From the chapter Respiration in Organisms, some of the important questions are covered in this question paper. The questions are covers from the Higher Order Thinking Questions and Value Based Questions

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Questions:

Generic 3

5 x 3 = 15

Observe the given diagram of human respiratory system. List the organs from (A) to (G).

After we work hard or perform physical activity, we feel hungry. Explain why

Why do we often sneeze when we inhale a lot of dust-laden air?

List the similarities and differences between aerobic and anaerobic respiration

Why does an athlete breathe faster and deeper than usual after finishing the race?

Multiple Choice Question

5 x 1 = 5

The raw material for cellular respiration is

(a)

glucose

(b)

sucrose

(c)

fructose

(d)

starch

Earthworms and frogs breathe through their skin because of which the skin of both the organisms is

(a)

moist and rough

(b)

dry and rough

(c)

dry and slimy

(d)

moist and slimy

Yeast is used in wine and beer industries because it respires

(a)

aerobically producing oxygen

(b)

aerobically producing alcohol

(c)

anaerobically producing alcohol

(d)

anaerobically producing CO2

During exhalation, the ribs

(a)

move outwards

(b)

move downwards

(c)

move upwards

(d)

do not move at all

10.

During heavy exercise, we get cramps in the legs due to the accumulation of

(a)

carbon dioxide

(b)

lactic acid

(c)

alcohol

(d)

water

True or False

5 x 1 = 5

11.

We take deep breathes after we hold on breath for the one minute.

(a)

False

(b)

True

12.

Living organism respire to get energy from food.

(a)

False

(b)

True

13.

Insects have spiracles on the lower surface of the body.

(a)

True

(b)

False

14.

The size of the chest cavity increases during inhalation.

(a)

False

(b)

True

15.

Plants carry out photosynthesis only during the day and respiration only at night.

(a)

True

(b)

False

Generic 2

5 x 2 = 10

16.

Explain cellular respiration.

17.

Certain small pores are present on the surface of plant through which gaseous exchange occurs. Identify these pores?

18.

In the experiment, where we exhale into lime water containing glass. What changes were observed by you?

19.

Our nostrils has hair and mucous. What is the need to have them in our nasal cavity?

20.

The cellular respiration process takes place in which cell organelle?

Generic 5

2 x 5 = 10

21.

It is not wise to sleep under a tree during night. Why?

22.

A food stall owner was preparing dough for making bhaturas. He added a pinch of yeast and sugar to the dough and left it in a warm place. After few hours, the dough had risen. There was a sour smell too.
(a) Why did the dough rise?
(b) Why did the dough smell sour?
(c) Why was sugar added to the dough?
(d) What would have happened if the dough was kept in the refrigerator, soon after it was prepared?

Fill up / 1 Marks

5 x 1 = 5

23.

Lungs are very..............organ

24.

Taking in of air rich in O₂ inside the body is called _____

25.

................is an essential phenomenon for the survival of living organisms

26.

Exchange of gases in the leaves takes place with the help of...........

27.

Diaphragm forms the.............. of the chest cavity.

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Answers Key:

Generic 3

5 x 3 = 15

The human respiratory system have following organs:
A- Ribs
B- Trachea
C- Pharynx
D - Diaphragm
E- Lungs
F- Nasal passage
G- Oral cavity

When we work hard or perform physical activity (like running, swimming, cycling), we need more energy. To fulfil the energy requirement, we breathe faster. Fast breathing helps in supply of more oxygen to our cells. Due to this, rate of breakdown of food increases and more energy is released. The rapid breakdown of food makes us to feel more hungry.

When we inhale dust-laden air, dirt-particles are captured within the nostrils. Sometimes, they get past the nostril hair in the nasal cavity and irritate the lining of the cavity, as a result, we sneeze. Sneezing expels these foreign particles from the inhaled air and a dust free, clean air enters in our body

Differences between aerobic and anaerobic respiration are as follows

Aerobic respiration	Anaerobic respiration
It uses oxygen	It takes place in the absence of oxygen
Glucose is completely broken down into Co₂ and water along with release of high amount of energy	Glucose is broken into ethyl alcohol or lactic acid CO₂ and energy produced is in low amount
It occurs in all living organisms like mammals	It occurs in lower organisms like yeast, fungi and bacteria
Glucose + O₂ \(\rightarrow\) co₂ + H₂O₂ + Energy	Glucose \(\rightarrow\) ethyl alcohol + Co₂ + Energy

Similarities between aerobic and anaerobic respiration are as follows
(i) Both break down the glucose.
(ii) Release of energy takes place in both.
(iii) CO2 is the common product in both.

Our body needs energy for all activitie, while doing heavy exercises like running and there is a larger demand of energy to perform these activities. Hence, more oxygen is required to meet extra demand of energy. Therefore, an athlete breathes faster and deeper than usual after finishing the race

Multiple Choice Question

5 x 1 = 5

(a)
glucose

(d)
moist and slimy

Move downwards During exhalation the ribs moves downwards causing a decrease in area of chest cavity forcing the air out.

10.

Lactic acid It is produced during heavy exercise as sufficient oxygen is not available to muscles.

True or False

5 x 1 = 5

11.

(a)
False

12.

(a)
False

13.

(b)
False

14.

(a)
False

15.

(b)
False

Generic 2

5 x 2 = 10

16.

The process of braeak down of food in the cell with the release of energy is called cellular respiration

17.

Stomata are the tiny pores that are present on the surface of plant through which gaseous exchange occurs.

18.

When we exhale into lime water its colour changes, into slightly milky white because exhaled air contains CO₂,

19.

Our nostrils possess hairs and mucous lining. These help in preventing dirt, dust and germs from entering our respiratory system.

20.

Cellular respiration takes place in the mitochondria of the cell

Generic 5

2 x 5 = 10

21.

During day, plants photosynthesise in the presence of sunlight and uses CO₂ produced during respiration. During this process O₂ is released as a byproduct and a balance between O₂ and CO₂ is maintained in the atmosphere. But in the night. plants do not photosynthesise. Plants are unable to use CO2 during night and produces CO₂ and takes O₂ during respiration. This leads to the increase in the proportion of CO₂ in the air.
So, if one sleeps under a tree at night. he will have problems in breathing as the amount of CO₂ in the air around will certainly be more than oxygen. Therefore, it is not advisable to sleep under trees during night because the person will suffer from suffocation and feel excess weight on chest.

22.

(a) The dough rises due to the release of carbon dioxide during anaerobic respiration by yeast cell.
(b) Yeast, during anaerobic respiration also produces alcohol which results in the sour smell of dough.
(c) Sugar is added into the dough, because it acts as a food for yeast. Yeast upon incomplete breakdown of sugar or food produces CO₂, alcohol and energy (in less amount).
(d) If the dough is kept in the refrigerators after it was prepared, then dough will neither raise nor become sour. Yeast requires high temperature to grow, multiply and to respire. At low temperature, the yeast will not respire to produce the byproducts of anaerobic respiration.

Fill up / 1 Marks

5 x 1 = 5

23.