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प्रश्न
Give reason:
Valves are present in the veins.
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उत्तर
- The main function of the valves in veins is to prevent backflow of blood.
- They are thin walled with semilunar valves to prevent backward flow of blood.
- Blood in the arteries, after being pumped by the heart, are under much higher pressure than blood in veins so there is no need for valves in arteries to prevent back flow.
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संबंधित प्रश्न
Fill in the blank with suitable word given below:
The two lower chambers of the heart are called ___________.
Draw the diagram of the Position of valves in the human heart.
Short answer question.
Describe valves of human heart.
‘Heart of heart’ is called ______
Why are the walls of the left ventricle thicker than the other chambers of the heart?
The blood does not flow back into the ______ when mitral valve closes.
______ is the nodal tissue located in the lower-left corner of the right atrium.
The inner surface of the ventricle is thrown into series of irregular muscular ridges called ______
Explain the structure of heart.
Fill in the blanks of the following paragraph using just two words – arteries and veins.
___(a)___ carry oxygen-rich blood from the heart to all parts of the body and ___(b)___ carry carbon dioxide-rich blood from all parts of the body back to the heart. ___(c)___ have thin walls and ___(d)___ have thick elastic walls. Blood flows at high pressure in ___(e)___. Valves are present in ___(f)___ which allow blood to flow only towards the heart. ___(g)___ divide into smaller vessels. These vessels further divide into extremely thin tubes called capillaries. The capillaries join up to form ___(h)___.
