Biology class 10thClass Matric Part 2 Notes

10th class biology chapter 10 Gaseous Exchange

10th class biology chapter 10 Gaseous Exchange on by Bilal Article

Shorts and Simple Question & Answers

Q1.Differentiate between breathing and cellular respiration?
Ans. Breathing
(i) Breathing is used for the process through which animals take air in bodies to get oxygen from it and then give out the air for getting rid of carbon dioxide.
(ii) It is only the mechanical or physical process for exchange of gases.
Cellular respiration (Board 2013)
(i) Cellular respiration is the process in which the C-H bonds in food are broken by oxidation reduction reactions and the energy is transformed into ATP.
(ii) It is a mechanical and biochemical process.

Q2. Trace the path of air from the nasal cavity to the alveoli?
Ans.The following is the path of air:
Nasal cavity
alveolar ducts

Q3. How will you differentiate between stomata and lenticels?
Ans. Stomata
(i) The leaves and young stems have stomata in their epidermis.
(ii) The gaseous exchange occurs through these stomata.
(i) In woody stems and mature roots, there are certain pores in the layer of bark.
(ii) The lenticels allow air to pass through them.

Q4. What are alveolar ducts?
Ans. In the lungs, the bronchioles end as fine tubules called the alveolar ducts.

Q5. Define Alveolus?
Ans. Within the lungs, each alveolar duct opens into a cluster of pouches called alveoli. The alveoli form the respiratory surface in humans.

Q6. What is Asthma? Write its symptoms?
Ans. Asthma is a form of allergy, in which there is inflammation of the bronchi, more mucous production and narrowing of the airways. In asthma patients the bronchi and bronchioles become sensitive to different allergens and patient feels difficulty in breathing. The major symptoms are:
(i) Shortness of breath
(ii) Wheezing
(iii) Cough and chest tightness

Q7. Define breathing?
Ans. The term breathing is used for the process through which animals take air in bodies to get oxygen from it and then give out the air for getting rid of carbon dioxide. It is only the mechanical or physical process for exchange of gases.

Q8. What are bronchioles?
Ans. The bronchi continue dividing in the lungs until they make several fine tubes called bronchioles. The bronchioles progressively lose the cartilages as they become narrower.

Q9. What is bronchitis?
Ans. Bronchitis is an inflammation of the bronchi or bronchioles. It results in excessive secretion of mucous into the tubes leading to the swelling of tubular walls and narrowing of tubes. It is caused by viruses, bacteria or exposure to chemical irritants e.g. tobacco smoke.

Q10. Define bronchus?
Ans. On entering the chest cavity, the trachea divides into two smaller tubes called bronchus. The bronchi also have cartilagenous plates in their walls.

Q11. Define diaphragm?
A thick muscular structure is present below the lungs is called diaphragm.

Q12. What is emphysema?
Ans. Emphysema is the destruction of the wall of the alveoli. It results in larger sacs but with less surface area for gaseous exchange. As lung tissue breaks down, the lungs do not come back to their original shape after exhalation. So air cannot be pushed out and is trapped in the lungs.
(i) Shortness of breath
(ii) Fatigue
(iii) Recurrent respiratory infections
(iv) Weight loss

Q13. What is exhalation?
Ans. It takes place in the following way:
Relaxation of rib muscles and diaphragm
After the gaseous exchange in the lungs, the impure air is expelled out in exhalation. The ribs come back to the original position, the diaphragm muscles also relax and it gets its raised dome
Effect of relaxation
This reduces the space in the chest cavity and increases the pressure on lungs. The lungs contract and the air is expelled out of them.

Q14. What is gaseous exchange?
Ans. Taking in oxygen and giving out of carbon dioxide is termed as gaseous exchange.

Q15. What is inhalation?
Ans. It takes place in the following way:
Contraction of Rib muscles and diaphragm
During inhalation the rib muscles contract and ribs are raised. At the same time the dome shaped diaphragm contracts and is lowered.
Effect of contraction
These movements increase the area of the thoracic cavity, which reduces the pressure on lungs. As a result, the lungs expand and the air pressure within them also decreases. The air from outside rushes into the lungs to equalize the pressure on both sides.

Q16. Define Larynx?
Ans. The larynx is a box made up of cartilage. It is present between pharynx and trachea. It is also called voice box.

Q17. Define lenticels?
Ans. In woody stems and mature roots, there are certain pores in the layer of bark. The lenticels allow air to pass through them.

Q18. What is Nasal cavity?
Ans. The nose encloses the nasal cavity. The, nasal cavity is divided into two portions by a wall. Each portion is lined by fine hairs and mucous which filter the dust particles from the air. The mucous also moistens and warms the incoming air and keeps its temperature usually equal to that of the body.

Q19. Define Nostrils?
Ans. Nasal cavity opens to the outside through the openings called the nostrils.

Q20. What is pneumonia?
Ans. It is an infection of lungs.
Double Pneumonia
If this infection affects both lungs it is called double pneumonia.
The most common cause of pneumonia is bacterium Streptococcus pneumoniae. Some viral and fungal infections may also lead to pneumonia.

Q21. What is trachea?
Ans. Larynx continues to the trachea, which is also called the windpipe. It is about 12 cm long tube which lies in front of the oesophagus. There are C-shaped cartilagenous rings in the wall of trachea The cartilage keep the trachea from collapsing even when there is no air in it.

Q22. Define vocal cord?
Ans. Two pairs of fibrous bands called vocal cords are stretched across the larynx. The vocal cords vibrate when the air passes through them. This vibration produces sounds.

Q23. Define epiglottis. Write its function?
Ans. In the air passageway of man, the glottis is guarded by a flap of tissue is called epiglottis. Epiglottis closes the opening of glottis while swallowing in order to prevent entry of any food particle into it.

Q24. What are the symptoms of Bronchitis?
Ans. Symptoms of Bronchitis includes:
(a) Cough
(b) Mild wheezing
(c) Fever
(d) Chills
(e) Shortness of breath (Especially when doing hard job)

Q25. What is Larynx? Write its function?
Ans. Definition
The larynx is a box made of cartilage. It is also called the voice box. It is present between pharynx and trachea.
Two pairs of fibrous bands called vocal cords are stretched across the larynx. When the air passes through them, the vocal cords vibrate. This vibration produces sounds. Movements of lips, cheeks, tongue and jaws produce specific sounds which results in speech. Speech is an ability of only humans.

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1.The process of gaseous exchange involves:
(a) Breakdown of C-H bonds to yield energy
(b) Physical movements that take air in and out of body
(c) Getting oxygen from the air and removing carbon dioxide✅
(d) Transport of oxygen by the blood to different parts of the body

2.Most of the gaseous exchange in a leaf occurs through:
(a) Stomata✅
(c) Cuticle
(b) General surface
(d) Lenticels

3.How many bronchi are there in the air passageway?
(a) One
(c) Many
(b) Two✅
(d) None

4.Where does the gaseous exchange occur in humans?
(a) Pharynx
(c) Bronchi
(b) Trachea
(d) Alveoli✅

5.Which structure actively helps in taking the air out of lungs?
(a) Nasal cavity
(b) Bronchus
(c) Bronchiole
(d) Diaphragm✅

6.The primary chemical stimulus for breathing is the concentration of;
(a) Carbon dioxide in blood✅
(b) Oxygen in blood
(c) Carbon dioxide in muscles
(d) Oxygen in muscles

7.Point out the FALSE statement about respiration.
(a) Gases can easily pass through the walls of the alveoli
(b) Gas exchange in lungs is very efficient because lungs provide large surface area
(c) In emphysema, the walls of alveoli break and there is more surface area✅
(d) Dust particles can damage the lung by irritating the inner alveoli surface

8.A disease involving the breakdown of air sacs of the lungs is;
(a) Pneumonia
(c) Asthma
(b) Bronchitis
(d) Emphysema✅

9.Which process does not occur in the nasal cavity?
(a) Trapping of large dust particles
(b) Humidification of the inhaled air
(c) Warming of the inhaled air
(d) Exchange of gases✅

10.What type of blood vessels surrounds the alveoli?

(a) Artery
(c) Capillary✅
(b) Arteriole
(d) Vein

11.In which of the following gaseous exchange occurs through stomata?
(a) Leaves and young stems✅
(b) Woody stems and mature roots
(c) Young roots
(d) Aquatic plants

12.In humans and other higher animals,the exchange of gases is carried out by:
(a) Skin
(b) Respiratory surface
(c) Air passageway
(d) Lungs✅

13.The length of trachea is:
(a) 10 cm
(b) 12 cm✅
(c) 22 cm
(d) 20 cm

14.C-shaped cartilagenous rings are present in the wall of;
(a) Bronchi
(b) Alveoli
(c) Bronchioles
(d) Trachea✅

15.How many pairs of ribs are there in humans?
(a) 24
(b) 12✅
(c) 26
(d) None

16.How many lobes are present in right lung?
(a) 2
(b) 3✅
(c) 4
(d) 5

17.Which of the following is called voice box?
(a) Trachea
(b) Larynx ✅
(c) Bronchi
(d) Alveoli

18.The normal breathing rate in human being is:
(a) 10-40 times per minute
(b) 16-20 times per minute✅
(c) 30-40 times per minute
(d) None of these

19.During exercise or other hard physical works the breathing rate may increase up to:
(a) 30-40 times per minute✅
(b) 50-60 times per minute
(c) 50-55 times per minute
(d) 60-70 times per minute

20.Amount of oxygen in expired air is:
(a) 21%
(b) 16% ✅
(c) 0.04%
(d) 4%

21.Amount of carbon dioxide in inspired air is:
(a) 16%
(b) 0.04%✅
(c) 4%
(d) None

22.Amount of nitrogen in expired air is:
(a) 70%
(b) 80%
(c) 79%✅
(d) 4%

23.Cough, mild wheezing, fever, chills and shortness of breath (especially when doing hard job) are symptoms of:
(a) Emphysema
(b) Pneumonia
(c) Asthma✅
(d) Bronchitis

24.In which of the following disease, the patient has usually lost 50% to 70% of his/her lung tissue when symptoms appears?
(a) Pneumonia
(b) Asthma
(c) Emphysema✅
(d) Bronchitis

25.Pneumonia is an infection of:

(a) Kidneys
(b) Digestive system
(c) Lungs✅
(d) Blood

26.Which one is the form of allergy?
(a) Asthma✅
(b) Pneumonia
(c) Bronchitis
(d) Lung cancer

27.When the “World No Tobacco Day” is celebrated?
(a) 30 June
(c) 11 January
(b) 31 June
(d) None✅

28.Smoking may also lead to the cancers in:
(a) Kidneys and pancreas
(b) Oral cavity and larynx
(c) Breast and bladder
(d) All of the above✅

29.The destruction of wall of alveoli is called:
(a) Pneumonia
(b) Emphysema ✅
(c) Asthma

30.The inflammation of bronchi or bronchioles is called:
(a) Bronchitis✅
(b) Emphysema
(c) Pneumonia
(d) Asthma

31.Which remains unaffected in expired air?
(a) O2
(b) CO2✅
(c) N2
(d) Water vapours

32.In developing world smoking has:
(a) Decline
(b) Risen by 5.4%
(c) No effect
(d) Risen by 3.4%✅

33.In young stems and leaves some gaseous exchange occurs through
(a) Leaf petioles
(b) Cuticle✅
(c) Leaf petioles and cuticl
(d) Mesophyll

34.Exchange of gases occurs through lenticels in;

(a) Woody stems
(b) Mature roots
(c) Woody stems and mature roots✅
(d) Young stems

35.Gases diffuse by general surface in:
(a) All stems
(b) Young roots✅
(c) All leaves
(d) Mature roots

36.Air passageway starts from:
(a) Nose✅
(b) Pharynx
(c) Trachea
(d) Bronchi

37.A flap of tissue which guards glottis is:
(a) Larynx
(b) Epiglottis✅
(c) Pharynx
(d) Ribs

38.Temperature of expired air is:
(a) High
(b) Low
(c) Equal to the body temperature✅
(d) Equal to external environment

39.Cluster of pouches found respiratory system:

(a) Bronchi
(b) Alveoli✅
(c) Bronchioles
(d) Trachea

40.Lungs are organ which are;
(a) Spongy
(c) Spongy and elastic✅
(d) Tough

41.Dusky or purplish skin colour is a symptom of:
(a) Bronchitis
(b) Emphysema
(c) Pneumonia✅
(d) Asthma

42.Total chemicals in tobacco smoke are:
(a) 1000
(b) 2000
(c) 3000✅
(d) 4000

43.Tooth loss is times higher in smokers than in non-smokers.
(a) 2-5 times
(b) 1-2 times
(c) 2-3 times✅
(d) 4-5 times

44.Which of the following lessens the oxygen carrying of haemoglobin?

(a) Tar
(b) Carbon dioxide
(c) Nicotine
(d) Carbon monoxide✅

45.A powerful poison which damages brain is:
(a) Tar
(b) Nicotine✅
(c) Carcinogen
(d) Carbon monoxide

46.Function of pleural membrane is to:
(a) Hold the lungs in their correct position in cavity✅
(b) Help to increase the volume of cavity during respiration
(c) Increase volume of chest
(d) Secrete to help the lungs

47.Which one takes deoxygenated blood towards lungs
(a) Pulmonary artery✅
(b) Aorta
(c) Superior Vena cava
(d) Pulmonary vein

48.Asthma is caused by:
(a) Perfumes✅
(b) Vitamin B-12 deficiency
(c) Vitamin C deficiency
(d) Vitamin K deficiency

49.Some viral (Influenza virus) and fungal infections may also lead to:

(a) Asthma
(b) Pneumonia✅
(c) Lung cancer
(d) Emphysema

50.A thick muscular structure present below the lungs is called:
(a) Alveolus
(b) Tracheoles
(c) Diaphragm✅
(d) Bronchioles

51.The main cause of lung cancer is:
(a) Smoking✅
(b) Viral infection
(c) Bacterial infection
(d) Both viral and bacterial infection

52.Passive smoking in non-smokers has increased heart rate by:

(a) 20-30%
(c) 25-40%
(b) 25-30%✅
(d) 30-40%

53.Percentage of CO₂ in exhaled air during breathing is:

(a) 16%
(b) 4%
(c) 79%
(d) 0.04%

54.Rate of breathing depends upon concentration of which gas in the blood?
(a) Oxygen
(b) Carbon dioxide✅
(c) Nitrogen
(d) Hydrogen

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