What are the components of blood?
There are four components of blood:
(i) Plasma is a liquid part of blood which is yellowish in colour and contain 90% water. It contains food, enzymes, wastes and proteins etc
(ii) Red blood cells are disc shaped cells containing red coloured pigment called haemoglobin in it. Haemoglobin helps in transportation of oxygen.
(iii) White blood cells are the fighting cells which protect us against bacteria and foreign materials causing infections.
(iv) Platelets help in clotting of the blood
Fill in the blanks :
(i) The blood from the heart is transported to all parts of the body by the _____________
(ii) Haemoglobin is present in ___________ cells.
(iii) Arteries and veins are joined by a network of ___________ .
(iv) The rhythmic expansion and contraction of the heart is called ___________
(v) The main excretory product in human beings is ___________
(vi) Sweat contains water and .
(vii) Kidneys eliminate the waste materials in the liquid form called .
(viii) Water reaches great heights in the trees because of suction pull caused by .
Choose the correct options:
(a) In plants, water is transported through
(i) Xylem (ii) Phloem (iii) Stomata (iv) Root hair
(b) Water absorption through roots can be increased by keeping the plants
(i) In the shade (ii) in dim light (iii) under the fan (iv) covered with a polythene bag