Q1. Fill in the blanks.
a. Saliva excreted by salivary glands starts breaking the food in the mouth.
b. Molars are the biggest of all teeth which helps to grind the food.
c. The mouth has teeth, tongue and salivary glands.
d. The air passes through windpipe to reach the lungs.
e. The sense organs pass information to brain.
f. Veins bring deoxygenated blood to the heart.
g. Arteries carry the oxygenated blood from the heart to the different parts of the body.
h. Teeth, mouth, food pipe, stomach and small and large intestine make the digestive system.
i. The lungs supply oxygen to the body.
a. Liver makes bile juice which helps in breaking fats in our food. True
b. All the food is digested in the stomach. False
c. Large intestine throws out undigested food which is mainly fibre/roughage. True
d. Canine teeth help in cutting and biting the food. False
e. Liver and pancreas help in the process of digestion. True
f. The brain helps us to think. True
Q3. Name the juice secreted by the liver.
Which juice is secreted by liver?
What is the juice secreted by the liver called?
Ans. Bile juice
Q4. What is the largest organ in the human body?
Ans. Skin is the largest organ in the human body.
Q5. Which organ pumps blood to every part of our body?
Q6. Where does absorption of food take place?
Ans. Small intestine
Q7. Who tells the body parts what to do?
Ans. Our brain collects information from our surroundings and then tells the body parts to move.
Q8. What is the function of saliva in the mouth?
Ans. It breaks down the food and makes it soft and moist.
Q9. List some healthy habits for proper functioning of the digestive system.
Ans. Some healthy habits that help in proper functioning of the digestive system are:
a. Drinking plenty of water
b. Eating at a proper time
c. Chewing the food properly
Q10. Where does the air go that we breathe in?
What happens to the air we breathe in?
What happens to the air that enters our body?
Ans. From the nose, air enters the windpipe. It passes through the bronchi and goes into the pair of lungs in our chest. The lungs contain many blood capillaries. Oxygen in the air enters the blood capillaries and gets dissolved in the blood. It is then taken to the different parts of the body. This oxygen combines with our food and releases energy.
Q11. Name the organs of the excretory system.
What are the main organs of the excretory system?
Ans. The main organs of the excretory system are kidneys, ureters, urinary bladder and urethra.
Q12. What would happen if digestive system did not work properly?
Ans. If digestive system will not work properly then absorption of nutrients will not occur and the body will be devoid of nutrient and energy.
Q13. What will happen if the waste products remain inside our body?
Ans. It will lead to toxicity and will prove fatal.
Q14. What are called external parts of the body?
Ans. The parts of the body that can be seen are called the external parts of the body.
Q15. What is organ system?
Ans. The group of organs that perform a specific function is called the organ system.
Q16. Describe all types of teeth in the mouth of an adult human.
How many types of teeth are there in humans?
What are the functions of the four types of teeth?
What are the 4 types of teeth and their functions?
Ans. There are four kinds of permanent teeth: Incisors, canines, premolar and molars. In front, there are four flat and thin teeth. These are called the incisors. These help in cutting or biting the food. On each side of the incisors, there is a long, sharp and pointed tooth. These are called the canines. These canines help in tearing the food. Animals that feed on flesh, like lions, tigers etc. have sharp canines. The remaining teeth in the jaw are broad, flat and thick. They are used for grinding the food. There are four premolars and four molars in each jaw.