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Each point: 1 Mark
$\begin{array}{cc}Arteries& Veins\\ 1.Bloodpressureinarteriesishigh& 1.Bloodpressureinveinsislow\\ 2.Arteriesendincapillaries& 2.Veinsstartfromcapillaries\\ 3.Distributesbloodtobodyorgans.& 3.Collectsbloodfrombodyorgans\end{array}$

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Process: 1 Mark
Instrument: 1 Mark
Working: 1 Mark
The walls of the chambers of the heart are made up of muscles. These muscles contract and relax rhythmically. The rhythmic contraction of muscles is followed by its relaxation. This constitutes aheartbeat.
The doctors use a stethoscope to listen to the heartbeat. It amplifies the sound of the heartbeats which makes it easier for thedoctors to listen.

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Location: 1 Mark
Chambers: 2 Marks
Blood circulation: 2 Marks
The heart is located in the chest cavity with its lower tip slightly tilted towards the left.
It has four chambers. The two upper chambers are called atria and the two lower chambersare called the ventricles.
The two types of blood circulation are pulmonary and the systemic circulation.
During the pulmonary circulation - The blood low in oxygen flows from the heart to the lungs and then oxygenated blood flows back to the heart. This blood rich in oxygenflows from heart to the rest of the body then back again to the heart. This is called systemic circulation.

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Naming: 1 Mark
Functions: 4 Marks
There are three types of blood cells-Red blood cells/erythrocytes (RBC), White blood cells/leucocytes (WBC) and platelets.
Red blood cells (RBCs)contain a red pigment called haemoglobin. haemoglobin has two main functions.
1. Haemoglobin binds withoxygen and transports it to all the parts of the body.
2.The presence of haemoglobin makes bloodappear red.
White blood cells(WBCs)helpto fight against the germs that may enter into our body.
Platelets help in the clotting of blood and prevent bleeding and loss of blood.

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Requirement: 1 Mark
Process: 2 Marks
Haemodialysis is required to treat kidney failure.
In hemodialysis, blood is passed through multiple tubes made up of a semipermeable membrane. During this passage, the waste products from the blood pass into the dialyzing fluid by diffusionand the purified blood is pumped back into the body.

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Each point: 1 Mark
$\begin{array}{ccc}\text{Sr.No.}& \text{Arteries}& \text{Veins}\\ 1& \text{They have thick}& \text{They have thin and}\\ & \text{elastic}& \text{less muscular walls.}\\ & \text{walls.}& \\ 2& \text{Direction of blood}& \text{Direction of blood flow}\\ & \text{flow is from the heart to}& \text{is from the organs of the body}\\ & \text{the organs of the body.}& \text{to the heart.}\\ 3& \text{They carry}& \text{They carry}\\ & \text{oxygenated blood}& \text{deoxygenated blood}\\ & \text{except in case of}& \text{except in case of}\\ & \text{pulmonary artery.}& \text{pulmonary vein.}\end{array}$

Answer: Option B. -> William Harvey 
:
B
WilliamHarveywas the first person to describe the circulation of blood in the body. He showed that arteries and veins form a complete circuit. The circuit starts at theheartand leads back to theheart. Theheart'sregular contractions drive the flow ofblood throughout the whole body.

Answer: Option B. -> False
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B
Arteries carry blood rich in oxygen,except the pulomonary artery which carries deoxygenated blood. Veins carry blood rich in carbon dioxide, except pulmonary veins which carry oxygenated blood. Hence the statement is incorrect.

Answer: Option C. -> Yellow
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C

• Blood is mainly composed of two components- plasma and blood cells.


• Plasma is yellow coloured fluid part of the blood.


• Blood cells are of three types- RBCs, WBCs and platelets.


• RBCs are red in colour due to haemoglobin and functions in transport of gases.


• White blood cells and platelets are colourless. WBCs are involved in defense mechanism, while platelets participate in blood clotting.


• So,if wehave only white blood cells in ourbody then the colour of the blood will be yellow due to colour of the plasma, since WBCs and plateletsare colourless.

Answer: Option B. -> thicker
:
B
Arteriesarelargebloodvessels that carrybloodfrom the heart to all parts of the body. For the blood to reach all parts of the body, heart pumps blood at a high pressure into the arteries. Veins, on the other hand carry deoxygenated blood from various body parts to the heart. In veins, the blood flows slowly. Hence, arteries have to be thicker than veins to withstand such high pressure.