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Ncert Exemplar Solutions Class 7 Science Respiration in Organisms
Welcome to NCTB Solutions. Here with this post we are going to help 7th class students for the Solutions of NCERT Exemplar Class 7 Science Book, Unit 10, Respiration in Organisms. Here students can easily find step by step solutions of all the problems for Respiration in Organisms, Also here our Science teacher’s are solved all the questions with easily understandable language with proper guidance so that all the students can understand easily.
Respiration in Organisms all Question Solutions :
Multiple Choice Questions :
Question no – (1)
Sometimes when we do heavy exercise, anaerobic respiration takes place in our muscle cells. What is produced during this process?
Answer :
The correct answer is option – (d)
Lactic acid will produced during this process.
Question no – (2)
Yeast is used in wine and beer industries because it respires
Answer :
The appropriate answer is option – (c)
Yeast is used in wine and beer industries because it respires anaerobically producing alcohol.
Question no – (3)
During the process of exhalation, the ribs move
Answer :
The answer is option – (a)
During the process of exhalation, the ribs move down and inwards.
Question no – (4)
Breathing is a process that
Answer :
The answer is alternative – (c) (i) and (iii)
Breathing is a process that provides O2 to the body and helps the body to get rid of CO2.
Question no – (5)
Fish breathe with the help of gills which are richly supplied with blood vessels. The gills help the fish to
Answer :
The correct option is – (b)
The gills help the fish to take in oxygen dissolved in water.
Question no – (6)
Earthworms and frogs breathe through their skin because of which the skin of both the organisms is
Answer :
The correct option is – (d)
Earthworms and frogs breathe through their skin because of which the skin of both the organisms is moist and slimy.
Very Short Answer Questions :
Question no – (7)
Answer :
(a) Oxygen breaks down glucose outside the cells of organisms
This statement is False.
Reason : Oxygen breakdown glucose inside the cell of organisms.
(b) Frogs can breathe through their skin as well as lungs
This statement is True.
(c) Insects have spiracles on the lower surface of the body
This statement is False.
Reason : Insects have spiracles on the side of their body.
(d) Exhaled air has more percentage of CO2 than inhaled air
This statement is True.
Question no – (8)
Answer :
(a) The roots of a plant take up oxygen from the Air trapped between the Soil particles.
(b) Diaphragm forms the floor of the chest cavity.
(c) Exchange of gases in the leaves take place with the help of Stomata
(d) Cockroaches breathe with the help of air tubes called Trachea.
Short Answer Questions :
Question no – (9)
Answer :
(a) cockroach, grasshopper, snail, ant
Snails : – Apart from snails all others are insects which breathe through a network of air tube called trachea but a snail doesn’t have trachea.
(b) lizard, cow, earthworm, snake
Earthworm : – Apart from earthworms all other are animals that respire with the help of lungs while earthworms respire through their moist skin.
(c) crocodile, whale, dolphin, fish
Fish : – Apart from fish all others respire with the help of organ called as lungs while fish respire with the help of gills.
(d) snake, tadpole, crow, goat
Tadpole : – Apart from tadpole all others have lungs which help them to breathe while tadpoles has gills which help them to respire.
Question no – (10)
Answer :
Oxygen gas present in air is essential for aerobic respiration.
When we breathe in air the oxygen in it helps to break down food into water and carbon dioxide. This breakdown of food releases energy which is essential for the body to work.
Question no – (11)
Answer :
The correct order should be sleeping, watching t.v, brisk walk, cycling.
The activities are placed in the following order because the more physically challenging work we do, the more oxygen our body needs in order to gain energy for completing those activities.
Question no – (12)
Answer :
The air we breathe out is always warm so when Boojho and Paheli were talking to each other the warm air they breathe out quickly condensed into mist because of the cold surrounding air in the atmosphere. This resulted in their breath to look like smoke.
Question no – (13)
Answer :
When we feel drowsy or sleepy our body lacks oxygen so it is a natural instinct of human to open their mouth and yawn. It allows us to breathe in large amount of oxygen in our body.
Question no – (14)
Answer :
Insects breathe with the help of pores called spiracles while plants breathe with the help of pores called stomata. So difference between spiracles and stomata on the basis of their position, number and extension are –
• Spiracles are present at the side of insects body while stomata are present at the • lower side of leaves
• Stomata are very high in numbers while spiracles are present in small numbers
• Stomata does not lead to any respiratory networks while spiracles lead to a network of tubes called trachea.
Long Answer Questions :
Question no – (15)
Answer :
(a) What can be the possible reasons for the pain in her legs?
Often when we do strenuous works our body does not get enough oxygen to produce energy so our body starts to respire anaerobically. During this process the glucose is partially broken and lactic acid is produced. It’s accumulation in the muscles causes pain.
(b) Why did she feel comfortable after a massage?
She felt comfortable after a massage because it improves the circulation of blood which brings more oxygen to the cramped muscles where the lactic acid is broken into carbon dioxide and water.
Question no – (16)
Answer :
(a) In which jar, will the amount of CO2 be the highest and why?
The jar ‘C’ will have the highest amount of carbon dioxide as the mice jar is filled with the exhales of the mice and since there is no plant in the jar the carbon dioxide released can’t be used by plant.
(b) In which jar, will the amount of CO2 be the lowest and why?
The jar ‘A’ will have the lowest amount of carbon dioxide because the carbon dioxide released by the plant during respiration will be used by the plant itself for photosynthesis.
Question no – (17)
Answer :
(a) Which process is being tested in the activity?
= It is tested whether Carbon dioxide is released in the exhalation or not.
(b) What is the result of the activity? give reasons
The test tube A will remain unchanged but the lime water in test tube B will turn milky because carbon dioxide reacts with lime water to turn it milky but it does not react with water.
Question no – (18)
Answer :
(a) Why did the dough rise?
The yeast in the dough starts to respire anaerobically which releases carbon dioxide. This carbon dioxide fills up the dough and make it rise.
(b) Why did the dough smell sour?
The anaerobic respiration of yeast produces ethyl alcohol which results in sour smell of the dough.
(c) Why was sugar added to the dough?
The sugar was added in the dough because it acts as food for then yeast.
(d) What would have happened if the dough was kept in the refrigerator, soon after it was prepared?
If the dough was kept in the refrigerator the yeast would have not reproduced or repaired thus the dough would not rise or have a sour smell which is a necessity for a good dough.
Question no – (19)
Answer :
The figure A represents inhalation and figure B represents exhalation.
Question no – (20)
Answer :
(a) → (iii) Spiracles.
(b) → (iv) Skin.
(c) → (i) Lungs.
(d) → (ii) Gills.
Other Chapter Solutions :
👉 Heat
👉 Physical and Chemical Changes
👉 Weather, Climate and Adaptation of Animals to Climate
👉 Soil
👉 Transportation in Animals and Plants
👉 Electric Current and Its Effects
👉 Light
👉 Wastewater Story
