Life Processes Class-10 Biology 2 Marks Previous Year Questions
Q.1) What is the function of diaphragm in human respiratory system ? Where is it present in human body?
• The main function of the diaphragm is to flatten during inhalation, which expands the chest cavity and draws the air into the lungs / helps in breathing.
• It is located at the base of chest cavity.
Q.2) (a) Why is bile juice considered to be very important for digestion, even though it does not contain any digestive enzymes?
(b) Name some substances present in the initial filtrate and subsequently selectively reabsorbed in the tubules of nephron.
(a) • Bile emulsifies fats for their digestion.
• It makes medium alkaline for further digestion by pancreatic and small intestinal enzymes.
(b) Glucose, water, salt, amino acid
Q.3) (a) Why is bile juice considered to be very important for digestion, even though it does not contain any digestive enzymes?
(b) Name some substances present in the initial filtrate and subsequently selectively reabsorbed in the tubules of nephron.
(a) • Bile emulsifies fats for their digestion.
• It makes medium alkaline for further digestion by pancreatic and small intestinal enzymes.
(b) Glucose, water, salt, amino acid
Q.4) Briefly mention the steps in double-circulation through human heart.
• Oxygenated blood from lungs comes to left atrium which pushes it to left ventricle →
• Left ventricle contracts to push blood into aorta, to be sent to body parts →
• Deoxygenated blood from body parts is collected and sent to right atrium →
• Right atrium pushes it to right ventricle, to be sent to lungs for oxygenation.
Q.5) Varun is diabetic. His latest ultrasound reports showed a blockage in his pancreatic duct. How will this affect the dual functioning of the pancreas?
• As his pancreatic duct is blocked, enzymes for digestion will not be transported to small intestine / The blockage will cause difficulty in digestion of proteins, carbohydrates and fats.
• Insulin secretion is already affected.
Q.6) Give a diagrammatic representation of nutrition in Amoeba.
Q.7) “Transpiration in plants is a necessary evil.”
Comment on the statement giving two reasons.
• Necessary- It helps in transport of water and minerals from roots to leaves/ helps in temperature regulation.
• Evil- It results in loss of water.
Q.8) The leaves of a plant first prepares food ‘P’ by photo-synthesis. Food ‘P’ is then converted to food ‘Q’, which is stored in the leaves if not used immediately. What are ‘P’ and ‘Q’ ? What are the raw materials and conditions required for synthesis of ‘P’ ?
• Food:
▪ P – Glucose
▪ Q – Starch
• Raw materials: CO2, H2O
• Conditions: Presence of sunlight, chlorophyll
Q.9) Given below is a diagrammatic representation of cross-section of a leaf : 
(i) Identify ‘P’ in the given diagram and write down its role in plants.
(ii) Write down a balanced equation of process of photosynthesis.
(i) • P – Chloroplasts
• Absorb light energy and helps in photosynthesis.
(ii)
Q.10) Separation of right side and left side of the heart is useful to keep oxygenated and deoxygenated blood from mixing. Various organisms have different types of heart.
(I) Fill in the blanks (i) to (iii) correctly according to the type of organisms and their evolution in terms of blood circulation :
(II) Which type of circulation is most efficient ?
I. (i) 2-chambered
(ii) Amphibians/Reptiles
(iii) Double circulation
II. Double circulation
Q.11) What kind of respiration provides more energy and why ?
• Aerobic Respiration
• Complete breakdown of glucose takes place in presence of oxygen releasing more energy.
Q.1) How is lymph formed ? State its important function.
•Through the pores present in the walls of capillaries some amount of plasma, proteins and blood cells escape into intercellular spaces in the tissue to form the tissue fluid called lymph.
•Lymph carries digested and absorbed fat from intestine/ drains excess fluid from extracellular space back into the blood.
Q.2) (a) Identify ‘X’ in the figure of human nephron shown below. What role does it play in the process of urine formation ?
(b) Why some substances are selectively reabsorbed from the initial filtrate of urine, as it flows along the tabular part of nephron ?
(a) X- Bowman’s capsule; Function: collects the filtrate
(b) It is because the nephron monitors how much excess water is there in the body and how much dissolved waste is to be removed or how much useful substances are retained by the body.
Q.3) “In human alimentary canal the small intestine is digested to absorb the digested food.” Justify this statement.
The inner lining of the small intestine has numerous finger-like projections called villi, which increases the surface area for absorption of digested food; The villi are richly supplied with blood vessels; which transport the absorbed food to each and every cell of the body.
Q.4) “Plants use a variety of techniques to get rid of waste materials.” Justify this statement giving any four ways.
Four ways:
1. O2 as a waste product through stomata.
2. Excess water by transpiration.
3. Shedding of leaves.
4. Stored as resins and gums in old xylem.
5. Into the soil
6. Stored in cellular vacuoles (Any four)
Q.5) State the main function of arteries. Why do they have thick and elastic walls ?
• To carry oxygenated blood away from the heart to various organs of the body.
• Because blood flows in Arteries under high pressure.
Q.6) State the main function of veins in human circulatory system. Why do they not need thick walls ?
• Veins carry deoxygenated blood from different organs and bring it back to the heart.
• Because blood flows at low pressure inside veins.
Q.7) (i) The transport system in plants is relatively slower than in animals. Give reasons.
(ii) State the role of phloem in the transport of materials in plants.
(i) Plants have low energy needs because they have a large proportion of dead cells in many tissues / Plants have low energy needs as they do not move
(ii) Translocation of soluble products of photosynthesis from leaves to other parts of the plant / It transports amino acids and other substances to storage organs of roots, fruits and seeds and to growing organs.
Q.8) Besides minimising the loss of blood, why is it essential to plug any leak in a blood vessel ? Name the component of blood which helps in this process and state how this component perform this function.
• Plugging of the leak in blood vessels prevents lowering of the blood pressure / maintains the efficiency of the pumping system.
• Platelets
• Help to clot the blood at the site of injury.
Q.9) Give reasons :
(a) During a breathing cycle, the lungs always contain a residual volume of air.
(b) As compared to oxygen, carbon dioxide is mostly transported in dissolved form in our blood.
(a) So that there is sufficient time for oxygen to be absorbed and for the carbon dioxide to be released.
(b) Carbon dioxide is more soluble in water than oxygen is, hence is mostly transported in dissolved form in our blood.
Q.10) How is the small intestine in humans designed to absorb the digested food ?
The inner lining of the small intestine has numerous finger - like projections called villi which are thin walled and richly supplied with blood,they increase the surface area for absorption of digested food.
Q.11) Explain how circulation of blood takes place in fishes.
Fish have two chambered heart, and the blood pumped to the gills, is oxygenated , and passes directly to the rest of the body. Blood goes only once through the heart to complete one cycle.
Q.1) Sometimes while running, the athletes suffer from muscle cramps. Why ? How is the respiration in this case different from aerobic respiration ?
• Formation of lactic acid in muscles causes cramps.
• Aerobic respiration takes place in the presence of oxygen whereas the respiration taking place above is due to lack of oxygen. / End products of aerobic respiration are CO2 + H2O + Energy whereas in the above case, Lactic acid + Energy is formed.
Q.2) Write the other name given to lymph. State its two functions.
• Tissue fluid / Extracellular fluid Functions : i. Carries digested and absorbed fats from the intestine.
ii. Drains excess fluid from extracellular space back into the blood.
iii. Fight against infections.
(Any two)
Q.3) We need to water the soil in plants on a regular basis. But it ultimately reaches the leaves of the plant. Explain how this takes place.
When water is lost through stomata in the leaves by transpiration, it creates a suction force/transpiration pull. Due to which water is pulled up through xylem of the roots to the leaves.
Q.4) Name the type of nutrition exhibited by Amoeba. Explain how food is taken in and digested by this organism.
• Heterotrophic /Holozoic Nutrition
• Amoeba takes in food using temporary finger-like projections/pseudopodia of the cell which fuse over the food particle forming a food vacuole. Inside the food vacuole complex substances are broken down into simpler substances.
(Diagrammatic explanation is also accepted)
Q.5) Photosynthesis takes place in the leaves and the food prepared by it reaches other parts of the plants. Name the process involved and explain it.
• Translocation
• Transport of soluble products or food prepared by photosynthesis, through phloem in the sieve tubes with the help of companion cells, bot
Q.6) (i) Give reason why herbivorous animals have longer, small intestine than carnivorous animals ?
(ii) Although ‘Pepsin’ and ‘Trypsin’ are both protein digesting enzymes yet they differ from each other. Justify this statement by giving one difference between them.
(i) Herbivores eating grass need a longer small intestine to allow the cellulose to be digested. Meat is easier to digest. Hence carnivores have shorter small intestine.
(ii)
Q.7) Name the blood vessel which brings blood to the kidneys. Why is nephron called a basic filtration unit of kidney ? Write the role of tubular part of nephron in urine formation.
• Renal Artery
• Nephron filters the blood in the kidney / removes nitrogenous wastes/urea/uric acid from it.
• Selective reabsorption of certain substances present in the initial filtrate like glucose, amino acids, salt and water.
Q.8) Mention the pathway of urine in our body starting from the organ of its formation to its excretion. What will happen if the tubular part of the nephron does not work properly?
Kidney → Ureter → Urinary bladder → Urethra
• Reabsorption of nutrients/amino acids, glucose and water will not take place
Q.1) In the process of digestion of food in human beings, two protein-digesting enzymes are secreted. Name the enzymes along with the glands that secrete them.
Gastric gland – Pepsin
Pancreas – Trypsin
Q.2) What is the other name of ‘tissue fluid’ ? Write its two functions.
• Lymph
• Functions:
(i) carries digested and absorbed fat from intestine.
(ii) drains excess fluid from extracellular space back into the blood.
Q.3) Write one specific function each of the following organs in relation with excretion in human beings :
(i) Renal Artery
(ii) Urethra
(iii) Glomerulus
(iv) Tubular part of nephron
(i) Brings the blood containing nitrogenous waste into the kidney.
(ii) Removal of urine / passing out of urine
(iii) Filtration of blood
(iv) Selective reabsorption of useful materials.
Q.4) With the help of a schematic flow chart, show the breakdown of glucose in a cell to provide energy —
(i) in the presence of oxygen
(ii) in lack of oxygen
(i)
(ii)
Q.5) Name the type of blood (oxygenated / deoxygenated) transported by each of the following mentioning the path (i.e. from one organ (which place) to another (which place).
(i) Vena cava
(ii) Pulmonary artery
(i) Vena cava – deoxygenated blood from body to heart.
(ii) Pulmonary artery – deoxygenated blood from heart to lungs
Q.6) (a) Why is it important to prevent oxygenated and deoxygenated blood from mixing in birds and mammals ?
(b) Which animals can tolerate some mixing of the oxygenated and deoxygenated blood streams ? On what factor does the body temperature of these animals depend ?
(a) • Birds and mammals have high energy needs to maintain their body temperature.
(b) • Amphibians / reptiles
• The temperature of the environment.
Q.7) Write one important function each of the following in the human respiratory system :
(a) Rings of Cartilage
(b) Alveoli
(c) Haemoglobin
(d) Lining of mucus
(a) They ensure that the air passage does not collapse / trachea
(b) They provide a surface where exchange of gases take place.
(c) They transport oxygen to tissues .
(d) Inhaled air is filtered
Q.8) List the events in proper sequence that take place during the process of photosynthesis.
(i) Absorption of light energy by chlorophyll.
ii) Conversion of light energy to chemical energy and splitting of water molecules into hydrogen and oxygen.
(iii) Reduction of carbon dioxide to carbohydrates
Q.9) Explain in brief two ways by which leaves of a plant help in excretion.
(i) Excess water is excreted by transpiration.
(ii) Oxygen as waste products of photosynthesis is excreted through stomata.
(iii) Shedding of leaves.
(or any two)
Q.10) Two green plants are kept separately in oxygen free containers, one in the dark and other in sunlight. It was observed that plant kept in dark could not survive longer. Give reason for this observation.
• The plant kept in dark is unable to carry out photosynthesis and due to absence of oxygen it cannot respire.
• But the plant kept in light is able to photosynthesize converting CO2 into oxygen which it can use for respiration.
Q.11) Give two reasons, why bile juice is considered to be an important secretion of liver in the process of digestion ?
• The bile juice makes the food alkaline so that pancreatic enzymes can act on it.
• It breaks down large globules of fat into smaller globules / Emulsification of fat takes place.
Q.12) What will happen if :
(a) Xylem tissue in a plant is removed ?
(b) We are injured and start bleeding ?
(a) Movement of water and minerals from the soil to other parts of the plant will stop and it will ultimately die.
(b) Platelet cells plug these leaks by helping the blood to clot at these points of injury. / Leakage of blood would lead to loss of pressure which would reduce efficiency of pumping system.
Q.13) Write the sequence of events that involve response of a person when a dust particle is inhaled through the nose by him.
Q.14) Name the part of the human excretory system where nephrons are found. Write the structure and function of nephrons.
• Kidneys
• Structure: A cluster of thin-walled capillaries (glomerulus) associated with cup-shaped end of a tube called Bowman’s capsule. This further extends into a tubular part which ends in collective ducts. /
• Function:
Filtration of nitrogenous waste from blood to form urine. / Reabsorption of useful materials from the filtrate. / Osmoregulation (Any one function)
Q.15) Give the name of the enzyme present in the fluid in our mouth cavity. State the gland which produces it. What would happen to the digestion process if this gland stops secreting this enzyme ?
Salivary amylase / Ptyalin – Enzyme.
Salivary gland The breakdown of starch into sugar will not take place.
Q.1) What is placenta ? Why is it extremely essential for the development of embryo ?
• Placenta is a disc like special tissue embedded in the uterine wall.
• The embryo gets nutrition from the mother’s blood with the help of placenta ⁄ It provides large surface area for glucose and oxygen to pass from mother to the embryo ⁄ Removes waste products from embryo into mother’s blood. ( Any one)
Q.2) Mention the changes that occur in the following after fertilisation in a flower : (a) Petals (b) Zygote (c) Ovary (d) Ovule
(a) Shrivel and fall off.
(b) Divides many times to form an embryo.
(c) Ripens to form fruit
(d) Develops a tough coat and gets converted into seed.
Q.3) Name the parts A, B and C of the diagram given below. Write a function of the part B.
• A: Pollen grain
• B: Male germ cell
• C: Female germ cell
• Function of B: It fuses with the female germ cell to form zygote
Q.4) Differentiate between the process of binary fission and multiple fission giving an example of each.
In binary fission, the parent organism divides/splits into two cells/two equal halves during divisions.
e.g., Amoeba/Leishmania/Paramecium (any one example)
In multiple fission, the parent organism divides into many daughter cells simultaneously.
e.g., Plasmodium (any one example)
Q.5) What is Regeneration ? Explain the process of regeneration in Planaria.
• The process in which an individual is cut or broken up into many pieces and many of these pieces grow into separate individual.
• In Planaria regeneration is carried out by specialised cells, these cells proliferate, develop and differentiate into various cell types and tissues.
(the process can be explained with the help of diagram also.)
Q.6) (a) Differentiate between binary fission in Amoeba and binary fission in Leishmania. (b) How does reproduction take place in malarial parasite ?
(a) • In Amoeba, the splitting of the two cells during division can take place in any plane.
• In Leishmania, binary fission occurs in definite orientation in relation to its whip like structure.
(b) Malarial parasite/Plasmodium divides into many daughter cells simultaneously by multiple fission.
Q.7) Mention the functions of (a) Placenta (b) Fallopian tubes (c) Uterus and (d) Ovary in the human female reproductive system.
(a) Placenta—Helps in the transportation of glucose and oxygen from the mother to the embryo/ removal of waste
(b) Egg is carried from the ovary to uterus/ site of fertilisation
(c) Helps in the development of embryo/ implantation
(d) Production of female gamete or ovum/secretion of female sex hormone
Q.8) (a) State one drawback of each of the following :
(i) Oral contraceptive pills
(ii) Copper-T
(b) Under which category of contraceptive methods, is the use of condom kept ? In what way, its use is better as compared to other methods of contraception ?
(a) (i) change hormonal balance leading to side effects/cause hormonal imbalance
(ii) Irritation in the uterus
(b) ● mechanical barrier
● Prevents transmission of infections like STD’s
Q.9) In the following figure showing a germinating gram seed, name the parts labelled as A, Band C:
Why is part ‘B’ considered to be important during germination ?
• A - Plumule
B – Cotyledon
C - Radicle
• B provides stored food for the embryo
Q.10) Name the reproductive parts of an angiosperm. Where are these parts located ? Explain the structure of its male reproductive part.
• Stamen
• Pistil / Carpel
• Located in the flower
• The male reproductive part consists of anther and filament .
(labelled diagram of stamen can also be made)
Q.11) What is puberty ? Mention any two changes that are common to both boys and girls in early teenage years.
• The stage at which rate of general body growth begins to slow down and the reproductive tissues begin to mature.
Two common changes
(i) Thick hair growing in armpits and genital area.
(ii) Skin becomes oily.
(iii)Thin hair on legs and arms.
(or any other) (any two)
Q.12) (a) Name the reproductive and non-reproductive parts of bread mould (Rhizopus). (b) List any two advantages of vegetative propagation.
(a) Reproductive part of bread mould—Sporangia / Spores
Non-reproductive part of bread mould—Hyphae
(b) (i) Plants raised by vegetative propagation can bear flowers and fruits much earlier than those produced from seeds.
(ii) It is important for plants that have lost the capacity to produce seeds.
(iii) All plants formed by this method are genetically similar to the parent plant and have all its characteristics.
(Any two points)
Q.13) Give reasons :
(i) Placenta is extremely essential for foetal development.
(ii) Uterine lining becomes thick and spongy after fertilisation.
(i) Placenta is extremely essential because it
• provides nutrients /glucose / oxygen to the growing embryo.
• removes waste generated by embryo by transferring them into mother’s blood through it.
(ii) Uterine lining becomes thick and spongy which is required to provide nourishment to the fertilised egg (embryo).
Q.14) (a) In the given diagram, name the parts where (i) pollen grains are produced, and (ii) pollen grains are transferred.
(b) What happens to ovule and ovary after fertilisation ?
(a) i) Part—D Anther /Stamen
ii) Part—A Stigma
(b) Ovule converts into Seed; Ovary converts into Fruit
Q.15) Name the part/organ of the human female reproductive system
(a) where contraceptive devices such as loop or copper-T are placed to prevent pregnancy.
(b) which is blocked to prevent the transfer of eggs.
(c) where formation of green cells as ova takes place.
(d) from where the embryo gets nutrition from mother’s blood.
(a) Uterus
(b) Fallopian tube or oviduct
(c) Ovary / As question has printing error, half mark is awarded to all students irrespective of attempted/non attempted
(d) Placenta
Q.16) Suggest any two contraceptive methods to control the size of human population and explain them.
• Barrier method : Prevents the meeting of sperms with ova
• Oral pills/Chemical method : Changes the hormonal balance in females so eggs are not released.
• Copper T or loop : to prevent pregnancy/to prevent fusion of male & female gametes
• Surgical method : To block vas deferens in males or fallopian tube in females to prevent fertilization
(Any two)
Q.17) (a) Which of the following flowers will have higher possibility of self-pollination ?
Mustard, Papaya, Watermelon, Hibiscus
(b) List the two reproductive parts of a bisexual flower.
a) Mustard and Hibiscus
b) Stamens and Pistil / Carpel
Q.18) (a) Name the process shown below and define it :
(b) Name the types of cells present in the organisms which exhibit this process.
(a) • Regeneration
• It is a process in which each cut or broken up pieces of an individual grows into a new individual through specialised cells.
(b) • Specialized cells
Q.19) Which one of the two multicellular organisms Spirogyra and Planaria reproduces by regeneration and why ? Give an example of any other organism which can also reproduce by the same process.
• Planaria
• Regeneration is carried out by specialised cells which are not present in spirogyra.
• Hydra
Q.20) (a) What happens when in a human female the egg released by the ovary is not fertilised ?
(b) Name one bacterial and one viral infection caused due to unsafe sex.
(a) If the egg is not fertilized, it lives for about one day and the uterine lining formed to receive the fertilized egg slowly breaks and comes out through the vagina as blood and mucous along with unfertilized egg.
(b) Bacterial infection: Gonorrhoea/Syphilis.
Viral infection: Warts / AIDS.
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