Life Process - Lakhmir Singh Manjit Kaur Solutions Pg No. 74 Class 10 Biology

Solutions of Life Process Lakhmir Singh Manjit Kaur LAQ, HOTS and MCQ Pg No. 74 Class 10 Biology

Solutions of Life Process Lakhmir Singh Manjit Kaur LAQ, HOTS and MCQ Pg No. 74 Class 10 Biology

Long Answer Type Questions-Pg-74

50A. What is blood? Why is it red?

Answer

→ Blood is a red coloured fluid which circulates throughout the body. It consists of 55% plasma and 45% blood cells. Blood is red in colour because it contains a pigment called haemoglobin in its red cells (RBC).

50B. State the functions of blood in our body.

Answer

→ The functions of blood:
(i) Transport oxygen from the lungs to different parts of the body.
(ii) Transport CO2 from the body tissues to the lungs.
(iii) Transport digested food i.e., glucose, amino acids, etc. from alimentary canal to various parts of the body for energy, growth and repair.
(iv) Transport excretory waste product called urea from the liver to the kidneys for removal as urine.
(v) Plasma regulates water balance in the body.
(vi) Regulates the body temperature.

50C. Name a circulatory fluid in the human body other than blood.

Answer

→ Lymph is a circulatory fluid in the human body other than blood.

51A. What is meant by human circulatory system? Name the organs of the circulatory system in humans.

Answer

→ The organ system which is responsible for the transport of materials inside the human body is called human circulatory system. Heart is the main organ of the human circulatory system. The other organs of the human circulatory system include arteries, veins and capillaries.

51B. Draw a diagram of the human heart and label its parts.

Answer



51C. What is meant by the terms 'single circulation' and 'double circulation'?

Answer

→ the case of single circulation, blood passes through the heart only once in one complete cycle of the body whereas in double circulation, blood passes through the heart twice in one complete cycle of the body.

52. Describe the working of human blood circulatory system with the help of a suitable diagram which shows all the steps involved.

Answer

→ Following steps are included in the functioning of human circulatory system:

(i) The pulmonary vein brings the oxygenated blood from the lungs in the left atrium of the heart.
(ii) Left atrium contracts and pumps blood into the left ventricle through valve.
(iii) When the left ventricle contracts, the oxygenated blood enters the main artery called aorta. The blood travels from the main artery to larger and smaller arteries into the capillary network.
(iv) The aorta transports the blood to all the organs of the body except the lungs. The oxygenated blood releases oxygen, nutrients and other substances and takes on carbon dioxide and waste substances. The deoxygenated blood enters the vena cava which carry it to the right atrium of the heart.
(v) Right atrium pumps deoxygenated blood into the right ventricle through the valve.
(vi) When the right ventricle contracts, the deoxygenated blood enters the lungs through pulmonary artery and releases carbon dioxide and absorbs fresh oxygen from air. The blood becomes oxygenated again and is sent to the left atrium of heart by pulmonary vein for circulation in the body. This whole process is repeated continuously.
Picture

53A. Name the red pigment which carries oxygen in the blood.

Answer

→ Haemoglobin is a respiratory pigment, found in the red blood cells which carries oxygen in the blood.

53B. Why is it necessary to separate oxygenated and deoxygenated blood in mammals and birds?

Answer

→ Mammals and birds are warm-blooded animals. They require more energy to maintain their body temperature, so they require more oxygen to produce energy. Thus, it is necessary that their oxygenated blood get separated with deoxygenated blood.

53C. How many chambers are there in the heart of: (i) an amphibian, (ii) a mammal, and (iii) a fish?

Answer

→ (i) Thee chamber heart is found in amphibians.
(ii) Four chambered heart is found in mammals.
(iii) Two chambered heart is found in fishes.

 53D. Describe the circulatory system in a fish.

Answer

→ Fish has a two-chambered heart-one atrium and one ventricle. In fish, heart pumps blood to the gills where oxygenation of blood takes place. The gills send the oxygenated blood to all the parts of the fish where oxygen is utilized and carbon dioxide enters into it making it deoxygenated. The deoxygenated blood is transported to the heart where it is pumped into the gills.

54A. What is lymphatic system ? What are its functions?

Answer

→ Lymphatic system is a system of tiny tubes called lymph vessels (lymphatics) and lymph nodes (lymph glands) in the human body which transports the liquid called lymph from the body tissues to the blood circulatory system.

The functions of lymphatic system are:
(i) It helps in removing the waste products.
(ii) It carries digested fat from the small intestine to the entire body.
(iii) Lymph nodes contain lymphocytes which kill the germs or foreign bodies.

54B. What is blood pressure? What are the two factors used to express the blood pressure of a person?

Answer

→ The pressure of blood which is exerted on the walls of blood vessels is called blood pressure. This pressure is much greater in the arteries than in the veins. The blood pressure of a person is always expressed by two factors - systolic pressure and diastolic pressure.

54C. Name the main nitrogenous waste in the human blood. How is it removed from the blood?

Answer

→ The main nitrogenous waste in the human blood is urea. It is removed from the blood by the kidney in the form of urine.

55A. Name the various organs of the human excretory system.

Answer

→ The excretory system of human beings consists: two kidneys, two ureters, a urinary bladder and a urethra.

55B. Draw a neat labelled diagram of the human excretory system.

Answer


55C. What is the function of excretory system in humans?

Answer

→ The primary function of excretory system, in humans, is to remove the nitrogenous wastes such as urea from the body and maintain mineral balance in the blood.

56A. Describe the mechanism of urine formation in human excretory system. Draw a labelled diagram to illustrate your answer.

Answer

→ Urine formation: Urine is formed inside the kidney in the nephron. Nephron is a functional unit of kidney. The blood containing waste like urea enters the glomerulus which filters the blood. Water, urea, and other salts like glucose are filtered out in renal tubule. The filtered fluid is called glomerular fluid. When the filtrate containing useful substances as well as the waste substances passes through the tubule, the useful substances like glucose, amino acids, most salts and water are reabsorbed into the blood through blood capillaries surrounding the tubule. Certain substances which are harmful and not needed by the body like urea, remain behind in the tubule. This yellowish liquid is called urine.


56B. Where is urine carried through ureters?

Answer

→ Ureters carry urine from kidneys to bladder.

56C. What is urethra?

Answer

→ Urethra is a muscular tube through which the urine collected in the urinary bladder is passed out from the body.

57A. What is meant by dialysis? What type of patients are put on dialysis ?

Answer

→ Dialysis is a procedure by which blood of a person is cleaned by separating the urea from it. The patients with kidney failure are put on dialysis.

57B. Explain the principle of dialysis with the help of a labelled diagram.

Answer

→ In the process of dialysis, the blood from an artery in the patient’s arm is taken and is made to flow into the dialyser of a dialysis machine. The dialyser is made of long tubes of selective permeable membrane (like cellulose) which are coiled in a tank containing dialysing solution. The dialysing solution is a mixture of water, glucose and salts present in same concentrations as those of normal blood. As the blood passes through the dialysing solution most of the wastes like urea present in it pass through the selectively permeable cellulose tubes into the dialyzing solution. The purified blood is then pumped back into a vein of the patient’s arm.


58A. Why is transport of materials necessary in an organism (plant or animal) ?

Answer

→ All living organisms (plant and animals) need water, food and oxygen for their survival and to perform various activities. They need to transport all these materials to various parts of their body.

58B. What is the need of special tissues or organs for transport of substances in plants and animals?

Answer

→ Plant and animals needs special tissue and organs for the transport of substances because essential substances like water, food and oxygen are made (or absorbed) in one part of the body and carried to other parts of the body.

58C. How are water and minerals transported in plants ?

Answer

→ Xylem tissue transports water and minerals in plants from the soil to leaves. Xylem vessels and tracheids are elements of xylem tissues. They are interconnected in roots, stem and leaves and form a continuous system of water-conducting channels reaching all parts of the plant. Plants take in water from the soil through the roots. The roots have root hairs to absorb water and minerals from the soil by diffusion. Each root hair is single-celled structure. The absorbed water and minerals passes from cell to cell by osmosis through epidermis, root cortex, endodermis and then reach the root xylem. The water enters the root xylem into the stem xylem and then reaches the leaves from the petioles.


58D. How is food transported in plants?

Answer

→ The food is manufactured in the leaves by photosynthesis and carried out from the leaves to the other parts of the plant. The transport of food from the leaves to other parts of the plant is called translocation. It is done through a vascular tissue called phloem. The translocation of food takes place in the living cells called sieve tubes with the help of the adjacent companion cells. The translocation of food in phloem takes place by utilizing energy. The food, prepare in the leaves, is loaded into the sieve tubes of the phloem tissue using energy ATP. The water now enters the sieve tube having sugar which causes high pressure and pushes the food to all the parts of the plant having low pressure. This allows the phloem to transport food according to the plant’s needs.

Multiple Choice Questions (MCQs)-Pg-75

59. One of the following does not have a nucleus. This one is :
A. red blood cell
B. white blood cell
C. guard cell
D. epidermal cell

Answer


→ Red blood cell red in colour because of the presence of a pigment called haemoglobin. It does not have a nucleus.

60. The component 'of blood which makes chemicals known as antibodies is :
A. platelets
B. white blood cells
C. red blood cells
D. plasma

Answer

→ Which blood cells (WBC), a component of blood, protect us from diseases. WBC make a chemical, antibodies which help to fight against infection.

61. An animal in which the oxygenation of blood does not take place in the lungs is :
A. cow
B. fish
C. frog
D. fox

Answer

→ Fish has gills to oxygenated its blood. The oxygenated blood is supplied from the gills to the body.

62. Which of the following carries substances upwards as well as downwards in a plt ?
A. xylem
B. companion cells
C. phloem
D. tracheids

Answer

→ Phloem is a vascular tissue which transports food substances from the leaves to the other parts of the plant body. It transports in both the directions upward as well as downward.

63. One of the following is not a constituent of blood. This one is :
A. red blood cells
B. white blood cells
C. sieve plates
D. platelets

Answer

→ The blood is made up of plasma and blood cells (RBC, WBC and platelets). Sieve plate is a part of plant vascular system.

64. If a patient is put on dialysis, he is most likely suffering from a severe ailment of the :
A. circulatory system
B. respiratory system
C. excretory system
D. digestive system

Answer

→ Some people need to use a dialysis machine because one or both of their kidneys fail to work. Dialysis machine cleans the blood of a person by removing the nitrogenous wastes from the blood.

65. Water absorption through roots can be increased by keeping the potted plants :
A. in the shade
B. in dim light
C. under the fan
D. covered with a polythene bag

Answer

→ When we place a plant place under the fan, the speed of air flow is very high. Transpiration will take place in the presence of high air flow through the stomata. The rate of transpiration increases during windy condition.

66. A blood vessel which carries blood back to the heart is:
A. artery
B. vein
C. capillary
D. platelet

Answer

→ Vein is a thin-walled blood vessels which carries blood back to the heart.

67. Blood is pumped from the heart to the entire body by the:
A. lungs
B. ventricles
C. atria
D. nerves

Answer

→ In human, heart has two ventricles-right ventricle and left ventricle. The function of ventricles is to pump blood from the heart to the entire body.

68. The blood leaving the tissues becomes richer in :
A. carbon dioxide
B. water
C. haemoglobin
D. oxygen

Answer

→ The blood leaving the tissues becomes richer in carbon dioxide. When the oxygenated blood passes through the capillaries of the tissue, it gives oxygen to the body cells and takes carbon dioxide, produced during respiration. Thus, it becomes richer in carbon dioxide.

69. What prevents the back flow of blood inside the heart during contraction?
A. thick muscular walls of ventricles
B. valves
C. thin walls of atria
D. all of the above

Answer

→ Valves prevent the backflow of blood inside the heart during contraction. They allow the flow of blood in only one direction.

70. Which of the following is the correct path taken by urine in our body?
A. kidney  ureter  urethra  bladder
B. kidney  bladder  urethra ureter
C. kidney  ureter  bladder  urethra
D. bladder  kidney  ureter  urethra

Answer

→ Urine formation takes place inside the kidney. Ureter carries urine from kidneys to bladder. Bladder stores the urine temporarily. Then the urine is discharged out of the body through urethra.

71. In which of the following vertebrate group/groups, heart does not pump oxygenated blood to different parts of the body ?
A. pisces and amphibians. 
B. amphibians and reptiles
C. amphibians only
D. pisces only

Answer

→ In only pisces (fish) heart does not pump oxygenated blood to different parts of the body. The oxygenated blood is supplied from the gills to the body by dorsal aorta. Thus, in fish, heart receives only deoxygenated blood.

72. Which vein brings clean blood from the lungs into the heart?
A. renal vein
B. pulmonary vein
C. vena cava
D. hepatic vein

Answer

→ Pulmonary vein brings oxygenated blood from the lungs into the heart.

73. Which blood vessel does not carry any carbon dioxide ?
A. pulmonary artery
B. vena cava
C. hepatic vein
D. pulmonary vein

Answer

→ Pulmonary vein does not carry any carbon dioxide. It brings oxygenated blood from the lungs into the heart.

74. It has been found that people living in very high mountains have many more red corpuscles in their blood than people living in plains. Which one of the following best accounts for this phenomenon?
A. the cold climate stimulates the production of red corpuscles to keep the body warm
B. people of high mountains breathe more quickly
C. the low air pressure requires more red corpuscles to supply the body cells with oxygen.
D. the low air pressure in high mountains speeds up the blood circulation so that more red corpuscles are needed

Answer

→ At higher altitudes, the atmospheric pressure is low and hence body doesn’t get enough oxygen. This leads to many symptoms. More the number of RBC, more is the amount of oxygen that circulates in the body. Thus, to increase amount of oxygen, at low pressure, more RBC is required in the blood.

75. The phloem tissue in plants is responsible for the transport of :
A. water
B. water and minerals
C. sugar
D. all of the above

Answer

→ Phloem is a vascular tissue which transports food materials from leaves to the other parts of the plant.

76. Which of the following has a three-chambered heart?
A. pigeon
B. lizard
C. fish
D. lion

Answer

→ Cold blooded animals like amphibians and reptiles have three chambered heart.

77. In which of the following are the largest amounts of nitrogen excreted from a mammalian body ?
A. breath
B. sweat
C. urine
D. faeces

Answer

→ Kidneys excrete the nitrogenous waste like urea from the body in the form of urine.

78. Which one of the following has cytoplasm but no nucleus :
A. xylem vessel
B. sieve tube
C. tracheid
D. companion cell

Answer

→ The cells of phloem are called sieve tubes. These are living cells which contain cytoplasm but no nucleus.

79. The process of carrying food from the leaves to other parts of a plant is called :
A. transpiration
B. transportation
C. translocation
D. transformation

Answer

→ The process by which phloem carries food from the leaves to other parts of a plant is called translocation.

80. Which of the following is the only conducting tissue in non-flowering plants?
A. xylem vessels
B. sieve tubes
C. companion cells
D. tracheids

Answer

→ Tracheids are non-living cells which are present in all the plants but they are only water conducting tissue in non-flowering plants.

81. Which of the following helps in the upward movement of water and dissolved minerals from the roots to the leaves through the stem ?
A. transportation
B. translocation
C. tropic movement
D. transpiration

Answer

→ Transpiration helps in the upward movement of water and dissolved minerals from the roots to the leaves through the stem

82. Which one of the following does not have valves ?
A. heart
B. arteries
C. capillaries
D. veins

Answer

→ Capillaries are thin walled and extremely narrow blood vessels which do not have valves.

83. Which of the following is accomplished in a plant by utilizing the energy stored in ATP?
A. transport of food
B. transport of water and minerals
C. transport of oxygen
D. transport of water, minerals and food

Answer

→ The translocation of food in the phloem takes place by utilizing the energy stored in ATP.

84. Coagulation of blood in a cut or wound is brought about by :
A. plasma
B. platelets
C. WBC
D. RBC

Answer

→ The main function of platelets is to prevent bleeding. Platelets helps in the coagulation of blood (clotting of blood) in a cut or wound.

85. The blood vessel which carries oxygenated blood from the lungs to the heart is :
A. main artery
B. pulmonary artery
C. main vein
D. pulmonary vein

Answer

→ Pulmonary vein carries oxygenated blood from the lungs to the heart.

86. The instrument for measuring blood pressure is called :
A. manometer
B. sphygmomanometer
C. barometer
D. potentiometer

Answer

→ The blood pressure is measured with an instrument called sphygmomanometer.

87. The excretory unit in the human excretory system is called:
A. nephron
B. neuron
C. nephridia
D. kidney

Answer

→ The functional unit of human excretory system is nephrons. Urine formation takes place in nephrons of kidneys.

88. The substance which is not reabsorbed into the blood capillaries surrounding the tubule of a nephron is mainly :
A. glucose
B. amino acid
C. urea
D. water

Answer

→ As the glomerular filtrate passes through the tubular part of the nephron, the useful substances such as glucose, amino acids, salts and water are reabsorbed by the blood capillaries surrounding the nephron and only the waste substances such as urea and excess water remain behind in the tubule.

89. The procedure of cleaning the blood of a person by using a kidney machine is known as:
A. ketolysis
B. hydrolysis
C. dialysis
D. photolysis

Answer

→ Dialysis is the procedure of cleaning the blood of a person by using a kidney machine.

90. The excretory organs in an earthworm are:
A. nephridia
B. nephrons
C. raphides
D. ureters

Answer

→ In earthworm, excretory organs are nephridia.

91. The cells in our blood which destroy disease-causing germs, are :
A. platelets
B. skin cells
C. RBCs
D. WBCs

Answer

→ Which blood cells (WBC), a component of blood, protect us from diseases. WBC make a chemical, antibodies which help to fight against infection.

92. The wave of expansion of an artery when blood is forced into it is called :
A. flow
B. heart beat
C. pulse
D. ticking

Answer

→ Pulse is a wave of expansion of an artery when blood is forced into it.

93. In autotrophs, water is transported through:
A. root hair
B. phloem
C. stomata
D. xylem

Answer

→ Xylem is a vascular tissue in plants which carries water and minerals from the roots to the various of the plant.

94. An animal having double circulation in a three-chambered heart is:
A. fish
B. snake
C. deer
D. sparrow

Answer

→ Cold blooded animals like amphibians and reptiles have three chambered heart.

Questions Based on High Order Thinking Skills (HOTS)-Pg-76

95. The transport system in plants consists of two kinds of tissues X and Y. The tissue X is made up of living cells and consists of two components A and B. The component A has tiny pores in its end walls and contains only cytoplasm but no nucleus. On the other hand, component B has cytoplasm as well as nucleus. The tissue Y is made up of dead cells and consists of two components C and D. The component C has open ends whereas component D does not have open ends. In flowering plants, either only C or both C and D transport water but D is the only water conducting tissue in non-flowering plants.
(a) What is (i) tissue X (ii) component A, and (iii) component B ?
(b) What is (i) tissue Y (ii) component C, and (iii) component D ?

Answer

→ (a) (i) Phloem (X)
(ii) Sieve tube (A) (iii) Companion cell (B)
(b) (i) Xylem (Y) (ii) Xylem Vessel (C) (iii)Tracheids (D)

96. Water and dissolved minerals get into the root hair of a plant by a process called A and enter the conducting tissue B. The process C helps the water and dissolved minerals to move up through the tissue B in roots and stem, and reach the leaves of a plant. In the leaves food is made by a process D. This food is then transported to all the parts of a plant through tissue E. The process of distributing food made in the leaves to all the parts of the plant is called F.
(a) What are (i) A (ii) B (iii) C (iv) D (v) E, and (vi) F ?
(b) Which tissue is made up of living cells : B or E ?
(c) Which tissue, B or E, contains sieve tubes?
(d) Which tissue, B or E, contains tracheids ?

Answer

→ (a) (i) Diffusion (A) (ii) Xylem (B) (iii)Transpiration (C)
(iv) Photosynthesis (D)
(v) Phloem (E)
(vi) Translocation (F)
(b) E (c) E (d) B

97. The liquid connective tissue A circulates in our body continuously without stopping. This tissue contains a pigment B which imparts it a colour C. The tissue A consists of four components D, E, F and G. The component D fights infection and protects us from diseases. The component E helps in the clotting of tissue A if a person gets a cut. The component F is a liquid which consists mainly of water with many substances dissolved in it and component G carries oxygen from the lungs to all the parts of the body.
(a) What is (i) tissue A (ii) pigment B, and (iii) colour C ?
(b) Name (i) D (ii) E (iii) F, and (iv) G.
(c) Name one substance (other than oxygen) which is transported by tissue A in the human body.
(d) Which two components of tissue A are the cells without nucleus ?
(e) Name any two organisms (animals) which do not have liquid like A in their body.

Answer

→ (a) (i) Blood (A) (ii) Haemoglobin (B) (iii)Red (C)
(b) (i) White blood cells (D) (ii) Platelets (E) (iii)Plasma (F) (iv) Red Blood Cells (G)
(c) Digested Food
(d) E (Platelets) and G (Red Blood Cells)
(e) Amoeba and Grasshopper

98. The human body has an organ A which acts as a double pump. The oxygenated blood coming from the lungs through a blood vessel B enters the upper left chamber C of the double pump. When chamber C contracts, then blood goes into lower left chamber D. The contraction of chamber D forces the blood to go into a blood vessel E which supplies oxygenated blood to all the organs of the body (except the lungs). The deoxygenated blood coming out of the body organs is taken by a blood vessel F to the right upper chamber G of pumping organ. Contraction of Chamber G forces the deoxygenated blood into right lower chamber H. And finally the contraction of chamber H sends the deoxygenated blood into lungs through a blood vessel I.
(a) What is organ A ?
(b) Name the blood vessel (i) B (ii) E (iii) F, and (iv) I.
(c) What are chambers (i) C, and (i) D?
(d) What are chambers (i) G and (ii) H ?

Answer

→ (a) Heart (A)
(b) (i) Pulmonary Vein (B) (ii) Aorta (E) (iii) Vena cava (F)
(iv)Pulmonary artery (I)
(c) (i) Left atrium (C) (ii) Left ventricle (D)
(d) (i) Right atrium (G) (ii) Right ventricle (H)

99. A liquid X of colour Y circulates in the human body only in one direction : from body tissues to the heart.
Among other things, liquid X contains germs from cells and dead cells. The liquid X is cleaned of germs and dead cells by a special type of white blood cells called Z. This cleaned liquid is then put into blood circulatory system in subclavian veins.
(a) What is (i) liquid X, and (ii) colour Y ?
(b) What are Z ?
(c) The liquid X is somewhat. similar to a component of blood. Name this component.
(d) Why is liquid X not red ? .

Answer

→ (a) (i) Lymph (X) (ii) Light yellow (Y)
(b) Lymphocytes (Z)
(c) Plasma (C)
(d) Lymph (X) does not contain red blood cells having the red pigment called haemoglobin.

100. There is a pair of bean-shaped organs P in the human body towards the back, just above the waist. A waste product Q formed by the decomposition of unused proteins in the liver is brought into organ P through blood by an artery R. The numerous tiny filters S present in organ P clean the dirty blood by removing the waste product Q. The clean blood goes into circulation through a vein T. The waste substance Q other waste salts, and excess water form a yellowish liquid U which goes from organ P into a bag-like structure V
through two tubes W. This liquid is then thrown out of the body through a tube X.
(a) What is (i) organ P, and (ii) waste substance Q ?
(b) Name (i) artery R; and (ii) vein T.
(c) What are tiny filters S known as?
(d) Name (i) liquid U (ii) structure V (iii) tubes W, and (iv) tube X.

Answer

→ (a) (i) Kidneys (P) (ii) Urea (Q)
(b) (i) Renal artery (R) (ii) Renal vein (T)
(c) Nephrons (S)
(d) (i) Urine (U) (ii) Bladder (V) (iii) Ureters (W) (iv)Urethra (X)

101. The organs A of a person have been damaged completely due to which too much of a poisonous waste material B has started accumulating in his blood, making it dirty. In order to save this person's life, the blood from an artery in the person's arm is made to flow into long tubes made of substance E which are
kept in coiled form in a tank containing solution F. This solution contains three materials G, H and I in similar proportions to those in normal blood. As the person's blood passes through long tubes of substance E, most of the wastes present in it go into solution. The clean blood is then put back into a vein in the arm of the person for circulation.
(a) What are organs A ?
(b) Name the waste substance B.
(c) What are (i) E, and (ii) F ?
(d) Name G, H and I.
(e) What is the process described above known as?

Answer

→ (a) Organs A is Kidney.
(b) Waste substance (B) is urea.
(c) (i) Cellulose (E)
(ii) Dialysing solution (F)
(d) Water (G), Glucose (H) and Salts (I)
(e) Dialysis

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