question_answer 7)

Write the differences between (a) Blood and lymph (b) Open and closed system of circulation (c) Systole and diastole (d) P-wave and T-wave  

Answer:

 (a) Differences between Blood and Lymph. Refer to Ans. 5 of This chapter (see above). (b)      Differences between Open and Closed Circulatory System  

S.N.	Open Circulatory System	Closed Circulatory System
1.   2.       3.	It is present in arthropods and molluscs, Blood pumped by heart passes through large vessels into open spaces or body cavities called sinuses. Flow of blood is not regulated precisely,	It is present in annelids and chordates. Blood pumped by the heart is circulated through a loosed network of blood vessels.   It is more advantageous as the blood flow is more precisely regulated;

(c)       Differences between Systole and Diastole  

S.N.	Systole	Diastole
1.     2..       3.	The contraction of the musclesof auricles and ventricles is called systole. It increase the ventricular pressure causing the closure of tricuspid and bicuspid valves due to attempted back flow of blood into atria, Systolic pressure is higher and occurs during ventricular contraction.	It is the relaxation of atria and ventricle muscle.   The ventricular pressure falls causing the closure of semilunar values which prevent back flow of blood into the ventricle. Diastolic pressure is lower and occurs during ventricular expansion.

(d)      Differences between P-wave and T-wave  

P-wave	T-wave
The P-wave represents the electrical excitation (or depolarisation) of the atria, which leads to the contraction of both the atria,   marks the end of systole.	The T-wave represents the return of the ventricles from excited to normal state (repolarisation). The end of the T-wave