The correct answer is option B. Higher levels of haemoglobin
A higher level of the haemoglobin allows the organism to survive in low oxygen condition. The low oxygen level decreases the amount of oxygen delivered to the cells, to cope up this condition, there is an increase in the haemoglobin content. The increased haemoglobin concentration allows the delivery of the sufficient amount of oxygen, as the number of haemoglobin increase, the capacity of oxygen carried to the cell is increased.
The right answers are on the attached image.
Baroreflex is a reflex triggered when a baroreceptor is stimulated. In the human body, baroreceptors are found in the carotid sinuses and the sinus of the aorta. These receptors are stimulated during changes in blood pressure. Baroreceptors are sensitive to the stretching of blood vessels.
As blood pressure rises, baroreceptors transmit nerve impulses to the vasomotor center of the medulla oblongata, which is then inhibited. This results in vasodilatation of the blood vessels to reduce blood pressure.
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