11. Aerobic oxidation is caused by

1. 1. aerobic batteries in presence of excess of oxygen

   
   
   

   2. anaerobic bacterias in presence of insufficient oxygen

   
   
   

   3. aerobic bacterias in the absence of oxygen

   
   
   

   4. both anaerobic and aerobic bacterias in any condition

   
   
   

---

1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: A

   NA

---

12. Which one of the following was used as a chemical weapon in the first world war ?

1. 1. Carbon monoxide

   
   
   

   2. Hydrogen cyanide

   
   
   

   3. Mustard gas

   
   
   

   4. Water gas

   
   
   

---

1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   NA

---

---

13. Jaundice in human beings affects which of the body part ?

1. 1. Liver

   
   
   

   2. Eye

   
   
   

   3. Skin

   
   
   

   4. None of these

   
   
   

---

1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: A

   NA

---

14. Man dies in the atmosphere of CO, because it

1. 1. dries up the blood

   
   
   

   2. combines with O₂ present in the body

   
   
   

   3. reduces the organic matter of tissues

   
   
   

   4. combines with the haemoglobin of blood, thereby making the later incapable of absorbing O₂

   
   
   

---

1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   NA

---

---

15. Lead in water can cause

1. 1. eye disease

   
   
   

   2. arthritis

   
   
   

   3. kidney damage

   
   
   

   4. hair falling

   
   
   

---

1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   NA

---