Qstnid -I-7-a-blood And Lymph (B) Open And Closed System Of Circulation (C) Systole And Diastole (D) P-wave And T-wave - 18: Body Fluids And Circulation

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#7-a

Blood and Lymph
(b) Open and Closed system of circulation
(c) Systole and Diastole
(d) P-wave and T-wave

Ans : Blood and lymph

	Blood		Lymph
1.	Blood is a red-coloured fluid that contains RBCs.	1.	Lymph is a colourless fluid that lacks RBCs.
2.	It contains plasma, RBCs, WBCs, and platelets. It also contains proteins.	2.	It contains plasma and lesser number of WBCs and platelets. It lacks proteins.
3.	Blood transports nutrients and oxygen from one organ to another.	3.	Lymph plays a role in the defensive system of the body. It is a part of the immune system.

(b) Open and closed systems of circulation

	Open system of circulation		Closed system of circulation
1.	In this system, blood is pumped by the heart, through large vessels, into body cavities called sinuses.	1.	In this system, blood is pumped by the heart, through a closed network of vessels.
2.	The body tissues are in direct contact with blood.	2.	The body tissues are not in direct contact with blood.
3.	Blood flows at low pressure. Hence, it is a slower and less efficient system of circulation.	3.	Blood flows at high pressure. Hence, it is a faster and more efficient system of circulation.
4.	The flow of blood is not regulated through the tissues and organs.	4.	The flow of blood can be regulated by valves.
5.	This system is present in arthropods and molluscs.	5.	This system is present in annelids, echinoderms, and vertebrates.

	Systole		Diastole
1.	It is the contraction of the heart chambers to drive blood into the aorta and the pulmonary artery.	1.	It is the relaxation of the heart chambers between two contractions. During diastole, the chambers are filled with blood.
2.	Systole decreases the volume of the heart chambers and forces the blood out of them.	2.	Diastole brings the heart chambers back into their original sizes to receive more blood.

(d) P-wave and T-wave

	P-wave		T-wave
1.	In an electrocardiogram (ECG), the P-wave indicates the activation of the SA node.	1.	In an electrocardiogram (ECG), the T-wave represents ventricular relaxation.
2.	During this phase, the impulse of contraction is generated by the SA node, causing atrial depolarisation.	2.	During this phase, the ventricles relax and return to their normal state.
3.	It is of atrial origin.	3.	It is of ventricular origin.

#7-b

Open and Closed system of circulation

Ans : Open and closed systems of circulation

	Open system of circulation		Closed system of circulation
1.	In this system, blood is pumped by the heart, through large vessels, into body cavities called sinuses.	1.	In this system, blood is pumped by the heart, through a closed network of vessels.
2.	The body tissues are in direct contact with blood.	2.	The body tissues are not in direct contact with blood.
3.	Blood flows at low pressure. Hence, it is a slower and less efficient system of circulation.	3.	Blood flows at high pressure. Hence, it is a faster and more efficient system of circulation.
4.	The flow of blood is not regulated through the tissues and organs.	4.	The flow of blood can be regulated by valves.
5.	This system is present in arthropods and molluscs.	5.	This system is present in annelids, echinoderms, and vertebrates.

#7-c

Systole and Diastole

Ans : Systole and diastole

	Systole		Diastole
1.	It is the contraction of the heart chambers to drive blood into the aorta and the pulmonary artery.	1.	It is the relaxation of the heart chambers between two contractions. During diastole, the chambers are filled with blood.
2.	Systole decreases the volume of the heart chambers and forces the blood out of them.	2.	Diastole brings the heart chambers back into their original sizes to receive more blood.

#7-d

P-wave and T-wave

Ans : P-wave and T-wave

	P-wave		T-wave
1.	In an electrocardiogram (ECG), the P-wave indicates the activation of the SA node.	1.	In an electrocardiogram (ECG), the T-wave represents ventricular relaxation.
2.	During this phase, the impulse of contraction is generated by the SA node, causing atrial depolarisation.	2.	During this phase, the ventricles relax and return to their normal state.
3.	It is of atrial origin.	3.	It is of ventricular origin.