1. Define a cell.
ANS: A cell is the smallest
structural and functional unit of a living organism.
2. How tissues are formed?
ANS: A group of cells organised to
perform a common function, make tissues.
3. Tissues collectively form
______.
ANS: organs
4. How one organ system is
formed?
ANS: The different organs, in turn,
working together for a certain major activity, form an organ system.
5. Name the different organ
system of human body.
ANS: The different organ system of
human body are,
i) digestive system
ii) excretory system
iii) respiratory system
iv) skeletal system
v) circulatory (transport) system
vi) reproductive system
vii) nervous system
6. Define digestion.
ANS: The process of breaking down of
complex food materials into simple and soluble particles, is called digestion.
7.
Define ‘digestive system’.
ANS: The system which is responsible
for digestion, is called the digestive system.
8. Name the organs that make up the
digestive system.
ANS: The human digestive system consists of mouth, food pipe, stomach, small
intestine, large intestine, some glands and anus.
9.
Name the first part of the digestive system.
ANS: Mouth is the first part of the digestive
system.
10. What is oral cavity?
ANS: The mouth is also known as the
oral cavity.
11. Name the organ where the
process of digestion begins.
ANS: The process of digestion begins
in the mouth.
12.
Name the organ through which food enters the body.
ANS: Food enters through our mouth.
13.
Name the organs present inside our mouth.
ANS: Teeth, tongue and salivary
glands are present inside our mouth.
14.
How do our teeth help us?
ANS: i) Teeth help to bite and chew
the food.
ii) They also give shape to our face
and help us to speak clearly.
15.
Name the two sets of teeth that are formed during one’s life time.
ANS: The two sets of teeth are,
temporary teeth (milk teeth) and permanent teeth.
16.
When do the teeth begin to appear in a human baby?
ANS: When the baby is about six
months old, his/her teeth begin to appear.
17.
The number of milk teeth (temporary teeth) in humans is ______
ANS: 20
18.
When do the temporary teeth (milk teeth) start to fall out?
ANS: Between the age of six and
twelve years, the milk teeth fall out one by one.
19.
What are permanent teeth?
ANS: The set of teeth which replace
the milk teeth, are the permanent teeth.
20.
What is the number of permanent teeth?
ANS: The number of permanent teeth in
humans, is 32.
21.
Name the different types of teeth.
ANS: The different types of teeth
are,
i) Flat teeth (Incisors)
ii) Pointed teeth (Canines)
iii) Broad and Grooved teeth
(Premolars and molars)
22.
Where the flat teeth are located?
ANS: Flat teeth, are located in the
front of the mouth.
23.
What is the shape of incisors?
ANS: Incisors are flat in shape.
24.
What is the total number of incisors (flat teeth) in our mouth?
ANS:
Total 8 incisors are present in our mouth.
25.
How many incisors are present in each jaw?
ANS: 4 incisors are present in each
jaw.
26.
What is the function flat teeth (incisors)?
ANS: The incisors are used for biting
and cutting the food.
27.
Where the pointed teeth are located?
ANS: The pointed teeth are located on
either side of flat teeth.
28.
What is the shape of canines?
ANS: Canines are pointed in shape.
29.
What is the number of canines in each jaw of human mouth?
ANS: 2 canines are present in each
jaw of human mouth.
30.
What is the total number of canines in human mouth?
ANS: 4 canines are present in human
mouth.
31.
What is the function of canines?
ANS: Canines are used for tearing the
food.
32.
What is the shape of pre-molars and molars?
ANS: Pre-molars and molars are broad
and grooved.
33.
Where are the pre-molars located?
ANS: Pre-molars are located next to
canines.
34.
What is number of pre-molars in each jaw?
ANS: 4 pre-molars are present in each
jaw.
35.
What is the total number of pre-molars in humans?
ANS: The total number of premolars in
human mouth is 8.
36.
Where are molars located?
ANS: Molars are located next to
premolars.
37.
What is the number of molars in each jaw?
ANS: The number of molars in each jaw
of human being is 6.
38.
What is the total number of molars in human mouth?
ANS: The total number of molars in
human mouth is 12.
39.
What is the function of molars and premolars?
ANS: molars and pre-molars are used
for chewing and grinding the food.
40.
Name the different types of teeth present in the mouth. Also mention
their numbers, location and functions.
ANS:
Type of teeth |
Shape |
Location |
Number in Each Jaw |
Total number in Human
Mouth |
Function |
Incisors |
Flat |
In the front |
4 |
8 |
Biting and cutting the food. |
Canines |
Pointed |
On either side of incisors |
2 |
4 |
Tearing the food |
Premolars |
Broad and Grooved |
Next to canines |
4 |
8 |
Chewing and grinding the food |
Molars |
Broad and Grooved |
Next to premolars |
6 |
12 |
Chewing and grinding the food. |
41. Name the two parts of a
tooth.
ANS: The two parts of a tooth are,
the crown and the root.
42. Define crown of a tooth.
ANS: The crown is the visible part of
the tooth.
43. Define root of a tooth.
ANS: The part of the tooth which lies
inside the gums and is attached to a socket in the jawbone, is called as the
root.
44. The outer white part of the
tooth is made of _____.
ANS: enamel
45. Name the hardest substance
in the human body.
ANS: enamel
46.
What is the function of tongue?
ANS: i) Tongue is used for tasting,
licking and speaking.
ii) Tongue also pushes the food into
the food pipe at the time of swallowing.
47.
Name the sensitive sites of tongue and their location.
ANS: i) The back of the tongue is
sensitive to bitter taste.
ii)
Its sides are sensitive to sour and salty tastes.
iii) The tip of the tongue is sensitive
to sweet taste.
48.
Name the glands present in the mouth.
ANS: Salivary glands are present in
the mouth.
49.
How many pairs of salivary glands present in the mouth?
ANS: There are three pairs of
salivary glands present in the mouth.
50.
Name the gland that secretes saliva.
ANS: The salivary glands secrete
saliva.
51.
What is the function of saliva?
ANS: (i) The saliva helps to moisten
and soften the food so that it can be easily swallowed.
(ii) Enzymes present in saliva helps
in the digestion of carbohydrates also.
52.
How the process of digestion is carried out in mouth?
ANS: i) Teeth helps in breaking the
food into smaller pieces and chewing it.
ii) Saliva gets mixed with the food
and makes it soft.
iii) Saliva converts insoluble starch
into soluble sugar.
53.
Why is it important to chew the food properly?
ANS: It is important to chew the food
properly for proper digestion of food.
54.
The food from
the mouth goes into the _____.
ANS: Food pipe
55. The food pipe is a ____
organ.
ANS: muscular
56. The other name of food pipe
is ______.
ANS: Oesophagus
57. The food pipe is about
_____ in length.
ANS: 30 cm
58. The food from the food pipe goes into the _______.
ANS: Stomach
59. How the food passes
downwards in the food pipe?
ANS: The contraction of the muscles
present in the food pipe is responsible for pushing the food downwards.
60. Name the gland present in
the stomach.
ANS: Gastric glands are present in
the stomach.
61. Name the digestive juice
secreted in the stomach.
ANS: Gastric juice
62. The food generally stays in
the stomach for about ____ hours.
ANS: 2-3 hours
63. What happens to the food
when it enters the stomach?
ANS: i) The food mixes with the
digestive juices secreted by the walls of the stomach.
ii) The food is churned and changed
into a paste-like substance.
iii) Thus, the food gets partially
digested here.
64.
The food leaves the stomach and enters into the ______.
ANS: Small intestine
65.
Name two associate glands that pour their juices into the small
intestine.
ANS: Liver and pancreas pour their
juices into the small intestine.
66.
Name the largest gland of our body.
ANS: Liver is the largest gland of
our body.
67. The liver is ____ in
colour.
ANS: dark brown
68. Liver secretes ____ juice.
ANS: bile juice
69. The bile juice is ______ in
colour.
ANS: brownish-green
70. The pancreas secretes _____
juice.
ANS: pancreatic juice
71. Name the longest part of
the digestive system.
ANS: small intestine
72. Name the part of the
digestive system which is highly coiled.
ANS: small intestine
73.
What happens to the food when it enters the small intestine?
ANS: i) Juices from liver and
pancreas, mixes with the food in the small intestine.
ii) The food gets completely
digested.
iii) The walls of the small intestine
absorb the digested food and pass it to blood.
74.
How the digested food reaches all parts of the body?
ANS: Blood carries the digested food
from the small intestine to all parts of the body.
75. The small intestine is
nearly _____ cm in diameter and ____ m in length.
ANS: 3 cm in diameter and 7 m in
length.
76. The large intestine is
nearly _____ cm in diameter and _____ m in length.
ANS: 7 cm in diameter and 1.5 m in
length
77. The small intestine is
longer than the large intestine. So why is it called as small?
ANS: The small intestine is longer
than the large intestine. But the names are given according to the diameter.
Diameter of large intestine is about 7 cm which is greater than the diameter of
small intestine which is only about 3 cm.
78.
What happens to the undigested food?
ANS: i) The undigested food passes
into the large intestine.
ii) Then it is collected in the
rectum and is eliminated through the anus.
79.
Which part of the digestive system absorbs water?
ANS: Large intestine absorbs water.
80. Name the external opening
of the alimentary canal.
ANS: Anus
81.
What is breathing?
ANS:
The process of taking in oxygen and giving out carbon dioxide is called
breathing.
82. Name the organs
present in human breathing system.
ANS:
Nasal cavity, pharynx, wind pipe, lungs and diaphragm are the parts of the
human breathing system.
83. Define respiration.
ANS: Respiration is the process of
breaking down of food with the help of oxygen which is taken in to release
energy. Carbon dioxide is also released in this process as a waste product.
84. Air enters the nose through
the _____.
ANS: Nasal Cavity
85. What happens to the air
when it passes through the nasal cavity?
ANS: When air passes through the
nasal cavity, it gets warmed up and also gets filtered.
86. Why are the hairs present
in the nostrils important?
ANS: The hair, present in the
nostrils, stop the dust and germs, from entering the respiratory system.
87. Air from the nasal cavity
passes into ______.
ANS: pharynx
88. Air from the pharynx,
passes into a chamber called the ______.
ANS: larynx
89. Which part of the
respiratory system is called as the voice box?
ANS: larynx
90. _______ guards the opening
between pharynx and larynx.
ANS: epiglottis
91. What is the function of
epiglottis?
ANS:
Epiglottis guards the opening between pharynx and larynx. Epiglottis
keeps it open during breathing but closes the opening while swallowing.
92. The wind pipe is situated
in the _____ of the food pipe.
ANS: front
93. The wind pipe is
approximately _______ cm in length.
ANS: 12 cm
94. The wind pipe is
approximately _____ cm in diameter.
ANS: 2.5 cm
95. As the wind pipe enters the
lungs, it gets divided into ______.
ANS: bronchi
96. Lungs are situated on either
side of the ______.
ANS: chest cavity
97. Describe the
process of breathing in lungs?
ANS:
i) We inhale air through the nasal openings of the nose.
ii)
From the nose, air goes to the lungs through the wind pipe.
iii)
In the lungs, oxygen is taken up by the blood and carbon dioxide is unloaded.
iv)
This carbon dioxide along with water vapour is then exhaled through the nose.
98. _______ gas is
consumed in the process of breathing.
ANS:
Oxygen
99. ________ gas is
driven out of the body as a waste product, in the process of breathing.
ANS:
Carbon dioxide
100. How physical
exercises help us?
ANS: Physical exercises, like running, walking and
playing, help to keep our body and breathing system healthy.
101. How does the diaphragm
enable the lungs to move?
(or) How does the diaphragm help in the
process of breathing?
ANS: The diaphragm moves down during
inhalation and moves up during exhalation. This helps in the expansion and
contraction of the lungs. Thus, breathing takes place.
102. A human baby has a _____
coloured lungs.
ANS: pink
103. Why the lungs get darkened
as a child grows older?
ANS: The lungs get darkened as a
child grows older due to the presence of impurities in the air.
104. The lungs of an adult man
can hold about ____ litres of air on an average.
ANS: 6 litres
105. During sneezing, air
rushes out at about ______ km/hr.
ANS: 160 km/hr
106. Name the parts of the
human circulatory system.
ANS: The parts of the human
circulatory system are, heart, blood vessels and blood.
107. Where is the heart located
in human beings?
ANS: The heart is located, slightly
towards the left, in the chest.
108. How many chambers are
there in human heart?
ANS: 4
109. Name the upper two
chambers of the heart.
ANS: right auricle and left auricle
110. Name the lower two
chambers of the heart.
ANS: right ventricle and left ventricle
111. Name all the four chambers
of the human heart.
ANS: The four chambers of the human
heart are, right auricle, right ventricle, left auricle and left ventricle.
112. Name the chambers which
contain oxygen rich blood.
ANS: The left auricle and left
ventricle contain oxygen rich blood.
113. Name the chambers which
contain blood rich in carbon dioxide.
ANS: The right auricle and right
ventricle contain blood rich in carbon dioxide.
114. What is the main function
of the heart?
ANS: The main function of the heart
is to pump blood and keep it moving in the blood vessels.
115. Which side of the heart is
bigger?
ANS: The left side of the heart is
bigger than the right side of the heart.
116. The sound that the heart
makes when the valves open and close is called as ____.
ANS: heart beat
117. heart beat can be heard by
using a device called as _____.
ANS: stethoscope
118. Why doctors use
stethoscope?
ANS: Doctors use a stethoscope to
know the heart beat rate.
119. On an average, the heart
beats ____ times per minute.
ANS: 72 times
120. The heart beats ____ times
per minute in a new born baby.
ANS: approximately 140 times
121. The heart beats _____
times per minute in a three year old child.
ANS: approximately 100 times
122. Blood moves in our body
through the ______.
ANS: blood vessels
123. What are the types of
blood vessels?
ANS: The three types of blood vessels
are- arteries, veins and capillaries.
124. Name the blood vessel
which carry oxygen rich blood.
ANS: Artery
125. Name the blood vessel
which carry blood rich in carbon dioxide.
ANS: vein
126. What are arteries?
ANS: The blood vessels, which take
blood away from the heart, to various parts of the body, are called arteries.
127. What are veins?
ANS: The blood vessels, bringing
blood back to the heart, from different parts of the body are called veins.
128. What are capillaries?
ANS: The fine vessels which connect
arteries to veins, are called as capillaries.
129. What are components of
blood?
ANS: The components of blood are, Red
Blood Cells (RBCS), White Blood Cells (WBCs) and blood platelets.
130. What are the functions of
blood?
ANS: The functions of the blood are
to:
i) transport oxygen, food materials
and hormones to all parts of the body.
ii) take back carbon dioxide, from
all parts of the body, to the lungs.
iii) protect the body from diseases
and other infections.
iv) help to maintain the body at a
constant temperature.
131. Why the colour of blood is
red?
ANS: Blood is red in colour due to
the presence of haemoglobin in it.
132. Name the mineral present
in haemoglobin.
ANS: Iron