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Tissues — Science STD 9 — Question

Gujarat BoardEnglish MediumSTD 9ScienceTissues5 Marks
Question
Describe the composition and functions of blood
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Answer

Blood is a fluid connective tissue. There are three types of blood corpuscles:
  1. RBC's or Erythrocytes: These are bi-concave, denucleated, disc like. They contain red coloured respiratory pigment called haemoglobin that helps in the transportation of oxygen.
  2. WBC's or leucocytes: These are irregular, amoeboid, phagocytic cells with one to many lobed nucleus. These cells protect the body against the diseases by producing antibodies.
  3. Blood platelets or thrombocytes: These are spindle shaped cells which help in the clotting of blood.
Functions of blood:
  1. It transports nutrients, hormones and vitamins to the tissues and transports excretory products from the tissues to the liver and kidney.
  2. The RBCs carry oxygen to the tissues for the oxidation of food stuff.
  3. WBCs fight disease by engulfing and destroying foreign bodies.

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