CBSE Class 10 Biology Life Processes Respiration Worksheet Set B

Fill in the following blanks with suitable words :

(a) The organs of respiration in man are the.................
Answer : lungs

(b) The actual exchange of gases takes place in the................of the lungs.
Answer : alveoli 

(c) ..................in the lungs provide a very large surface area for gaseous exchange.
Answer : Alveoli 

(d) Yeast undergoes.................respiration whereas Amoeba undergoes..................respiration.
Answer : anaerobic; aerobic

(e) Gills are the breathing organs in................
Answer : fish 

Short Answer Type Questions

Question. Explain why, a land plant may die if its roots remain waterlogged for a long time.
Answer : The land plants may die if roots remain waterlogged for a long time because roots also respire if water is logged for much time then the process of diffusion will not occur in the roots. The roots present in the soil gets logged with waters and the air spaces of roots get filled with bubbles and decline the plants to respire and the plant dies.

Question. What type of respiration takes place in human muscles during vigorous physical exercise ? Give reason for your answer.
Answer : Anaerobic type of respiration takes place in human muscles during vigorous physical exercise.
During heavy physical exercise, the body needs more energy than usual but the energy produced by aerobic respiration is insufficient to fulfill the body requirement, so muscles cells respire anaerobically to release energy.

Question. Name the type of respiration in which the end products are :
(a) C2H5OH and CO2
(b) CO2 and H2O
(c) Lactic acid
Give one example of each case where such a respiration can occur.
Answer : (a) Anaerobic respiration in yeast (b) Aerobic respiration (c) Anaerobic respiration in muscle tissue of animals

Question. What are the different ways in which glucose is oxidised to provide energy in various organisms ? Give one example of each.
Answer :∙ The breakdown of glucose involved into main processes:
∙ Glycolysis: It is the process in which 6 molecules of carbon break to form two molecules of pyruvate containing 3 carbon in each.
∙ Further, the pyruvate molecule breaks down to form energy in different ways in various organisms:
∙ Aerobic respiration: It is the process in which pyruvate molecules break down to form water and carbon dioxide by releasing energy.
∙ Anaerobic respiration: It is the process in which pyruvate molecule breakdowns in the absence of oxygen which give rise to carbon dioxide, water and ethanol. 

Question. Explain why, when air is taken in and let out during breathing, the lungs always contain a residual volume of air.
Answer : Residual volume:
Residual volume is the amount of gas remaining in the lungs at the end of a maximal exhalation.
If the lungs removed all the air from itself while exhaling the air out of the system, it would collapse because the entire muscle would come together while contracting.
Residual volume is important because it prevents the lungs from collapsing.
Even after we have expelled as much air as possible (expiratory reserve volume) gaseous exchange is still occurring by residual volume in the lungs.
It also prevents the inner surfaces of the lungs from sticking together.

Question. Explain why, it is dangerous to inhale air containing carbon monoxide.
Answer : Carbon monoxide (CO) is dangerous to our body ,when we inhales air which contain carbon monoxide, it displaces oxygen in the blood and deprives the heart, brain, and other vital organs of oxygen. Large amounts of CO can overcome you in minutes without warning—causing you to lose consciousness and suffocate.
When carbon monoxide is inhaled, it takes the place of oxygen in hemoglobin, the red blood pigment that normally carries oxygen to all parts of the body. Because carbon monoxide binds to hemoglobin several hundred times more strongly than oxygen, its effects are cumulative and long-lasting, causing oxygen starvation throughout the body. Prolonged exposure to fresh air (or pure oxygen) is required for the CO-tainted hemoglobin (carboxyhemoglobin) to clear.

Question. Describe the process of respiration in Amoeba. State whether it is anaerobic respiration or aerobic respiration.
Answer : In amoeba respiration takes place through its cell membrane also called the plasma membrane. Amoeba gets oxygen gas dissolved in surrounding water through its plasma membrane by the process of diffusion. The oxygen gas diffused inside the body is used up by the amoeba. In the body, the oxygen gas absorbed is used to break down the complex food material into simple molecules. During these metabolic reactions in the body of amoeba, the oxygen gas is converted into carbon dioxide gas.

Question. State the three common features of all the respiratory organs like skin, gills and lungs.
Answer : All the respiratory organs have a large surface area to get enough oxygen.
All the respiratory organs have thin walls for easy diffusion and exchange of respiratory gases.
All the respiratory organs such as skin, gills and lungs, have a rich blood supply for transporting respiratory gases

Question. Describe the process of respiration in fish.
Answer : Respiration in fish takes with the help of gills. Most fish possess gills on either side of their head. Gills are tissues made up of feathery structures called gill filaments that provide a large surface area for gas exchange. Fish take in oxygen-rich water through their mouths and pump it over their gills. 

Question. What would be the consequences of deficiency of haemoglobin in our bodies ?
Answer : Consequences of a deficiency of hemoglobin:
Hemoglobin is a pigment that is helpful in supplying oxygen in all the parts of the body through blood.
It is present in the red blood cells and acts as a carrier of oxygen.
The deficiency of hemoglobin makes an individual anemic which means fewer red blood cells.
The deficiency of hemoglobin will decrease the oxygen-carrying capacity of the blood.
A decrease in hemoglobin in blood will lead to slow functioning of body parts and weakness due to the less supply of oxygen.

Question. Describe the process of respiration in the following parts of a plant :
(a) Root (b) Stem (c) Leaves
Answer : (a) Through roots:
Roots of plant respire by taking air trapped in the soil using epidermal growth called root hairs. Once the exchange of gases is done, then the process of respiration in same in every part of plants.
(b)Through stems:
Lenticels are the lens-shaped small pores on the surface of the stems of woody plants. Lenticels consist of thin-walled loosely arranged cells with intercellular spaces. In the stem, they help in gaseous exchange.
(c)Respiration through leaves:
The leaves of plants have tiny pores called stomata which help in gaseous exchange by simple diffusion process. The rate of respiration in plants is much slower than animals as the energy requirement of the animals is low. During daytime when photosynthesis is also going on in the leaves, oxygen for respiration is obtained by photosynthesis itself while excess oxygen is given out. During night time, when there is no photosynthesis stomata take in oxygen and give out carbon dioxide as all organisms. Once oxygen is inside the cells of the leaves glucose is oxidised to release energy in the form of ATP molecules and is used for various metabolic activities.

Question. (a) What is meant by aquatic animals and terrestrial animals ?
(b) From where do the aquatic animals and terrestrial animals obtain oxygen for breathing and respiration ?
Answer : (a)Aquatic animals are the animals which survive in water. They can't survive if they are out of the water. Example:- fishes, Dolphins
Terrestrial animals are the animals which survive on the earth. Example:- tiger, lion.
(b) Aquatic animals get oxygen which is dissolved in water.
Terrestrial animals get oxygen that is released into the atmosphere by the green plants.

Question. Why do fishes die when taken out of water ?
Answer : ∙Fish breathe through gills which are filled with blood capillaries that absorb the oxygen dissolved in the water.
∙When the fish is present inside the water it takes off the dissolved oxygen and releases carbon dioxide by mouth.
∙When the fish is taken out of the water, it cannot breathe and the supply of oxygen is reduced because the cannot use oxygen present in the atmosphere.
∙Due to which the fishes die when they are taken out of the water.

Question. Why is the rate of breathing in aquatic organisms much faster than in terrestrial organisms ?
Answer : Aquatic organisms like fishes obtain oxygen from water present in dissolved state through their gills. Since the amount of dissolved oxygen in water is fairly low compared to the amount of oxygen in the air, the rate of breathing in aquatic organisms is much faster due to the low concentration of oxygen in the aquatic environment than that seen in terrestrial organisms.

Question. Name the energy currency in the living organisms. When and where is it produced ?
Answer : ATP

Question. Explain why, plants have low energy needs as compared to animals.
Answer : Plants do not need to move from one place to another. Movements in a plant are usually at the cellular level and hence a far less amount of energy is required by plants. Animals, on the other hand, need to move from one place to another; in search of food. So, the energy need of animals is pretty higher than of plants.

Question. Explain how, it would benefit deep sea divers if humans also had gills.
Answer : The deep sea divers could remain under sea water even without carrying oxygen cylinders for breathing (because they could then extract dissolved oxygen from water for breathing purpose just like fish)