1.What is the role of glomerulus in kidney?
Ans.Glomerulus is a group of capillaries present in the cup like Bowman’s Capsule. It receives blood from renal artery which brings excre tory wastes from body to the kidney. It filters water, salts, glucose, urea, the nitrogen containing end products of proteins and yellow bile compounds from the liver.
2.Why is it esse ntial to match the blood groups of donors and recei ver person before arranging transfusion of blood?
Ans.RBC’s of blood carries antigen as well as antib ody. If blood is not matched before transfusion then blood of receiver start producing antibodies against donor blood and destroys blood cells, this causes deficiency of blo od and causes death.
3.Why is it necessary to separate oxygenated & deoxyg enated blood in mammals & birds?
Ans.Separation of oxygenated and deoxygenated bloo d allows good supply of oxygen to the body. This system is useful in animals that ha ve high energy requirement Mammals and birds constantly need oxygen to get ene rgy to maintain constant body temperature
4.. Da rk reaction of photosynthesis does not need light. Do plants undergo dark reaction at night explain.
Ans.Dark reaction does not mean that it occurs in the absence of light i.e., at night. Infact these reactions do not depend on light energy and o ccur simultaneously with light reaction.
5.. Differentiate inhalation and exhalation.
Ans.
6.What are the functions of human respiratory system ?
Ans.i) Gaseous exchange for the cellular respir atory process.
(ii) Sound production by vocal cords
(iii) Abdominal compression which helps in urinati on, passing of faeces and childbirth.
(iv) Laughing and sneezing for self-cleaning the r espiratory surface.
7.Discuss the mecha nism of respiration in human beings.
Ans.Mechanism of Respiration – It occurs in follow ing steps
a) Breathing – Taking in oxygen and expelling car bon – dioxide out is called
breathing. It involves following steps –
(i) Inhalation – It is taking in oxygen. It occurs due to contraction of muscles attached to ribs. This lifts ribs and flatter diaph ragm, which increase the volume of thoracic cavity. Hence the pressure insid e the thoracic cavity decreases and air rushes inside of the lungs. (ii) Exhalation – It is expelling of carbon – dio xide. It occurs due to relaxation of muscles attached to ribs and diaphragm is done shap ed. This decreases the volume of thoracic cavity and decreases air pressur e and expels CO 2 out of the lung.
b) Exchange of gases – It takes place between th e alveoli of lungs and surrounding blood capillaries .
c) Transport of gases in blood – Hemoglobin pre sent in the blood transport. O 2 and CO 2 in blood. Oxygen is transport from the lungs to th e body cells in the form of any hemoglobin.
d) Oxidation of food – Break down of glucose mole cules which produce energy. It occurs is into chondria.
8.W hat is glycolysis?
Ans.Breakdown of Glucose into pyruvate is known as glycolysis.
9.Name the largest artery of body.
Ans.Aorta
10.Why the walls of trachea are supported by cartilaginous rings?
Ans.The trachea is supported by cartilaginous ring s which prevent the collapsing even when there is not much air in it.
11.What are the r aw materials for photosynthesis?
Ans.Raw materials for photosynthesis are –
a) Carbon – dioxide
b) Water
c) Chlorophyll and Sunlight
12.What is the role of diaphragm during inhalation and exhala tion?
Ans.Diaphragm changes its shape during inhalation a nd exhalation and increases and decreases volume of thoracic cavity respectively. T his causes entry and expel of air from lungs.
13.What is the advantage of four chambered of h ea r t?
Ans.The right and left parts are separated by a sep tum to prevent oxygenated and deoxygenated blood from mixing. This fulfills the c onstant use of energy to maintain their body temperature. Their energy needs are high , which are fulfilled efficiently because of non – mixing of oxygenated & deoxygenate d blood.
14.What is role of skin, lungs and intestine in the pr oce ss of excretion in man?
Ans. Skin – Skin excrete excess salts and water in the form of sweat.
Lungs – Lungs expel carbon – dioxide during exhala tion.
Intestine – Intestine throw out undigested food in the form of faeces through anus
15.Why and how does water enter continuously int o the root xylem of plants?
Ans. Xylem transports water and minerals to the pla nt body. The roots of a plant have hair called root hairs. The root hairs are directly in c ontact with the film of water in between the soil particles. Water and minerals get into the root hair by the process of diffusion.
The water and minerals absorbed by the root hair fo rm the soil pass from cell to cell by osmosis through the epidermis root cortex, endoderm is and reaches the root xylem. The xylem vessels of the root the plant are connected t o the xylem vessels into stem.
Therefore the water containing dissolved minerals enter the root xylem vessels into stem xylem vessels. The xylem vessels of the stem b ranch into the leaves of the plants.
So the water & minerals carried by the xylem vessel s in the stem reach the leaves through the branched xylem vessels which enter from the petiole into the each part of the leaf. Thus the water and minerals form the soil reach through the root and stem to the leaves of the plants.
Evaporation of water molecules from the cells of a leaf creates a suction which pulls water form the xylem cells of roots. The loss of wa ter in the form of vapour from the aerial parts of the plants is known as transpiratio n.
16.What is the role of following in human digestive sy stem –
a) mucous
b) Bile Juice
c) Trypsin
Ans. a) Mucus – It protects the inner living of s tomach from HCl.
b) Bile Juice – It makes the acidic food alkali ne so that pancreatic enzymes act on it.
c) Trypsin – It digest proteins into amino acids.
17.Describe an experiment to prove that carbon – dioxide is essential for the process of photosynthesis.
Ans. Experiment showing Co 2 is essential for photosynthesis.
1) Take a potted plant with elongated leaves
2) Take an empty bottle and put a little amount of potassium hydroxide (KOH) in it.
3) Now cut the cork of the bottle into two pa rts and place it on one of the leaves of the potted plant in between the two parts of the cork.
4) Now put the bottle in the presence of sunligh t 72 – 96 hours.
5) Now test the leaf for the presence of starch.
18.Name the red pigment carrying oxygen in blood. - Ans.Haemoglobin
19.Name the hormon e which is responsible for reabsorption of water in nephrons.
Ans.Anti – diuretic – hormone (ADH) or vasopressin
20.How is opening and closing of stomata regulated?
Ans.The closing and openings of the stomata is reg ulated by guard cells. When the guard cells swell or turgid due to entry of water, the st omata are opened. The guard cells shrink due to loss of water, the stomata get closed .
21.State two vital functions of kidney.
Ans.Function of kidney are –
1) It maintains water balance in the body tissues .
2) It controls calcium levels in the blood to mai ntain healthy bones.
22.Differentiate between aerobic and anaerobic respiration.
Ans. Aerobic Respiration:
a.It occurs in the presence of oxygen
b.It occurs in cytoplasm and in mitochondria
c.End products are CO2 and H2O
d.There is complete breakdown of glucose
e.Large amount of energy is released
Anaerobic Respiration
a.It occurs in the absence of oxygen
b.It occurs in cytoplasm
c.incomplete breakdown of glucose
d.end products are CO2 and ethanol or lactic acid
e.Little energy is released as compared to aerobic respiration
23.Meat is ea s ier to digest as compared to grass. Why?
Ans.It is easier to digest meat because our di gestive juices contain enzymes which can easily digest meat but our body does not digest cel lulose which is a main component of grass.
24.Discuss the mode of nutrition in amoeba.
Ans.Steps of Nutrition in amoeba –
a) Formation of pseudopodia – When Amoeba comes in contact with a food particle, it forms pseudopodia which envelops food particles.
b) Ingestion – The tips of pseudopodia fuse with each other, together with variable amount of food particles and water, forms food vacuole, this process is known as ingestion.
c) Digestion – The vacuoles are surrounded by l ysosomes which fuses with vacuole and digest the food particles present in va cuole.
d) Exocytosis – The soluble products of digestio n are passed out into due cytoplasm from the food vacuole. And the remaining undigested materials are passed out of the body with the help of a process called exocytosis.
25.With the help of labeled diagram, discuss the structure of cross – section of leaf.
Ans.Leaf has two parts :-
(i) Epidermis – Outermost layer of cell is called epidermis. Lower epidermis has small pores in between cells called stomata.
(ii) Mesophyll – Parenchymatons cells containing chloroplast is called mesophyll. It is two types – palisade and spongy parenchyma.
26.What do you m e an by ‘lymph’. Mention its function.
Ans.Lungs have some adaptations in them so that ef ficient exchanges of gases take place.
The adaptations are –
a) Increased surface area
b) Very fine and delicate surface for easy exchan ge of oxygen and carbon dioxide
c) Mechanism for moving the air in and out of res piratory surface where the oxygen is absorbed.
27.How are lungs designed in human beings to maximize the area of ex change of gases
Ans.Lungs have some adaptations in them so that ef ficient exchanges of gases take place. The adaptations are –
a) Increased surface area
b) Very fine and delicate surface for easy exchan ge of oxygen and carbon dioxide
c) Mechanism for moving the air in and out of res piratory surface where the oxygen is absorbed.
28. Describe the role of following in digestion. a) Bile
b) Salivary amylase
c) HCl
Ans. a) Bile – emulsification of fats
b) Salivary amylase – digest starch in mouth
c) HCl – Activate pepsinogen by making medium acidic in stomata.
29.Name excretory organ in amoeba and earthworm
Ans.Amoeba – Cell membrane
Earthworm – Outer covering (skin)
30.Name the plant tissue through which water and miner als are transported in plants
Ans.Xylem and Phloem
31.What are the two stages in photo synthesis?
Ans.Two stages in photosynthesis –
a) Light reaction – Light energy break s up water molecular into hydrogen and oxygen, called photolysis of water
b) Dark reaction – Fixation and conversion of carbon – dioxide (CO 2 ) into a simple carbohydrates, glucose.
32.What is the difference between arteries & veins?
Ans.Arteries
a.It carries blood away from the heart
b.They are thick walled
c.They have narrow lumen
d.Pressure is high
Veins
a.It carried blood toward the heart
b.They are thin walled
c.They have wide lumen
d.Pressure is low
33.What is villi? What are its functions?
Ans.Finger like projection present in the inner li ning of small intestine are called villi. They increase the surface area for the absorption o f digested food in the small intestine.
34.What type of respiration takes place in human muscl es during vigorous exercise and why?
Ans.During vigorous exercise, anaerobic respiratio n takes place in human muscles. During exercise our energy requirement increase, so our striated muscles start respiring anaerobically in the lack of oxygen and p roducers ATP molecules.
35.What is “translocation”? Why it is essential for plants.
Ans. Transportation of organic solutes in the plants is called translocation. It is necessary, because all the cells need food to carry out their vital functions. It occurs in upward as well as downward direction or to the storage org ans of roots, fruits, seeds and to growing organs.
36.How respiration does takes place in p lants?
Ans.here are three modes for the exchange of gase s in plants
a) Some small plants can carry out gaseous excha nge by simple diffusion over their whole surfaces.
b) Large flowering plants exchange gases through stomata on their leaves and green stem.
c) In woody stems, exchange occurs through cracks in the bark or lenticels.
37.How is transpiration pull responsible for upward mo vement of water?
Ans.The leaves lose water in the form of water va pours through stomata by a process known as transpiration. Continuous transpiration cr eates a s suction in the water column of the xylem elements and it reaches upto th e roots. This pull is called transpiration pull. Due to transpiration, the water column of the plant is pulled up from below to the top of the plant.
38.Discuss the major steps involved in process of nutr ition in human beings.
Ans. Major steps involved in human nutrition are –
a) Ingestion – Intake of food through mouth. Humans have holozoic mode of nutrition. They engulf solid particles.
b) Digestion – The break down complex food m aterial into simpler one in alimentary canal with the help of mechanical as wel l as chemical process.
c) Absorption – Digested food is absorbed by the small finger like projections, villi present in the small intestine.
d) Assimilation – Absorbed food reaches to al l cells via blood, and utilized for energy, growth and development.
e) Excretion – Undigested food from small int estine passed into large intestine, and then it is thrown out by Anus.
39.With the help of a label l ed diagram of human excretory system, Mention its important part and explain them.
Ans.1) Kidney – It is the functional unit of exc retory system. Each kidney is made up of about million microscopic coiled channels called ne phrons. Nephrons are the basic filtration unit in the kidneys. It consists o f – Glomerulus’s, Bowman’s capsule, convoluted tubule.
2) Ureter – Wastes comes out of the kidney into the ureter.
3) Urinary bladder – Ureter pours its contents into a muscular sac called the urinary bladder.
4) Urethra – Urine flows from bladder to the ou tside through the urethra.
40 . Where does digestion of starch begin in human body?
Ans.Mouth
41.Give one example each of saprophytic and parasitic nutrition.
Ans.Parasitic Nutrition – Plasmodium (Protozoa)
Saprophytic Nutrition – fungi
42.What is common for cuscuta, ticks and leeches?
Ans.Parasitic Nutrition – Plasmodium (Protozoa)
Saprophytic Nutrition – fungi
43.What advantage over an aquatic organism does a terr estrial organism have with regard to obtaining oxygen for respiration?
Ans.Parasitic Nutrition – Plasmodium (Protozoa)
Saprophytic Nutrition – fungi
44.Differentiate between single and double circulation found in vertebrates.
Ans.
45.Name th e substrates for the following enzymes
a) trypsin b) amylase
c) pepsin d) lipase
Ans.a) Protein b) Starch c) Protein d) Lipids .
46.What are the functions of lymph in our body?
Ans.Functions of lymph are-
a) It returns tissue fluid from interstitial space into the blood.
b) It collects carbon dioxide, waste products and metabolites from tissues via tissue fluid.
c) Lymph has lymphocytes (WBC’S), the lymph p rovides in immunity to the body and fight against the invading organisms.
47.How is h a emoglobin associated with respiration explained?
Ans.Transportation of oxygen and carbon – dioxide occurs with the help of respiratory pigment haemoglobin. Haemoglobin is a red pigment h aving very high affinity for oxygen. Oxygen is transported from the lungs to the body cells in the form of oxyhemoglobin. Carbon – dioxide is transported from the body cells to the lungs in the form of carbamino – haemoglobin
48.What are the modes of excretion in plants?
Ans.Modes of excretion in plants are –
a) The plants get rid of excess water by transpir ation.
b) The only major gases excretory product o f plants in oxygen. It is released from plants into the environment by diffusion.
c) Organic wastes of plants are stored within dea d permanent tissues such as wood or within leaves or bark which are periodicall y removed.
d) The plants also excrete some wastes substances into the soil around them.
e) Many wastes products of plants are stored in c ellular vacuoles.
49.Give an experiment to prove the essentiality of lig ht for photosynthesis
Ans.a) Destarched the plant by leaving it in dart for 48 – 72 hours.
b) Now place strips of black paper or metal foil over destarched leaves and expose them to light for several hours.
50.
Describe the process of urine formation in kidneys. Ans.Glomerulus is a group of capillaries present in the cup like Bowman’s Capsule. It receives blood from renal artery which brings excre tory wastes from body to the kidney. It filters water, salts, glucose, urea, the nitrogen containing end products of proteins and yellow bile compounds from the liver.
2.Why is it esse ntial to match the blood groups of donors and recei ver person before arranging transfusion of blood?
Ans.RBC’s of blood carries antigen as well as antib ody. If blood is not matched before transfusion then blood of receiver start producing antibodies against donor blood and destroys blood cells, this causes deficiency of blo od and causes death.
3.Why is it necessary to separate oxygenated & deoxyg enated blood in mammals & birds?
Ans.Separation of oxygenated and deoxygenated bloo d allows good supply of oxygen to the body. This system is useful in animals that ha ve high energy requirement Mammals and birds constantly need oxygen to get ene rgy to maintain constant body temperature
4.. Da rk reaction of photosynthesis does not need light. Do plants undergo dark reaction at night explain.
Ans.Dark reaction does not mean that it occurs in the absence of light i.e., at night. Infact these reactions do not depend on light energy and o ccur simultaneously with light reaction.
5.. Differentiate inhalation and exhalation.
Ans.
6.What are the functions of human respiratory system ?
Ans.i) Gaseous exchange for the cellular respir atory process.
(ii) Sound production by vocal cords
(iii) Abdominal compression which helps in urinati on, passing of faeces and childbirth.
(iv) Laughing and sneezing for self-cleaning the r espiratory surface.
7.Discuss the mecha nism of respiration in human beings.
Ans.Mechanism of Respiration – It occurs in follow ing steps
a) Breathing – Taking in oxygen and expelling car bon – dioxide out is called
breathing. It involves following steps –
(i) Inhalation – It is taking in oxygen. It occurs due to contraction of muscles attached to ribs. This lifts ribs and flatter diaph ragm, which increase the volume of thoracic cavity. Hence the pressure insid e the thoracic cavity decreases and air rushes inside of the lungs. (ii) Exhalation – It is expelling of carbon – dio xide. It occurs due to relaxation of muscles attached to ribs and diaphragm is done shap ed. This decreases the volume of thoracic cavity and decreases air pressur e and expels CO 2 out of the lung.
b) Exchange of gases – It takes place between th e alveoli of lungs and surrounding blood capillaries .
c) Transport of gases in blood – Hemoglobin pre sent in the blood transport. O 2 and CO 2 in blood. Oxygen is transport from the lungs to th e body cells in the form of any hemoglobin.
d) Oxidation of food – Break down of glucose mole cules which produce energy. It occurs is into chondria.
8.W hat is glycolysis?
Ans.Breakdown of Glucose into pyruvate is known as glycolysis.
9.Name the largest artery of body.
Ans.Aorta
10.Why the walls of trachea are supported by cartilaginous rings?
Ans.The trachea is supported by cartilaginous ring s which prevent the collapsing even when there is not much air in it.
11.What are the r aw materials for photosynthesis?
Ans.Raw materials for photosynthesis are –
a) Carbon – dioxide
b) Water
c) Chlorophyll and Sunlight
12.What is the role of diaphragm during inhalation and exhala tion?
Ans.Diaphragm changes its shape during inhalation a nd exhalation and increases and decreases volume of thoracic cavity respectively. T his causes entry and expel of air from lungs.
13.What is the advantage of four chambered of h ea r t?
Ans.The right and left parts are separated by a sep tum to prevent oxygenated and deoxygenated blood from mixing. This fulfills the c onstant use of energy to maintain their body temperature. Their energy needs are high , which are fulfilled efficiently because of non – mixing of oxygenated & deoxygenate d blood.
14.What is role of skin, lungs and intestine in the pr oce ss of excretion in man?
Ans. Skin – Skin excrete excess salts and water in the form of sweat.
Lungs – Lungs expel carbon – dioxide during exhala tion.
Intestine – Intestine throw out undigested food in the form of faeces through anus
15.Why and how does water enter continuously int o the root xylem of plants?
Ans. Xylem transports water and minerals to the pla nt body. The roots of a plant have hair called root hairs. The root hairs are directly in c ontact with the film of water in between the soil particles. Water and minerals get into the root hair by the process of diffusion.
The water and minerals absorbed by the root hair fo rm the soil pass from cell to cell by osmosis through the epidermis root cortex, endoderm is and reaches the root xylem. The xylem vessels of the root the plant are connected t o the xylem vessels into stem.
Therefore the water containing dissolved minerals enter the root xylem vessels into stem xylem vessels. The xylem vessels of the stem b ranch into the leaves of the plants.
So the water & minerals carried by the xylem vessel s in the stem reach the leaves through the branched xylem vessels which enter from the petiole into the each part of the leaf. Thus the water and minerals form the soil reach through the root and stem to the leaves of the plants.
Evaporation of water molecules from the cells of a leaf creates a suction which pulls water form the xylem cells of roots. The loss of wa ter in the form of vapour from the aerial parts of the plants is known as transpiratio n.
16.What is the role of following in human digestive sy stem –
a) mucous
b) Bile Juice
c) Trypsin
Ans. a) Mucus – It protects the inner living of s tomach from HCl.
b) Bile Juice – It makes the acidic food alkali ne so that pancreatic enzymes act on it.
c) Trypsin – It digest proteins into amino acids.
17.Describe an experiment to prove that carbon – dioxide is essential for the process of photosynthesis.
Ans. Experiment showing Co 2 is essential for photosynthesis.
1) Take a potted plant with elongated leaves
2) Take an empty bottle and put a little amount of potassium hydroxide (KOH) in it.
3) Now cut the cork of the bottle into two pa rts and place it on one of the leaves of the potted plant in between the two parts of the cork.
4) Now put the bottle in the presence of sunligh t 72 – 96 hours.
5) Now test the leaf for the presence of starch.
18.Name the red pigment carrying oxygen in blood. - Ans.Haemoglobin
19.Name the hormon e which is responsible for reabsorption of water in nephrons.
Ans.Anti – diuretic – hormone (ADH) or vasopressin
20.How is opening and closing of stomata regulated?
Ans.The closing and openings of the stomata is reg ulated by guard cells. When the guard cells swell or turgid due to entry of water, the st omata are opened. The guard cells shrink due to loss of water, the stomata get closed .
21.State two vital functions of kidney.
Ans.Function of kidney are –
1) It maintains water balance in the body tissues .
2) It controls calcium levels in the blood to mai ntain healthy bones.
22.Differentiate between aerobic and anaerobic respiration.
Ans. Aerobic Respiration:
a.It occurs in the presence of oxygen
b.It occurs in cytoplasm and in mitochondria
c.End products are CO2 and H2O
d.There is complete breakdown of glucose
e.Large amount of energy is released
Anaerobic Respiration
a.It occurs in the absence of oxygen
b.It occurs in cytoplasm
c.incomplete breakdown of glucose
d.end products are CO2 and ethanol or lactic acid
e.Little energy is released as compared to aerobic respiration
23.Meat is ea s ier to digest as compared to grass. Why?
Ans.It is easier to digest meat because our di gestive juices contain enzymes which can easily digest meat but our body does not digest cel lulose which is a main component of grass.
24.Discuss the mode of nutrition in amoeba.
Ans.Steps of Nutrition in amoeba –
a) Formation of pseudopodia – When Amoeba comes in contact with a food particle, it forms pseudopodia which envelops food particles.
b) Ingestion – The tips of pseudopodia fuse with each other, together with variable amount of food particles and water, forms food vacuole, this process is known as ingestion.
c) Digestion – The vacuoles are surrounded by l ysosomes which fuses with vacuole and digest the food particles present in va cuole.
d) Exocytosis – The soluble products of digestio n are passed out into due cytoplasm from the food vacuole. And the remaining undigested materials are passed out of the body with the help of a process called exocytosis.
25.With the help of labeled diagram, discuss the structure of cross – section of leaf.
Ans.Leaf has two parts :-
(i) Epidermis – Outermost layer of cell is called epidermis. Lower epidermis has small pores in between cells called stomata.
(ii) Mesophyll – Parenchymatons cells containing chloroplast is called mesophyll. It is two types – palisade and spongy parenchyma.
26.What do you m e an by ‘lymph’. Mention its function.
Ans.Lungs have some adaptations in them so that ef ficient exchanges of gases take place.
The adaptations are –
a) Increased surface area
b) Very fine and delicate surface for easy exchan ge of oxygen and carbon dioxide
c) Mechanism for moving the air in and out of res piratory surface where the oxygen is absorbed.
27.How are lungs designed in human beings to maximize the area of ex change of gases
Ans.Lungs have some adaptations in them so that ef ficient exchanges of gases take place. The adaptations are –
a) Increased surface area
b) Very fine and delicate surface for easy exchan ge of oxygen and carbon dioxide
c) Mechanism for moving the air in and out of res piratory surface where the oxygen is absorbed.
28. Describe the role of following in digestion. a) Bile
b) Salivary amylase
c) HCl
Ans. a) Bile – emulsification of fats
b) Salivary amylase – digest starch in mouth
c) HCl – Activate pepsinogen by making medium acidic in stomata.
29.Name excretory organ in amoeba and earthworm
Ans.Amoeba – Cell membrane
Earthworm – Outer covering (skin)
30.Name the plant tissue through which water and miner als are transported in plants
Ans.Xylem and Phloem
31.What are the two stages in photo synthesis?
Ans.Two stages in photosynthesis –
a) Light reaction – Light energy break s up water molecular into hydrogen and oxygen, called photolysis of water
b) Dark reaction – Fixation and conversion of carbon – dioxide (CO 2 ) into a simple carbohydrates, glucose.
32.What is the difference between arteries & veins?
Ans.Arteries
a.It carries blood away from the heart
b.They are thick walled
c.They have narrow lumen
d.Pressure is high
Veins
a.It carried blood toward the heart
b.They are thin walled
c.They have wide lumen
d.Pressure is low
33.What is villi? What are its functions?
Ans.Finger like projection present in the inner li ning of small intestine are called villi. They increase the surface area for the absorption o f digested food in the small intestine.
34.What type of respiration takes place in human muscl es during vigorous exercise and why?
Ans.During vigorous exercise, anaerobic respiratio n takes place in human muscles. During exercise our energy requirement increase, so our striated muscles start respiring anaerobically in the lack of oxygen and p roducers ATP molecules.
35.What is “translocation”? Why it is essential for plants.
Ans. Transportation of organic solutes in the plants is called translocation. It is necessary, because all the cells need food to carry out their vital functions. It occurs in upward as well as downward direction or to the storage org ans of roots, fruits, seeds and to growing organs.
36.How respiration does takes place in p lants?
Ans.here are three modes for the exchange of gase s in plants
a) Some small plants can carry out gaseous excha nge by simple diffusion over their whole surfaces.
b) Large flowering plants exchange gases through stomata on their leaves and green stem.
c) In woody stems, exchange occurs through cracks in the bark or lenticels.
37.How is transpiration pull responsible for upward mo vement of water?
Ans.The leaves lose water in the form of water va pours through stomata by a process known as transpiration. Continuous transpiration cr eates a s suction in the water column of the xylem elements and it reaches upto th e roots. This pull is called transpiration pull. Due to transpiration, the water column of the plant is pulled up from below to the top of the plant.
38.Discuss the major steps involved in process of nutr ition in human beings.
Ans. Major steps involved in human nutrition are –
a) Ingestion – Intake of food through mouth. Humans have holozoic mode of nutrition. They engulf solid particles.
b) Digestion – The break down complex food m aterial into simpler one in alimentary canal with the help of mechanical as wel l as chemical process.
c) Absorption – Digested food is absorbed by the small finger like projections, villi present in the small intestine.
d) Assimilation – Absorbed food reaches to al l cells via blood, and utilized for energy, growth and development.
e) Excretion – Undigested food from small int estine passed into large intestine, and then it is thrown out by Anus.
39.With the help of a label l ed diagram of human excretory system, Mention its important part and explain them.
Ans.1) Kidney – It is the functional unit of exc retory system. Each kidney is made up of about million microscopic coiled channels called ne phrons. Nephrons are the basic filtration unit in the kidneys. It consists o f – Glomerulus’s, Bowman’s capsule, convoluted tubule.
2) Ureter – Wastes comes out of the kidney into the ureter.
3) Urinary bladder – Ureter pours its contents into a muscular sac called the urinary bladder.
4) Urethra – Urine flows from bladder to the ou tside through the urethra.
40 . Where does digestion of starch begin in human body?
Ans.Mouth
41.Give one example each of saprophytic and parasitic nutrition.
Ans.Parasitic Nutrition – Plasmodium (Protozoa)
Saprophytic Nutrition – fungi
42.What is common for cuscuta, ticks and leeches?
Ans.Parasitic Nutrition – Plasmodium (Protozoa)
Saprophytic Nutrition – fungi
43.What advantage over an aquatic organism does a terr estrial organism have with regard to obtaining oxygen for respiration?
Ans.Parasitic Nutrition – Plasmodium (Protozoa)
Saprophytic Nutrition – fungi
44.Differentiate between single and double circulation found in vertebrates.
Ans.
45.Name th e substrates for the following enzymes
a) trypsin b) amylase
c) pepsin d) lipase
Ans.a) Protein b) Starch c) Protein d) Lipids .
46.What are the functions of lymph in our body?
Ans.Functions of lymph are-
a) It returns tissue fluid from interstitial space into the blood.
b) It collects carbon dioxide, waste products and metabolites from tissues via tissue fluid.
c) Lymph has lymphocytes (WBC’S), the lymph p rovides in immunity to the body and fight against the invading organisms.
47.How is h a emoglobin associated with respiration explained?
Ans.Transportation of oxygen and carbon – dioxide occurs with the help of respiratory pigment haemoglobin. Haemoglobin is a red pigment h aving very high affinity for oxygen. Oxygen is transported from the lungs to the body cells in the form of oxyhemoglobin. Carbon – dioxide is transported from the body cells to the lungs in the form of carbamino – haemoglobin
48.What are the modes of excretion in plants?
Ans.Modes of excretion in plants are –
a) The plants get rid of excess water by transpir ation.
b) The only major gases excretory product o f plants in oxygen. It is released from plants into the environment by diffusion.
c) Organic wastes of plants are stored within dea d permanent tissues such as wood or within leaves or bark which are periodicall y removed.
d) The plants also excrete some wastes substances into the soil around them.
e) Many wastes products of plants are stored in c ellular vacuoles.
49.Give an experiment to prove the essentiality of lig ht for photosynthesis
Ans.a) Destarched the plant by leaving it in dart for 48 – 72 hours.
b) Now place strips of black paper or metal foil over destarched leaves and expose them to light for several hours.
50.
Ans. The functional unit of kidney is called nephron. A nephron is composed of a tuft of blood capillaries and h ighly coiled ducts. The tuft of blood capillaries is surrounded by a cup-shaped struct ure; called Bowman’s capsule.
• Waste material from blood are filtered out of the capil laries and they go through the wall of Bowman’s capsule.
• After that, the waste material and water pass throug h the ducts. When the mixture of water and other materials move through the duct, some m aterials and water are reabsorbed. This depends on excess amount of water pres ent in the body.
• After reabsorption of water and other material, urine b ecomes concentrated. This then goes to the collecting duct.
• Urine from collecting ducts moves through ureter into th e urinary bladder. From the urinary bladder, urine is expelled from the body as a nd when required.
No comments:
Post a Comment