Answer :

smoking is very injurious to our health. it may cause cancer and several other respiratory problems. by xray repprt it has been found by smoking the lungs turn black. people when comes with contact of smoker also have these diseases
smoking is injurious to health because during smoking cigarette fumes makes the wall of the alveoli very gaunt and slender which leads to rupturing of alveoli this reduces the surface area of gases exchange and it leads to the heart that the heart has to pump more and more harder and this burdening of the heart may causes heart failure also it leads to many diseases like lung cancer .