to change in CO₂level in the blood stream . After stimulated by high CO₂level, this receptors send signal to the respiratory centers situated in the brain stem which further send signal to the inspiratory group of muscle to inhale. During exhalation CO₂is released lowering it's level in blood again CO₂is produced by body tissue and the chain goes on.