Question

(a) Mention any two components of blood.

(b) Trace the movement of oxygenated blood in the body.

(c) Write the function of valves present in between atria and ventricles.

(d) Write one structural difference between the composition of artery and veins.

OR

(a) Define excretion.

(b) Name the basic filtration unit present in the kidney.

(c) Draw excretory system in human beings and label the following organs of excretory system which perform the following functions :

(i) forms urine.

(ii) is a long tube which collects urine from kidney.

(iii) Store urine until it is passed out.

Answer 1

(a) Red blood cells, white blood cells and platelets are the components of blood.

(b) The oxygenated blood goes into the left atrium from there it goes to the left ventricle and then to all the body organs.

(c) Valves prevents the backflow of blood from the ventricles to the atrium.

(d) Walls of arteries are thick and they carry oxygenated blood whereas walls of vein are thin and they carry deoxygenated blood.

OR

(a) The process of removing toxic waste from the human body is called excretion.

(b) Nephron is the basic filtration unit present in the kidney.

(c)