Advertisements
Advertisements
प्रश्न
Give reason, why a matured mammalian erythrocyte lacks nucleus and mitochondria?
Advertisements
उत्तर
A matured mammalian erythrocyte lacks a nucleus and mitochondria. The lack of a nucleus
increases the surface area-volume ratio of RBCs, thus increasing the area for oxygen absorption.
Also, the lack of a nucleus reduces the size of the cell, making it easy to flow through the blood
vessels and more cells can be accommodated in a small area.
The lack of mitochondria implies that the cell does not use any oxygen absorbed for respiration,
thus increasing the efficiency of the cell to transport oxygen as all the oxygen absorbed is
transported without any loss.
संबंधित प्रश्न
Angina pectoris is due to
Name the following:
The phase of the cardiac cycle in which the auricles contract.
Give reason for the following:
The walls of the left ventricle are thicker than the walls of all other chambers.
Give reason for the following:
Only the veins and not the arteries are provided with valves.
Give reason for the following:
Atrial wall is less muscular than the ventricular wall.
Given diagram shows a simple diagram of the circulation of blood in a mamma showing the
main blood vessels, the heart, lungs and body tissues. The blood vessel, labelled 6, contains
deoxygenated blood and the valve leading to it has three semi-lunar pockets.

(a) Name the blood vessels and organs marked by numbers 1 to 8.
(b) What is meant by the term ‘double circulation’ of blood in mammals?
(c) what is diastole?
[There is an “error” in the diagram. According to the usual practice the pulmonary (lung)
circulation is shown upward and the systemic downward, but here it is reversed].
Define the Veins.
Name the Following
Oxygen is transported by the blood in the form of
Circulation is carried out by ______ in higher animals.
______ is an agranulocyte.
