CBSE Class 7 Science All Chapters MCQs Set A

Question. Name the gas which is used by white blood cells to kill the invading bacteria.
(a) Oxygen
(b) Carbon dioxide
(c) Nitrogen
(d) Chlorine

Answer : A

Question. What is the percentage of oxygen in the inhaled air?
(a) 21%
(b) 16.4%
(c) 18%
(d) 20%

Answer : A

Question. What is the percentage of CO2 in the exhaled air?
(a) 23%
(b) 4.4%
(c) 6%
(d) 0.04%

Answer : B

Question. Normal range of breathing rate per minute in an adult person at rest is
(a) 9 - 12,
(b) 15 - 18,
(c) 21 - 24,
(d) 30 - 33

Answer : B

Question. Muscle cramps occurs due to accumulation of
(a) Lactic acid
(b) Acetic acid
(c) Alcohol
(d) Malice acid

Answer : A

Question. During exhalation the ribs
(a) move down and inwards
(b) move upwards
(c) move outwards
(d) do not move at all

Answer : A

Question. In cockroach, air enters the body through
(a) Lungs
(b) Gills
(c) Spiracles
(d) Skin

Answer : C

Question. The air tubes in insects are called
(a) Bronchus
(b) Tracheae
(c) Nostrils
(d) blowholes

Answer : B

Question. Name the muscular sheet which separates the abdomen from the chest cavity.
(a) Diaphram
(b) Ribs
(c) Spiracles
(d) Tracheae

Answer : A

Question. Birds breathe through
(a) Lungs
(b) Kidney
(c) Spiracles
(d) Skin

Answer : A

Question. Which of the following organism can do anaerobic respiration?
(a) Yeast
(b) Leech
(c) Amoeba,
(d) Fish

Answer : A

Question. The food material used to release energy in body cells, which is considered as a biological fuel is
(a) Glucose
(b) Vitamin
(c) Water
(d) Minerals

Answer : A

Question. Snake breathe through
(a) Lungs
(b) Spiracles
(c) Tracheae
(d) Skin

Answer : A

Question. During anaerobic respiration the end product other than CO2and energy is
(a) O2
(b) Alcohol
(c) Nitrogen
(d) Water

Answer : B

Question. Name the chemical used to test the presence of CO2 in exhaled air.
(a) Lime juice
(b) Lime water
(c) Lime stone
(d) Quick lime

Answer : B

Question. Name the tiny pores present in the leaves of the plants for exchange of gases
(a) Stomata
(b) Tracheae
(c) Chloroplast
(d) Spiracles

Answer : A

Question. Yeast respire an aerobically to produce
(a) Water
(b) Alcohol
(c) Glucose
(d) Lactic acid

Answer : B

Question. The number of times a person breathe in a ______________ is termed as breathing rate
(a) Second
(b) Minute
(c) Hour
(d) Day

Answer : B

Question. Chest cavity is surrounded by
(a) 12 pair of ribs
(b) 10 pair of ribs
(c) 11 pair of ribs
(d) 25 ribs.

Answer : A

Question. Wind pipe is called
(a) Oesophagus
(b) Tracheae
(c) Bronchus
(d) Nasal Cavity

Answer : B

Question. Our _______ cells can respire anaerobically.
(a) nerve
(b) muscle
(c) germ
(d) blood.

Answer : A

Question. Respiration releases energy from the __________.
(a) air
(b) water
(c) food
(d) sunlight.

Answer : C

Question. Glucose breaks down into ___________.
(a) ascorbic acid
(b) citric acid
(c) lactic acid

Answer : C

Question. The accumulation of ______ acid causes muscle cramps.
(a) hydrochloric acid
(b) lactic acid
(c) ascorbic acid
(d) citric acid.

Answer : B

Question. The process of breakdown of food in the cell is called __________.
(a) aerobic respiration
(b) anaerobic respiration
(c) pulmonary respiration
(d) cellular respiration.

Answer : D

Question. Breathing rate is defined as number of times a person breathes in a ___________.
(a) second
(b) minute
(c) hour
(d) day.

Answer : B

Question. When we inhale air, it passes through our nostrils into the ___________.
(a) chest cavity
(b) diaphragm
(c) nasal cavity
(d) cardial cavity

Answer : C

Question. A large muscular sheet which forms the floor of the chest cavity is called
(a) lungs
(b) liver
(c) stomach
(d) diaphragm

Answer : D

Question. Smoking damages
(a) heart
(b) liver
(c) lungs
(d) spleen

Answer : C

Question. A cockroach has small openings on the sides of its body called
(a) trachea
(b) spiracles
(c) setae
(d) none

Answer : B

Question. Though frogs have a pair of lungs they can also breathe through their
(a) nose
(b) heart
(c) liver
(d) skin

Answer : D

Question. Gills help fishes to dissolve ___________ in water
(a) oxygen
(b) carbondioxide
(c) hydrogen
(d) all

Answer : A

Question. Gills are well supplied with___________for gaseous exchange
(a) oxygen
(b) carbondioxide
(c) hydrogen
(d) blood vessels

Answer : D

Question. The root cells also need__________to generate energy
(a) water
(b) sunlight
(c) oxygen
(d) chlorophyll

Answer : C

Question. In insects, the exchange of gases takes place through
(a) spiracles
(b) antennae
(c) trachea
(d) skin

Answer : C

Question. During inhalation, our lungs__________
(a) contracts
(b) exchanges gases
(c) expands
(d) releases energy

Answer : C

Question. Respiration in plants takes place through
(a) root hair
(b) chlorophyll
(c) stomata
(d) buds

Answer : C

Question. Earthworms breathe through their
(a) trachea
(b) spiracles
(c) setae
(d) skin

Answer : D

Question. Lizard and snakes have__________for breathing
(a) heart
(b) lungs
(c) skin
(d) trachea

Answer : B

Question. The percentage of carbondioxide exhaled is
(a) 21 %
(b) 0.04 %
(c) 16.4 %
(d) 4.4 %

Answer : D

Question. Human lungs are covered by two thin membranes called
(a) pleura
(b) diaphragm
(c) thoracic membrane
(d) cartilaginous membrane

Answer : A

Question. In the process of inhalation and exhalation about________of air is breathed in and out
(a) 300 ml
(b) 500 ml
(c) 800 ml
(d) 700 ml

Answer : B

Question. The total area for gas exchange provided by our 300 million alveoli in two lungs is
(a) 63 to 27meters
(b) 36 to 72 meters
(c) 42 to 74 meters
(d) 27 to 47 meters

Answer : B

Question. Mussels respire through their
(a) skin
(b) gills
(c) lungs
(d) trachea

Answer : B

Question. The voice box is called
(a) epiglottis
(b) glottis
(c) larynx
(d) vocal cords

Answer : C

Question. Radiation
(a) does not require any medium
(b) is the process of transfer of heat in liquids
(c) is the process of transfer of heat in which heat traveles in one direction.
(d) Occurs in solids.

Answer : A

Question. A Thermos flask prevents loss or gain of heat by
(a) conductions only
(b) convections only
(c) radiation only
(d) all the above

Answer : D

Question. Handles of cooking utensils should be made of material that
(a) conducts heat well
(b) does not conduct heat
(c) radiate heat well
(d) does not radiate heat

Answer : B

Question. Sea breeze and land breeze
(a) are caused by currents set up in air due to conduction
(b) are caused by currents set up in air due to convection
(c) are caused by currents set up in air due to radiation
(d) have no relation to conduction, convection and radiation

Answer : B

Question. Which of the following is the best heat insulator
(a) air
(b) steel
(c) copper
(d) iron

Answer : A

Question. Heat from the sun reaches us by the process of
(a) conduction
(b) convection
(c) radiation
(d) all the above

Answer : C

Question. In liquids heat is transferred
(a) only by convection
(b) only by radiation
(c) mainly by conduction and convection
(d) none of these

Answer : A

Question. Stainless steel pans are provided with copper bottom because
(a) copper is easier to clean than stainless steel
(b) such pans are colourful
(c) copper bottom makes the pan more durable
(d) copper is better conductor of heat than stainless steel

Answer : D

Question. A polished silvery surface is
(a) good absorber of heat
(b) good reflector of heat
(c) poor reflector of heat
(d) None of these

Answer : B

Question. Land breeze blows in coastal regions during
(a) day
(b) summer
(c) winter
(d) night

Answer : D

Question. A wooden spoon is dipped in a cup of icecream. Its other end
(a) does not become cold
(b) becomes cold by the process of radiation
(c) becomes cold by the process of convection
(d) becomes cold by the process of conduction

Answer : A

Question. Dark coloured clothes are preferred during
 a) summer
(b) sand storm
(c) winter
(d) none of these

Answer : C

Question. A black body with rough surface is a
(a) good reflector and poor absorber of heat
(b) good absorber and good radiator of heat
(c) good absorber and poor radiator of heat
(d) good reflector and poor radiator of heat

Answer : B

Question. Range of laboratory thermometer is generally from
(a) -10° F to 110° F
(b) 10° C to 110° C
(c) 10° C to -110° C
(d) -10° C to 110° C

Answer : D

Question. Normal temperature of human body is
(a) 37° F
(b) 37° C
(c) 39° C
(d) 39° F

Answer : B

Question. Which of the following is a good conductor of heat
(a) Wool
(b) Water
(c) Wood
(d) Silver

Answer : D

Question. Device used for measuring temperature
(a) Barometer
(b) Odometer
(c) Thermometer
(d) Speedometer

Answer : C

Question. Transmission of heat energy with actual movement of particles
(a) Conduction
(b) Convection
(c) Radiation
(d) None of these.

Answer : B

Question. When two bodies are kept in contact heat flows from
(a) a body at higher temperature to the body at lower temperature
(b) a body at lower temperature to the body at higher temperature
(c)no flow of heat
(d) all of the above

Answer : A

Question. A cold steel spoon dipped in a cup of hot milk. It transfers heat to the other end by the process of
(a) radiation
(b) convection
(c) conduction
(d) none of these

Answer : A

Question. The word acid comes from the Latin word ‘ acere ‘ which means
(a) Sweet
(b) Salty
(c) Neutral
(d) Sour

Answer : D

Question. Substances which are bitter in taste, feel soapy on touching are known as
(a) Acids
(b) Bases
(c) Indicators
(d) Neutral solution

Answer : B

Question. Special type of substances used to test whether a substance is acidic/basic are known as
(a) Indicators
(b) Acids
(c) Bases
(d) Salt

Answer : A

Question. Some naturally occurring indicators are
(a) Turmeric
(b) Litmus
(c) China rose
(d) All the above

Answer : D

Question.The most commonly used natural indicator’ Litmus’ is extracted from
(a) Lichens
(b) Turmeric
(c) Indicators
(d) China rose

Answer : A

Question. Litmus is available in the form of
(a) Litmus paper
(b) Lichens
(c) Indicator
(d) China rose

Answer : A

Question. Neutral solutions which do not change the colour of either red/blue litmus are known as
(a) Neutral solutions
(b) Acid solutions
(c) Basic solutions
(d) Neither acidic nor basic

Answer : A

Question. Acetic acid is found in
(a) Curd
(b) Spinach
(c) Citrus fruits
(d) Vinegar

Answer : D

Question. Formic acid is found in
(a) Curd
(b) Spinach
(c) Ant’s sting
(d) Ascorbic acid

Answer : C

Question. Citric acid is found in
(a) Curd
(b) Citrus fruits
(c) Ascorbic acid
(d) Lime water

Answer : B

Question. Lactic acid is found in
(a) Curd
(b) Citrus fruits
(c) Gooseberry
(d) Lime

Answer : A

Question. Oxalic acid is found in
(a) Spinach
(b) Curd
(c) Oranges
(d) Unripe mangoes

Answer : A

Question. Ascorbic acid is found in
(a) Amla & Citrus fruits
(b) Curd
(c) Oranges & lemon
(d) Unripe mangoes

Answer : A

Question. Tartaric acid is found in
(a) Tamarind
(b) Grapes
(c) unripe mangoes
(d) All of the above

Answer : D

Question. Calcium hydroxide is found in
(a) Calcium carbonate
(b) Calcium chloride
(c) Calcium
(d) Lime water

Answer : D

Question. Ammonium hydroxide is found
(a) Window cleaner
(b) Detergents
(c) Soap
(d) Milk of magnesia

Answer : A

Question. Sodium hydroxide is found in
(a) Soap
(b) Window cleaner
(c) Calcium hydroxide
(d) Sodium

Answer : A

Question. Potassium hydroxide is found in
(a) Soap
(b) Window cleaner
(c) Potassium
(d) Potassium chlorate

Answer : A

Question. Magnesium hydroxide is found in
(a) Milk of magnesia
(b) Magnesium chloride
(c) Magnesium ribbon
(d) Magnesium hydroxide

Answer : A

Question. Who is the 18 year old Harijan youth in Mulk Raj Anand’s ‘Untouchable’
(a) Arnold
(b) Bakha
(c) Swami

Answer : B

Question. Name the hero of John Bunyan’s ‘Pilgrims Progress’
(a) God
(b) Satan
(c) Christian

Answer : C

Question. Identify the young boy who became well known because of an old lamp he held?
(a) Pinocchio
(b) Hansel
(c) Aladdin

Answer : C

Question. Name the wooden boy whose nose grew when he lied?
(a) Pinocchio
(b) Hansel
(c) Aladdin

Answer : A

Question. Find out the character who was a giant in one city and a dwarf in another?
(a) Frankenstein
(b) Gulliver
(c) Sherlock Holmes

Answer : B

Question. Identify the writer who created the famous character Mowgli?
(a) Rudyard Kipling
(b) Robert Grave
(c) R. L. Stevenson

Answer : A