Question

B. Fill in the blanks :
_______defined the body against infection.
2. The rhythmic_______and_______
of heart is called heartbeat.
3._________are the most important organ of the human excretory system.
4._________are the reproductive parts of a plant.​

Answer 1

• WBC

• a.SA node (sinoatrial node)

        b.AV node (atrioventricular node).

• Kidneys.
• a.Stamens are the reproductive parts of flowers

Answer 2

Answer:

a) WBC

b) contraction and relaxation

c) Kidneys

d) Flowers

Explanation:

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