Class 7 Respiration In Organisms Complete+Extra Notes

Class 7 Respiration In Organisms Complete+Extra Notes is important for the students of 7th standard. Notes are provided here in such a way that students can understand the Chapter in an interesting way. This Class 7 Respiration In Organisms Complete+Extra Notes could provide extra benefits in excelling a students curriculum . Students should practice their solutions regularly to prepare effectively for their examination.

Class 7 Respiration In Organisms Complete+Extra Notes are outlined for students to easily understand the concepts. Hope students would be benefited .

Tick the correct option

1. Where does gaseous exchange take place in an earthworm ?

a. moist skin

b. lungs

c. gills

d. body surface

Ans : a. moist skin

2. What is utilized during respiration to release energy ?

a. protein

b. lactic acid

c. glucose

d. cellulose

Ans : c. glucose

3. In which type of habitat do animals that respire through gills live ?

a. aquatic

b. grasslands

c. terrestrial

d. desert

Ans : a. aquatic

4. Which gas is released when human beings respire ?

a. oxygen

b. hydrogen

c. ozone

d. carbon dioxide

Ans : d. carbon dioxide

5. What is not required for anaerobic respiration ?

a. energy

b. glucose

c. oxygen

d. carbon dioxide

Ans : c. oxygen

6. Where does gaseous exchange take place in butterflies ?

a. stomata

b. spiracles

c. air sacs

d. feelers

Ans : b. spiracles

7. What transports oxygen to every part of the body ?

a. blood

b. lungs

c. water

d. trachea

Ans : a. blood

8. What waste products are released in aerobic respiration ?

a. carbon dioxide and alcohol

b. carbon dioxide and water

c. carbon dioxide and oxygen

d. carbon dioxide and nitrogen

Ans : b. carbon dioxide and water

Fill in the blanks

1. The trachea is commonly called the windpipe .

2. In most vertebrates , gaseous exchange occurs through lungs .

3. Fish respire through gills .

4. The air in the alveoli is called alveolar air .

5. During inhalation , the diaphragm contracts .

6. Below the rib cage , there is a sheet of muscles called the diaphragm .

Answer the following questions in one sentence

1. What is breathing ?

Ans : Breathing is a continuous process in which we breathe in and breathe out air from our body .

2. What is breathing rate ?

Ans : The number of times a person breathes in a minute is called the breathing rate .

3. How are dust particles prevented from entering the lungs ?

Ans : The hair and mucus present in the nostrils trap dust and germs present in air thus preventing dust particles from entering our lungs .

4. What is respiration without oxygen called ?

Ans : The type of respiration which occurs without oxygen is termed as anaerobic respiration.

5. How do microorganisms respire ?

Ans : In microorganisms like amoeba , the respiration takes place through their moist body surface .

6. What is produced when human cells respire aerobically ?

Ans : When human cells respire aerobically carbon dioxide , water and energy are produced .

7. How do plants take in air ?

Ans : Plants take in air from the atmosphere through stomata .

8. Where does gaseous exchange occur in fish ?

Ans : Gaseous exchange occurs when water flows over the gills .

Answer the following questions in two sentences

1. Describe gaseous exchange in the human body ?

Ans : When we breathe in , fresh air fills the alveoli of the lungs as a result of which oxygen passes into the blood in the capillaries and binds to the red blood cells . At the same time , carbon dioxide passes out of the blood into the alveoli , and this entire process is called gaseous exchange .

2. What is cellular respiration ?

Ans : The process of breaking down of food in the cells with the release of energy is called cellular respiration , and it occurs in every cell of an organism .They are of two types : a) Aerobic respiration & b) Anaerobic respiration .

3. Differentiate between aerobic and anaerobic respiration .

Ans :

4. Explain respiration in birds .

Ans : Birds have lungs with air sacs through which they respire . The air sacs make the body of the bird light in weight ,and thus is considered as an adaptation that helps birds fly .

5. How does gaseous exchange take place in earthworms ?

Ans : Earthworms with a soft body living in moist soil exchange gases through their moist skin . Their entire body surface is the respiratory organ .

6. What causes cramps in a person ?

Ans : When we overexert (overwork ) our muscles while playing games such as football,hockey etc ,our muscles fail to receive enough oxygen and begins to respire anaerobically for a short time . This produces lactic acid and the person develops cramps temporarily .

Answer the questions in about 4-5 sentences.

1. How are respiratory systems different in different animals ?

Ans : Respiratory system varies from animal to animal. In microorganisms like amoeba , respiration occurs through moist body surface . Soft body organisms like earthworms also respire through moist skin . Frogs when present in water respire through moist skin and when on land with help of their lungs , but frogs also breathe in air from the atmosphere even when present in water . Similarly,animals such as sea snakes , sea turtles have lungs and breathe in air directly from the atmosphere . Aquatic animals such as fish , lobsters, crabs respire through their gills .

2. Differentiate between inhalation and exhalation .

Ans :

3. How does the air that we breathe in reach the lungs ?

Ans : When we inhale air, it passes through our nostrils into the nasal cavity. From the nasal cavity, the air reaches our lungs through the windpipe ( trachea) . The trachea divides at the lower end into 2 narrower tubes called bronchi , which further divides into numerous extremely narrow tubes in each lung . These tubes open into tiny air sacs called alveoli .

4. How is carbon dioxide removed from the body ?

Ans : As the blood flows through the body , CO2 formed during respiration passes through the blood and binds to the red blood cells . This blood reaches the heart which then sends the blood to the lungs . In lungs , CO2 detaches from the red blood cells and enters the air sacs . Then CO2 is removed from the lungs when we breathe out .

5. Explain respiration in insects .

Ans : The respiratory system in insects is called Tracheal System and is made up of spiracles and trachea . An insect thus takes air through tiny holes called spiracles which are located on their body ,these spiracles then open into narrow tubes called trachea ,which form a network in their entire body, through which air is supplied to every part of the body . Air sacs are found attached to the tracheal system .

Extra – Questions

1. What are the similarities between Aerobic and Anaerobic respiration ?

Ans :

2 . What is the  normal range of breathing rate per minute in an average adult person at rest ?

Ans : The  normal range of breathing rate per minute in an average adult person at rest is 14 – 16 .

3 . Define blood capillaries .

Ans : These are extremely narrow blood vessels with extremely thin walls .

4. Why is breathing called an involuntary action ?

Ans : Breathing is called an involuntary action as it is controlled by the brain.

5 . How does the diaphragm help in breathing ?

Ans : The diaphragm helps move air in and out of the lungs. During inhalation, the diaphragm contracts, increasing the volume of the lungs, lowering the pressure in the lungs below atmospheric pressure, and allowing air to flow into the lungs. When we exhale, the diaphragm relaxes and the volume of the lungs decreases, causing the pressure in the lungs to rise slightly above atmospheric pressure. This expels air from the lungs.

6 . Which two gases are exchanged during respiration by the human body ?

Ans : Carbon dioxide & Oxygen are the two gases exchanged during respiration by the human body .

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