Frank ICSE Class 10 Solutions

Frank ICSE Class 10 Biology Solutions – Nervous System

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Frank ICSE Class 10 Biology Solutions – Nervous System

PAGE NO 115
Solution 1:

  1. Central Nervous System
  2. Autonomic Nervous System
  3. Conus medullaris / Medullary cone
  4. Mixed neurons
  5. Neuroscience
  6. Sensory neurons
  7. Motor neurons
  8. White matter
  9. White matter
  10. Dura mater
  11. Neuron
  12. Meninges
  13. Cranium
  14. Neocortex / Neopallium
  15. Limbic system
  16. Corpora quadrigemina
  17. Olfactory Lobes
  18. Median fissure
  19. Agraphia
  20. Brain
  21. Aphasia
  22. Trigeminal nerve
  23. Sympathetic nervous system
  24. Dendrites
  25. Bipolar neuron
  26. Sclera
  27. Myopia
  28. Semicircular canal
  29. Rhodopsin

PAGE NO : 116
Solution 2:

  1. Ear pinna – The pinna or the external ear collects the sound waves from different directions and send them to the middle ear.
  2. External auditory meatus It forms a passage from the pinna to the eardrum.
  3. Cochlea – It converts vibrations into nerve impulses and thus helps in hearing.
  4. Semicircular canals – It responds to change in position and maintains balance.
  5. Lachrymal gland – It secretes a watery fluid which washes the surface of eyes.
  6. Eyelids – It blinks to clean the dust and grit from the cornea.
  7. Retina – It is a photosensitive layer to receive the image.
  8. Eye lens – It focuses the image on the retina.
  9. Pupil – It regulates the amount of light that enters the eye.
  10. Olfactory lobe – These are concerned with the sense of smell.
  11. Optic lobe – These are concerned with vision.
  12. Medulla oblongata – It controls involuntary functions of the body like – coughing, swallowing, breathing, heartbeat, etc.

Solution 3:

  1. Nephron
  2. Blind spot
  3. Myelin
  4. Olfactory lobe
  5. Cranial nerve

Solution 4:
Frank ICSE Class 10 Biology Solutions - Nervous System 1

Solution 5:

  1. Nerve impulse – It is an electrochemical change occurring in the membrane of a nerve fibre produced by a stimulus.
  2. Axon – It is a fibre like process of the neuron which carries impulses away from the cell body.
  3. Cyton – It is an oval, angular, polygonal or stellate body which contains a large central nucleus.
  4. Action potential – A momentary change in electrical potential on the surface of a cell, or a nerve or muscle cell, that occurs when it is stimulated, resulting in the transmission of an electrical impulse.
  5. Reflex action – It is an immediate and involuntary response to a stimulus.
  6. Yellow spot – It is the region of best vision where more cone cells are present.
  7. Blind spot – It is the region of no image formation because of lack of cone cells.
  8. Power of accommodation – It is the ability of the lens to focus on far and distant objects.

Solution 6:
Frank ICSE Class 10 Biology Solutions - Nervous System 2
Frank ICSE Class 10 Biology Solutions - Nervous System 3

Solution 7:
Frank ICSE Class 10 Biology Solutions - Nervous System 4

PAGE NO : 117
Solution 8:
Frank ICSE Class 10 Biology Solutions - Nervous System 5

Solution 9:
Frank ICSE Class 10 Biology Solutions - Nervous System 6

Solution 10:

  1. A – Cerebrum; B – Cerebellum; C – Medulla oblongata
  2. (A) Cerebrum – It is concerned with intelligence, memory and voluntary activities.
  3. Cerebellum – It is concerned with body equilibrium.
  4. Medulla oblongata It controls all involuntary activities like heart beat, respiration, etc.
    The three protective membranes covering the brain are :

    •  Dura mater
    • Arachnoid mater
    • Pia mater.
  5. Neuron is the basic unit of the brain.

PAGE NO : 118

Solution 11:

  1. Meninges – It is located around the brain and spinal cord.
  2. Ganglia – It is located outside the brain and spinal cord.
  3. Cerebellum – It is located behind cerebrum and above medulla oblongata in the brain.
  4. Nodes of Ranvier – It is located on the unmyelinated areas on the axon.
  5. Effector organs – It is located in muscle , gland or any organ of the body.

Solution 12:
Frank ICSE Class 10 Biology Solutions - Nervous System 7

Solution 13:
Frank ICSE Class 10 Biology Solutions - Nervous System 8

Solution 14:

  1. Iris: It is located in the eye. Its function is to protect the eyeball and controls the size of the pupil.
  2. Semicircular canals: It is located in the inner ear. These are concerned with the body equilibrium.

Solution 15:
Following are the two examples of reflex actions in our daily life :

  1. Removing hand suddenly when pricked by a thorn.
  2. Blinking of eyelids on exposure to light.

Solution 16:

  1. Reflex action – It is an immediate and involuntary response to a stimulus.
  2. Example of a conditioned reflex: Tying one’s shoe lace.

Solution 17:

  1. (a) Bone of skull
  2. (b) Inner ear
  3. (c) Eardrum
  4. (d) Bone of skull
  5. (e) Bone of middle ear
  6. (f) Middle ear
  7. (g) Air filled
  8. (ii) (b) Inner ear – It transmits the impulse to brain.
  9. (d) Bone of skull – It helps in fixing the position of the ears to help the brain use auditory cues to judge direction and distance of sounds.
  10. (g) Air filled – It keeps the pressure in the middle ear equalized with pressure in the outside.
  11. (iii) The main division of the ear are: outer ear, middle ear and inner ear.
  12. (iv) Stirrup
  13. (v) The labyrinth is the inner ear which consists of utriculus, sacculus, cochlea and three semicircular canals.

Solution 18:

  1. A – Semi-circular canal
    B – Utriculus
    C – Sacculus
    D – Cochlea
    (ii) Auditory nerve.
    (iii) 1. Utriculus and sacculus
  2. Semi-circular canal
  3. Cochlea
  4. Sensory cells of organ of Corti
  5. Perilymph

Solution 19:

  1. Cochlea – It helps in hearing by transmitting impulses to the brain through auditory nerves.
  2. Fovea centralis – It is a point at retina where more cone cells are concentrated and thus produces sharpest vision.
  3. Three semicircular canals – It maintains the dynamic equilibrium.
  4. Retina – It prevents the reflection of light.
  5. Lachrymal glands – It produces tear to lubricate the eyeball.

Solution 20:
The arrangement of neurons in
Cerebrum: cytons are present outside and axons are inside
Spinal cord: cytons are present inside and axons are outside.

Solution 211:
Functions of medulla oblongata –

  1. It controls the involuntary activities like – respiration, circulation, digestion, etc.
  2. It controls the dilation and constriction of blood vessels.

Solution 22:
Reflex action – It is an immediate and involuntary response to a stimulus.
Example – 1. Blinking of eyelids on exposure to light .
2. Knee jerk.

PAGE NO : 119

Solution 23:
Frank ICSE Class 10 Biology Solutions - Nervous System 9

Solution 24:
Cone cells.

Solution 25:
Frank ICSE Class 10 Biology Solutions - Nervous System 10

Solution 26:
Frank ICSE Class 10 Biology Solutions - Nervous System 11

Solution 27:

  1. Cochlea: It helps in hearing by transmitting impulses to the brain through auditory nerves.
  2. Meninges: It provides protection to brain and spinal cord.

Solution 28:
One feels blinded for a short while on coming out of a dark room.This is called light adaptation of the eye.It is due to the constriction of the pupil to prevent the entry of light into the eye and pigment rhodopsin is bleached to reduce the sensitivity of the rods.

Solution 29:

  1. Iris
  2. Cerebrospinal fluid

Solution 30:

  1. True
  2. True
  3. True
  4. True
  5. False
  6. True
  7.  False
  8. False

PAGE NO : 120
Solution 31:

  1. (d) nerve cell
  2. (b) cerebrum
  3. (a) 31
  4. (b) 12
  5. (a) dura mater
  6. (a) ear
  7. (c) rhodopsin
  8. (a) twilight vision
  9. (d) macula
  10. (d) two nerves
  11. (c) hearing
  12. (b) 31
  13. (a) eustachian
  14. (c) iris
  15. (b) cones
  16. (b) Ear
  17. (d) corpus callosum
  18. (d) eye
  19. (d) filter light
  20. (b) the two cerebral hemispheres

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Frank ICSE Class 10 Biology Solutions – Excretory System

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Frank ICSE Class 10 Biology Solutions – Excretory System

PAGE NO : 97
Solution 1:
Separation and elimination of the metabolic nitrogenous wastes from the body is called excretion.
Kidneys, skin and lungs are important excretory organs.

Solution 2:
Carbon dioxide (CO2) and urine

Solution 3:
Ammonia is toxic in even small amounts and therefore it must be removed from the body. The urea cycle or the orinithin cycle, in the liver, involves the conversion of ammonia into urea. Then the urea is then transported to the kidneys where it is excreted.

Solution 4:
Nephron is the basic structural and functional unit of the kidney.
Its chief function is to regulate the concentration of water and soluble substances like sodium salts by filtering the blood, reabsorbing what is needed and excreting the rest as urine.

Solution 5:
Frank ICSE Class 10 Biology Solutions - Excretory System 1

PAGE NO : 98
Solution 6:
Dialysis is a process of separation of toxic substances from the blood stream through a membrane by kidney machine or artificial kidney.

Solution 7:

  1. Ammonotelic.
  2. Ureotelic.
  3. Uricotelic.
  4. Liver.
  5. Nephron.
  6. Urinary Bladder.
  7. Glomerulus.

Solution 8:

  1. Vein
  2. Heart
  3. Haemoglobin
  4. Glomerulus
  5. Nerve
  6. Brain

Solution 9:

  1. Separation and elimination of the metabolic nitrogenous wastes from the body is called excretion.
  2. Nephron.
  3. The cortex of kidney shows dotted appearance because it contains numerous complex structures called nephrons.
  4. Formation of urine and osmoregulation are important functions of kidney.

Solution 10:

  1. (a) kidney
  2. (a) pigeon
  3. (c) haematuria
  4. (d) anuria
  5. (d) Nothing will happen
  6. (a) liver
  7. (b) urease
  8. (b) vitamin C
  9. (b) liver
  10. (c) nephron
  11. (b) renal papilla

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Frank ICSE Class 10 Biology Solutions – Circulatory System

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Frank ICSE Class 10 Biology Solutions – Circulatory System

PAGE NO : 90
Solution 1: Circulatory system: It is a system of organs that takes part in the flow of materials in the body of an organism inside an extracellular fluid.
Circulatory system in humans:

  1. The right atrium receives deoxygenated blood from all the parts of the body through large veins called vena cava.
  2. When the right atrium is full of blood, it contracts and the blood is forced into right ventricle.
  3. When the right ventricle is full of blood, it contracts and the blood is pumped into the pulmonary trunk.
  4. From right ventricle, the pulmonary artery carries the blood to the lungs for oxygenation.
  5. The oxygenated blood returns to the heart via pulmonary veins that empty into the left auricle.
  6. When the left auricle contracts, the blood passes into the left ventricle by the opening of bicuspid valve.
  7. On contraction of the left ventricle, the blood is pumped into the artery called aorta.
  8. The aorta branches into vessels which transports blood to the heart and all the body parts.

Solution 2:

  1. The SA is also called the pacemaker because it establishes the basic frequency at which the heart beats. It starts each heart beat and sets the pace for the whole heart.
  2. There is no mixing of deoxygenated and oxygenated blood in the human heart because of double circulation of blood where the blood passes twice through the heart and the right half of the heart is concerned with pumping deoxygenated blood while the left is concerned with pumping of oxygenated blood.
  3. The closed circulatory system is more efficient than the open system because in closed system the blood flows inside arteries or veins all the time which stops the mixing of blood with other bodily fluids and helps the transport of the blood around the body.
  4. The left ventricle possess a thicker wall than the right ventricle because it pumps the blood at a higher pressure since blood from the left ventricle goes to all areas of the body while the right ventricle only has to pump blood to the lungs which is a much shorter distance, therefore less pressure is required.

Solution 3:
Frank ICSE Class 10 Biology Solutions - Circulatory System 1

Solution 4:
The functions of blood plasma : It transports gases and other materials, maintains blood pH, body immunity, body heat regulation and also regulates the osmotic pressure of the blood.

Solution 5:
Double circulation means during one circulation blood passes twice through the heart. It includes both pulmonary and systemic circulation. It is necessary as it keeps oxygenated and deoxygenated blood separate.

Solution 6:
The materials which are carried by the blood are: oxygen, carbon dioxide, water, digested food, organic wastes, hormones and antibodies.

Solution 7:
The main function of erythrocytes is to transport the respiratory gases – CO2 and O2.

Solution 8:

  1. Fibrinogen
  2. Phagocytosis
  3. Haemoglobin
  4. Auricular systole
  5. Angiology
  6. Pericarditis
  7. Tricuspid valve
  8. Foramen ovale
  9. Polycythemia
  10. Lubb

PAGE NO : 91
Solution 9:

  1. Histone
  2. Foramen ovales
  3. Nerve
  4. RBC
  5. Albumin

Solution 10:

  1. Inferior vena cava, superior vena cava and coronary sinus
  2. Ventricles
  3. Function of bicuspid valve: It prevents the reverse flow of blood from the left ventricle into the left auricle.
  4. Function of tricuspid valve: It prevents the reverse flow of blood from the right ventricle into the right auricle.

Solution 11:
Frank ICSE Class 10 Biology Solutions - Circulatory System 2

Solution 12:

  1. (c) Pulmonary vein
  2. (b) Thebasius valve
  3. (d) Aorta
  4. (e) Pulmonary arch
  5. (a) Clotting

Solution 13:

  1. (d) 5 l
  2. (c ) Left ventricle
  3. (b) Capillaries
  4. (a) bone marrow
  5. (c ) 120 days
  6. (a) myogenic
  7. (a) Eustachian valve
  8. (c ) ventricle
  9. (b) 70-80
  10. (c ) Monocytes
  11. (d) 90%
  12. (c) William Harvey
  13. (b) Spleen
  14. (d) all the above
  15. (d) O

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Frank ICSE Class 10 Biology Solutions – Photosynthesis

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Frank ICSE Class 10 Biology Solutions – Photosynthesis

PAGE NO : 74
Solution 1:
Frank ICSE Class 10 Biology Solutions - Photosynthesis 1

Solution 2:

  1. Plant pigments – Plant pigments are a variety of different kinds of molecules present in plants that absorb certain wavelengths of light while reflecting others.
  2. Quantum – Quantum are the discrete packets which stores energy and these particles can be changed from one form to another.
  3. Organic food – The food that is produced by using methods that do not involve synthetic inputs such as synthetic pesticides and chemical fertilizers is called organic food.
  4. Light reaction – The reaction of photosynthesis which takes place in the presence of light is called light reaction.
  5. Photolysis in photosynthesis – The process of splitting of water by sunlight during light reaction of photosynthesis is called photolysis in photosynthesis.

Solution 3:
Frank ICSE Class 10 Biology Solutions - Photosynthesis 2

Solution 4:
Frank ICSE Class 10 Biology Solutions - Photosynthesis 3

Solution 5:

  1. The aim of the experiment is to prove that CO2 is necessary for photosynthesis.
  2. Potassium hydroxide absorbs CO2 from the surrounding. It is placed to remove CO2 within the conical flask.
  3. The leaf inside the conical flask would be tested for the presence of starch by the application of iodine.
  4. The expected result of the above test is – No change in the colour will be observed.
  5. Yes, it is necessary to similarly test on the outer leaf also to show that leaves present in CO2 show photosynthesis.

Solution 6:

  1. 1 – Upper Epidermis; 2 – Palisade layer / chloroplast; 3 – Xylem; 4 – Phloem; 5 – Guard cell
  2. The two arrows show the release of oxygen and water vapours during the daytime and carbon dioxide and very less amount of oxygen is released during the night.
  3. Yes, one more arrow can be added to show the absorption of carbon dioxide by the leaf.
  4. One vein has been shown in this section.

Solution 7:
Frank ICSE Class 10 Biology Solutions - Photosynthesis 4

Solution 8:
Frank ICSE Class 10 Biology Solutions - Photosynthesis 5

Solution 9:
Frank ICSE Class 10 Biology Solutions - Photosynthesis 6

PAGE NO : 75
Solution 10:

  1. The objective of this experiment is to prove that oxygen is released during photosynthesis.
  2. Hydrilla
  3. Oxygen
  4. The rate of photosynthesis will increase and the rate of bubbling also increases when sodium bicarbonate is added.
  5. Photosynthesis will not take place.

Solution 11:

  1. The leaf is then treated with iodine solution.
  2. The leaf from first plant will not show starch test while the leaf from second plant will become blue-black showing the presence of starch.
  3. It is necessary to grease the glass sheet to prevent the entry of air containing CO2.
  4. The hypothesis that CO2 is necessary for photosynthesis is being tested in this experiment.

Solution 12:
Light intensity is directly proportional to sunlight. Increase in intensity of light increases the rate of photosynthesis. Photosynthesis is maximum in red light followed by blue light and is least in green light.

Solution 13:

  1. Advantages of photosynthesis:
    • To produce food for all the organisms on earth.
    • Release oxygen which is a life supporting gas.
  2. Respiration is a catabolic process while photosynthesis is an anabolic process. During respiration oxygen is taken and carbon dioxide is given out while during photosynthesis carbon dioxide is taken and oxygen is given out.
  3. Chlorophyll is a green coloured pigment found in green plants. it absorbs light energy which is utilized for the formation of ATP and reduction of NADP during photosynthesis.

Solution 14:
Frank ICSE Class 10 Biology Solutions - Photosynthesis 7

Solution 15:
Frank ICSE Class 10 Biology Solutions - Photosynthesis 8

Solution 16:
Coelus and mushroom.

Solution 17:
It is because the upper surfaces of broad leaves are directly exposed to sunlight which leads to maximize the rate of photosynthesis.

Solution 18:
Frank ICSE Class 10 Biology Solutions - Photosynthesis 9

Solution 19:
Chlorophyll.

Solution 20:
True

Solution 21:
False

Solution 22:
During the day transpiration and photosynthesis are interlinked as the stomata opens to facilitate the inward diffusion of carbon dioxide for photosynthesis which also leads to loss of water vapours to the outside during transpiration.

PAGE NO : 76
Solution 23:

  1. Destarched plant is the plant which lacks starch. Destarching is done by keeping the plant in dark for 2-3 days or covering a part of a leaf with a black paper by clip.
  2. (a) The leaf is plucked and is boiled in water and decolourized with alcohol.
    (b) The portion of leaf which received light turns blue with iodine because photosynthesis took place in that part of leaf.
    (c) The part of leaf which was covered with black paper remains colourless because photosynthesis could not take place in the absence of sunlight.

This shows that starch is not manufactured in the absence of light.

Solution 24:

  1. Chloroplast.
  2. Glucose and oxygen.
  3. Fungi, insects and animals.
  4. Photolysis.
  5. Magnesium.
  6. Chloroplast.

Solution 25:

  1. True
  2. True
  3. False
  4. True
  5. True
  6. True
  7. False
  8. False
  9. True

Solution 26:

  1. Photosynthesis
  2. Atmosphere
  3. Glucose
  4. Yellow
  5. Chloroplast
  6. Glucose and oxygen
  7. Stomata

Solution 27:

  1. (d) During night
  2. (e) Green plants
  3. (f) Oxygen
  4. (b) Light reaction
  5. (a) Decomposers

Solution 28:
Chloroplasts are the cell organelles in green plants which have chlorophyll and thus serve as the main site of photosynthesis.

Solution 29:

  1. Large surface area of leaves.
  2. Presence of more stomata.
  3. The thinness of leaves.

Solution 30:
Carbon cycle is a series of chemical reactions in which atmospheric carbon dioxide is used by the organisms and returned to the atmosphere. Photosynthetic plants use carbon as carbon dioxide from the air synthesizing organic compounds. By respiration, burning, decay, etc. the carbon is returned to the atmosphere.

Solution 31:
Carbon in the form of carbon dioxide enters living organisms and then goes back to the atmosphere through several pathways forming the true carbon cycle. Thus, it helps in maintaining the balance of nature.

Solution 32:
The amount of carbon dioxide in the atmosphere is increasing due to increased human activities like burning of fossil fuels, deforestation, etc. which cause the rise in global temperatures. This global warming result in melting of polar ice caps, floods in coastal areas, disturbance in hydrogenic cycle etc. Thus “Human activities are harmful to the balance of nature”.

Solution 33:
Carbon dioxide is removed from the atmosphere by:

  1. Producers – Producers or green plants use carbon dioxide through photosynthesis. A small amount of carbon dioxide is used by chemosynthetic bacteria also.
  2. Marine Organisms – Some amount of carbon dioxide is directly fixed by a few marine organisms and sea water absorbs carbon dioxide in the form of dissolved carbon dioxide, carbonic acid, carbonate and bicarbonates.

PAGE NO : 77
Solution 34:

  1. Carbon dioxide is returned back to the atmosphere mainly through the following ways:
    • Respiration – Animals and plants respire and release carbon dioxide in the atmosphere.
    • Decay – Plants and animals decay organic matter with the help of bacteria and fungi and release carbon dioxide.
    • Combustion – Plants and animals which got buried under the soil changed into coal and oil and releases carbon dioxide when these are burnt.
    • Ocean water – Carbon dioxide occurs in the form of lime stone in molluscan shells and as by product of photosynthesis in marine water.
  2. (i) To show that sunlight is needed for photosynthesis.
    (ii) Yes, the uncovered portion of the experimental leaf is the control.
    (iii) To destarch the leaf.
    (iv) 1. Boil the leaf in alcohol.

2. Wash the leaf in water to make it soft.
3. Add iodine solution on the leaf. The portion uncovered shows blue-black colour and the portion covered shows brown colour. This indicates that sunlight is needed for photosynthesis.

Solution 35:

  1. (e) 5
  2. (a) 1
  3. (b) 2
  4. (e) 5

Solution 36:

  1. leaves
  2. water
  3. hydrogen ion
  4. photolysis
  5. hydrogen
  6. NADPH2
  7. ATP
  8. photophosphorylation
  9. glucose
  10. polymerization

Solution 37:

  1. (d) 3.5
  2. (b) Oxygen
  3. (c) Water
  4. (c) Decrease because the temperature drops.
  5. (b) Increases because more photosynthesis occurs.

PAGE NO : 78
Solution 38:

Frank ICSE Class 10 Biology Solutions - Photosynthesis 10

Solution 39:

  1. (d) To stop synthesis process in the leaves.
  2. (c) Chloroplasts
  3. (d) split water
  4. (c) Palisade mesophyll
  5. (b) ADP
  6. (b) liberate O2
  7. (a) Grana
  8. (b) Red light
  9. (d) Carbon dioxide
  10. (d) water, carbon dioxide, chlorophyll and sunlight

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Frank ICSE Class 10 Biology Solutions – Transpiration

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Frank ICSE Class 10 Biology Solutions – Transpiration

PAGE NO:60
Solution 1:

  1. Transpiration: It is the loss of water in the form of water vapour from aerial parts of the plant.
  2. During transpiration, water comes out in the form of water vapour.
  3. Transpiration takes place in leaves through stomata. Stomata consist of guard cells, epidermal cells, chloroplast and nucleus.
  4. The important difference between transpiration and evaporation is that transpiration is the loss of water from the aerial parts of the plant while evaporation is loss of water from any surface.
  5. Stomatal transpiration occurs mainly during the day time when the guard cells of stoma are fully turgid and the stomata are fully open.
  6. Cuticular transpiration occurs through the cuticle which is present on the epidermis of leaves & herbaceous stem.
  7. Rate of transpiration slows down at night because photosynthesis does not take place and the stomata remains closed.
  8. There is a direct effect of temperature on transpiration as the increase in temperature results in increase in the rate of transpiration.
  9. When the atmospheric pressure is higher, less water vapour is lost and the rate of transpiration lowers.
  10. The relationship between transpiration water and water absorbed from the soil is that if the soil is deficient in water then the rate of water absorption decreases which hence decreases the rate of transpiration and if the soil has excessive water then the rate of water absorption increases which in turn increases the rate of transpiration.

Solution 2:
Frank ICSE Class 10 Biology Solutions - Transpiration 1

Solution 3:
There are three types of transpiration found in plants:

  1. Cuticular transpiration
  2. Lenticular transpiration
  3. Stomatal transpiration

Solution 4:
The transpiration occurs highest during the day time as with the increase in light intensity the rate of transpiration increases.

Solution 5:
Frank ICSE Class 10 Biology Solutions - Transpiration 2

Solution 6:
Frank ICSE Class 10 Biology Solutions - Transpiration 3

Solution 7:
The three means of water loss in plants are:

  1. Respiration
  2. Guttation
  3. Bleeding

PAGE NO :61
Solution 8:
The opening and closing of stomata depends upon the changes in the turgidity of their guard cells. Due to absorption of water the guard cells become turgid.Their inner walls are pulled apart by their outer wall.The gap between the guard cells become wider and stomata open.When guard cells are flaccid due to loss of water, the outer walls are not stretched , their inner walls are not pulled apart decreasing the gap between the guard cells and stomata close.
Frank ICSE Class 10 Biology Solutions - Transpiration 4
Solution 9:
Mechanism of stomata: Stomata are small pores present on the leaves which contains two kidney-shaped guard cells. The opening and closing of stomata depends upon the changes in the turgidity of their guard cells. Due to absorption of water the guard cells become turgid.Their inner walls are pulled apart by their outer wall.The gap between the guard cells become wider and stomata open.When guard cells are flaccid due to loss of water, the outer walls are not stretched, their inner walls are not pulled apart decreasing the gap between the guard cells and stomata close.
Frank ICSE Class 10 Biology Solutions - Transpiration 5

Solution 10:
Transpiration is important for plants because it evaporates excess water which produces a cooling effect to plants. This process also helps in ascent of sap and transportation of water and minerals to the various parts of the plants.

Solution 11:
Transpiration: It is the loss of water in the form of water vapour usually during day time.
Following are its importance in plants:

  1. It causes transpirational pull which helps in the absorption of water.
  2. It produces a cooling effect.
  3. It helps in the ascent of sap.

Solution 12:
The typical structure of stomata:
Stomata are minute pores of elliptical shape surrounded by two specialized epidermal cells called guard cells.These guard cells are kidney shaped which control the opening and closing of stomata.It also consists of nucleus, stoma, epidermis and chloroplast.
Frank ICSE Class 10 Biology Solutions - Transpiration 6

Solution 13:
Following are the importance of transpiration :

  1. It causes transpirational pull which helps in the absorption of water.
  2. It produces a cooling effect.
  3. It helps in the ascent of sap.

Solution 14:
Frank ICSE Class 10 Biology Solutions - Transpiration 7

Solution 15:

  1. A windy day: On a windy day the water vapour released from the leaves by transpiration is removed faster and the leaf does not get saturated with water. So, transpiration is more during a windy day.
  2. A foggy day: On a foggy day the area outside the leaf is saturated with water. So, water vapour from the leaves is removed very slowly thereby reducing transpiration.

Solution 16:
Transpiration increases the rate of water absorption because it causes the concentration of sap to rise. In this condition cells absorb water from their neighbours, leaf, stem and root which creates transpirational pull which finally helps in the absorption of water.

Solution 17:

  1. Potometer
  2. Potometer is used to measure the rate of transpiration.
  3. The rate of movement of the air bubble will indicate the rate of transpiration.
  4. The reservoir is used to provide water to the potometer.

Solution 18:

  1. Movement of the air bubble will be decreased or slow.
    Reason: During dark, stomata remains closed due to which the rate of transpiration decreases which hence decreases the movement of air bubble.
  2. Movement of the air bubble will be faster.
    Reason: During sunlight, stomata remains opened due to which the rate of transpiration increases which hence increases the movement of air bubble.
  3. Movement of the air bubble will be faster.
    Reason: Moving air produces dry air which increases the rate of transpiration which hence increases the movement of air bubble.

Solution 19:

  1. The level of mercury in the glass tube will rise.
  2. Transpiration
  3. Transpiration is the loss of water in the form of water vapour usually during day time.
  4. The three advantages of transpiration to the plant are:
    • It causes transpirational pull which helps in the absorption of water.
    • It produces a cooling effect.
    • It helps in the ascent of sap.
  5.  xylem

Solution 20:
A well-watered potted plant shows wilting of leaves on a hot sunny day. As during hot sunny day rate of transpiration is more than the rate of absorption of water.

Solution 21:
Xylem tissue

Solution 22:
Frank ICSE Class 10 Biology Solutions - Transpiration 8

Solution 23:
Stomata. Their main functions include exchange of gases and transpiration.

Solution 24:
Transpiration

Solution 25:
Potometer: It is an apparatus where the rate of the air bubble will indicate the rate of transpiration.It is used to measure the rate of transpiration.

Solution 26:
The three factors that enhance the rate of transpiration are:
1. High intensity of light 2. High temperature 3. Low humidity

PAGE NO :62
Solution 27:
Plants absorb more water than what is required. Out of 100%, only 5% of the water is used in metabolic reactions while the remaining 95% is released into the atmosphere as transpiration.
The three uses of this phenomenon are:

  1. It helps in transportation of water and minerals to the various parts of the plant.
  2. It produces a cooling effect to the plants.
  3. It evaporates excess water.

Solution 28:

  1. False
  2. Cobalt chloride (CoCl2) paper

Solution 29:
Frank ICSE Class 10 Biology Solutions - Transpiration 9

Solution 30:
Potometer is the instrument used for measuring the rate of transpiration.

Solution 31:
Cobalt chloride paper.

Solution 32:
False

Solution 33:
Loss of water as droplets through leaves of an intact plant is termed guttation.

Solution 34:
The three adaptations found in plants to reduce transpiration are:

  1. Sunken stomata
  2. Modification of leaves into spines
  3. Presence of thick cuticle

Solution 35:

  1. The aim of the experiment is to demonstrate transpiration.
  2. To prevent the evaporation of water from the surface.
  3. The level of water in test tube (a) will decrease.
  4. The fall in the water level in the test tube (a) is because of transpiration through aerial parts of the plant.
  5. Test tube (b) has been taken as a control experiment. Since no transpiration takes place without the plant.

Solution 36:

  1. (d) stop growing and gradually die of starvation.
  2. (a) open stomata, dry atmosphere and moist soil.

Solution 37:
Cuticle, lenticels and stomata are the three openings through which transpiration occurs.

Solution 38:
Hydathodes: Guttation

Solution 39:

  1. The plant was kept in the dark to destarch the leaves.
  2. Sodium hydroxide absorbs CO2 thereby making the flask CO2 free.
  3. (1) C, (2) E
  4. Sunlight

PAGE NO :63
Solution 40:

  1. To absorb the moisture formed by transpiration.
  2. Yes, the weight of CaCl2 vials kept on the lower side will be more because transpiration will be more on the lower surface and the moisture absorbed.
  3. To check the outside and inside pressure.
  4. Transpiration is the loss of water from the aerial parts of the plant in the form of water vapour.

Solution 41:

  1. A = Guard cell
    B = Stomatal aperture
  2. Stomata
  3. The function of the guard cells are that they help to regulate the rate of transpiration by opening and closing the stomata thus preventing excessive water loss.
  4. The two structural features of guard cells are :
    • The guard cells have thin outer wall and thick inner wall.
    • Guard cells contain chloroplast in their cytoplasm.
  5. These are present on the lower surface of the dorsiventral leaf.
  6. Transpiration is the loss of water in the form of water vapour from aerial parts of the plant.
  7.  Five

Solution 42:

  1. (b) Root pressure
  2. (d) environmental conditions may dry
  3. (a) do photosynthesis and synthesis osmotically active
  4. (d) Transpiration
  5. (d) hydathodes
  6. (b) guttation
  7. (b) From the lower surface of leaf
  8. (a) Potometer
  9. (c) 90
  10. (d) atmosphere is dry and temperature is high
  11. (c) layering the bottom with vaseline
  12. (a) approximately 10%
  13. (a) suction force
  14. (d) all of the above
  15. (a) xerophyte
  16. (a) Curtis

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Frank ICSE Class 10 Biology Solutions – Principles of Genetics

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Frank ICSE Class 10 Biology Solutions – Principles of Genetics

PAGE NO:35
Solution 1:
Gregor Johann Mendel.

Solution 2:
Genetics is the branch of biology that deals with the study of transmission of characters from parents to offspring.

Solution 3:
The term heredity may be defined as the transmission of genetically based characteristics from parents to offspring.

Solution 4:
Monohybrid cross.

Solution 5:
Dihybrid cross ratio is 9:3:3:1.

Solution 6:
Frank ICSE Class 10 Biology Solutions - Principles of Genetics 1

Solution 7:

  1. Genotype – The genetic expression of a character in terms of alleles written in symbols is called genotype.
  2. Phenotype – The physical or external and observable expression of a character is called phenotype.
  3. Homozygous – Diploid condition where both the alleles are identical is called homozygous.
  4. Heterozygous – Diploid condition where both the alleles are different is called heterozygous.
  5. Allele – Alternative forms of the same gene which determine contrasting characters is called an allele.
  6. Dominant – An allele which expresses itself externally when present in homozygous or heterozygous conditions.
  7. Recessive – An allele which expresses itself externally when present in homozygous condition but remains suppressed in heterozygous condition.

Solution 8:
Gregor Johann Mendel was a biologist who carried out experiments on garden pea and derived a few fundamental principles in genetics. He is called the ‘Father of Genetics’.

Solution 9:
Mendel’s laws are:

  1. Law of Dominance
  2. Law of Segregation
  3. Law of Independent Assortment

Solution 10:
Monohybrid cross is one where the parents used for hybridization differ in only one pair of contrasting characters or alleles.

Solution 11:
Frank ICSE Class 10 Biology Solutions - Principles of Genetics 2

Solution 12:
The law of segregation explains that the characteristics of an organism are determined by internal alleles that occur in pairs. These allele pairs separate during meiosis in gamete formation and the pair gets restored upon random fusion in zygote.

Solution 13:
Law of segregation is also called the law of purity of gametes because the two members of a pair of factors do not blend but segregate or separate into different gametes.

Solution 14:
According to the law of independent assortment when there are two pairs of contrasting characters, the distribution of the members of one pair into the gametes is independent of the distribution of the other pair.

Based on dihybrid ratio of 9:3:3:1 in F2 generation, Mendel observed that when a plant with two dominant alleles was crossed with another having the corresponding recessive alleles it was possible to obtain new combinations of characters where a plant had one dominant and the other recessive allele. These were new recombinations were not present in either parent or F1 generation.

PAGE NO :36
Solution 15:
Importance of Mendel’s Laws:

  1. Dominant and recessive characters can be found.
  2. A hybrid with desired characters can be produced easily.
  3. Crops can be improved.
  4. Pure recessive characters can be used where needed.
  5. Genotypes and phenotypes of next generation can be predicted even before cross is made.

Solution 16:
Exceptions to Mendel’s Laws:

  1. Incomplete Dominance – In few cases, F1 generation has an intermediate phenotype between dominant and recessive alleles.
  2. Linkage – Genes on the same chromosomes are said to be linked and are inherited together.
  3. Multiple Allelism – Each character may have more than two alleles which can’t be explained by Mendel’s laws.

Solution 17:
Mendel performed his experiments on the garden pea plant or Pisum sativum.

Solution 18:
Sex chromosomes determine the sex of a child in humans.

Solution 19:
Frank ICSE Class 10 Biology Solutions - Principles of Genetics 3

Solution 20:
Frank ICSE Class 10 Biology Solutions - Principles of Genetics 4

Solution 21:
Mendel’s work did not receive much notice till 1900. Then three scientists: Hugo de Vries, Carl Correns and Erich von Tschermak working independently rediscovered his work and brought Mendel’s experiment to limelight.

Solution 22:

  1. Autosomes – The chromosomes other than sex chromosomes present in the body are called autosomes.
  2. Sex chromosomes – The chromosomes which determine the sex of an individual are called sex chromosomes.
  3. Sex-linked characters – Such characters or traits that are controlled by genes occurring on sex chromosomes are called sex linked characters.

Solution 23:
The sex of the zygote is determined by the sperm which fertilizes the ovum. If an X bearing sperm fuses with an ovum in man, the offspring would be female and if a Y chromosome bearing sperm fuses with an ovum the offspring will be a boy.

Solution 24:
The inheritance of sex linked genes controlling sex linked characters is called sex linkage or sex linked inheritance.

Solution 25:
Haemophilia is X-linked inherited disease in which the diseased person is unable to synthesize a normal blood protein called Antihaemophilic globulin that helps in clotting. Haemophilia is also called Bleeder’s disease as the haemophilic person bleeds for a long time even from a minor cut.

Solution 26:
Colour blindness is a sex-linked inherited disease in which the diseased person is not able to distinguish between red and green colour.

Solution 27:
Cause of Haemophilia – Haemophilia is an X-linked inherited disease. Homozygosity for recessive haemophilia gene is must to be seen in a female while a single affected X chromosome makes the male a haemophilia victim.
Cause of Colour Blindness – Colour blindness is the effect of a recessive gene. In case of female, both the X chromosomes must have the recessive gene but as males have only one X chromosome, just a single affected chromosome causes colour blindness.

Solution 28:
More males are affected by sex linked diseases because they have a single X chromosome and the sex linked diseases occur due recessive gene on X chromosome.

Solution 29:
A man can never transfer a sex-linked gene directly to his son because the son inherits only the Y chromosome from his father and the sex linked diseases are present on the X chromosome.

Solution 30:
The progeny of the woman and the haemophilic man will have one son and one daughter as colorblind, one daughter as a carrier and one son will be normal.

Solution 31:
Haemophilia

Solution 32:
The inheritance of sex linked genes controlling sex linked characters is called sex linkage or sex linked inheritance.

Solution 33:
Frank ICSE Class 10 Biology Solutions - Principles of Genetics 5

Solution 34:
Frank ICSE Class 10 Biology Solutions - Principles of Genetics 6

PAGE NO :37

Solution 35:

  1. Father is color blind.
  2. 3 daughters and two sons.
  3. Child 1 is color blind.
  4. All daughters from 2-5 are carriers while all the sons are normal.
  5. X chromosome.
  6. Haemophilia.

Solution 36:

  1. (b) garden pea
  2. (d) 100%
  3. (c) 7
  4. (d) Mendel
  5. (a) dominant
  6. (c) Law of Independent Assortment
  7. (a) alleles
  8. (b) heterozygous
  9. (a) dihybrid cross
  10. (a) Czechoslovakia
  11. (c) X and Y
  12. (a) X chromosome
  13. (b) autosomes
  14. (b) one X chromosome
  15. (b) X chromosomes in male
  16. (c) 50%
  17. (c) sons are colour blind and daughters are carriers
  18. (b) daughter

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Frank ICSE Class 10 Biology Solutions – Structure of Chromosomes

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Frank ICSE Class 10 Biology Solutions – Structure of Chromosomes

PAGE NO-20:
Solution 1:
Chromatin is an extremely thin, long nuclear fibre occurring in the nucleus before cell division.

Solution 2:
In interphase, the chromatin appears as a network of long, extremely thin fibres.

Solution 3:
During prophase of mitosis, the chromatin fibres shorten and become thick to form chromosomes.
During metaphase, the chromosomes appear more distinct and clear and each consists of two parallel strands called chromatids joined by a centromere.

Solution 4:
Chromosomes are the thread like structures or chromatin material present inside the nucleus.
Chromosomes are so called because they take up certain basic dye and stain very rapidly. The word chromosome comes from two words “chromos” meaning colour and “soma” meaning body.

Solution 5:

  1. Strasburger – He observed thread like structures during cell division.
  2. Balbiani – Described rod like structures in nucleus before cell division.
  3. Waldeyer – Coined the term ‘chromosomes’.
  4. Sutton and Boveri – They described chromosomes as physical structures and transmitters of hereditary traits.

Solution 6:
Chromosomes are the thread like structures present in the nucleus of the cell. They are covered with a sheath made up of proteins and filled with granular matter called matrix. Inside the matrix, there are two threads called chromonemata.
The chromosome consists of two symmetrical strands called chromatids. Each chromosome consists of a distinct constriction called centromere which gets attached to the spindle network.
Frank ICSE Class 10 Biology Solutions - Structure of Chromosomes 1

Solution 7:

  1. Sheath – It is a proteinaeous covering present around the chromosomes.
  2. Matrix – It is a granular matter present inside the sheath.
  3. Chromonemata – They are the subunits of chromatids.
  4. Centromere – A constriction in the chromosome is called centromere.
  5. Secondary Constriction – A constriction other than primary constriction is called a secondary constriction.
  6. Telomere – The ends of the chromosomes is termed as telomere.

Solution 8:
Chromosomes are best observed at metaphase

Solution 9:
The chromosomes other than sex chromosomes present in the human body are called autosomes.
22 pairs of autosomes are present in man.

Solution 10:
The chromosomes which determine the sex of an individual are called sex chromosomes.

Solution 11:
Sex chromosomes are significant as they determine the sex of an individual.

Solution 12:
In man, there is a pair of sex chromosomes. In males, it is X and Y while in female, the sex chromosomes are X and X which are identical to each other.

Solution 13:
Chromosomes are the main source of chemical information which determines that the cell should become like its parent cell.

During the developmental stage they also determine that the cells of the organism will give the animal or the plant, the characteristic features of its species.

Solution 14:
DNA and RNA are the two nucleic acids.
Frederick Miescher discovered DNA

Solution 15:
Nucleic acids are made up of three types of molecules:

  1. a pentose sugar,
  2. nitrogenous bases
  3. a phosphate

Solution 16:
The chemical composition of chromosome consists of:

  1. Approximately 40% of DNA
  2. 50% of Histone proteins
  3. 8.5% Non histone proteins
  4. Metallic ions like magnesium and calcium in traces.

Solution 17:
Two nitrogenous bases present in DNA are:

  1. Purines – Adenine and Guanine.
  2. Pyrimidines – Cytosine and Thymine.

Solution 18:
Frank ICSE Class 10 Biology Solutions - Structure of Chromosomes 2

Solution 19:
Features of DNA:

  1. DNA consists of two strands which are spirally arranged around an axis. This is called a double helical arrangement.
  2. Each DNA strand is made up of nitrogenous bases, pentose sugar and phosphate.
  3. Sugars are pentose type; bases are adenine, guanine, cytosine and thymine.
  4. Both strands are connected with hydrogen bonds. There are two bonds between adenine and thymine and three bonds between guanine and cytosine.
  5. In the DNA, bases are inside and sugars are outside and two sugars are connected with phosphoric acid.
  6. Each DNA strand replicates and from each replicated DNA a new DNA is formed. This is called replication of DNA.

Solution 20:
Watson and Crick described the detailed structure of DNA.

Solution 21:
Importance of DNA:

  1. DNA is most important because it is the hereditary material.
  2. It acts as the director of protein synthesis.
  3. Some DNA of chromosomes forms nucleolus.
  4. DNA in presence of enzymes forms mRNA which acts as messenger.

Solution 22:
The rungs of “DNA ladder” are made up of two types of nitrogenous bases:

  1. Purines: Adenine and Guanine
  2. Pyrimidines: Cytosine and Thymine.

Solution 23:
Repeating components of each DNA strand length wise are pentose sugar and phosphate group

Solution 24:

  1. Interphase
  2. histone proteins
  3. RNA, DNA
  4. Protein
  5. Nitrogen

PAGE NO 21
Solution 25:

  1. False
  2. False
  3. True
  4. True

Solution 26:

  1. This diagram represents the structure of chromosome.
  2. ‘d’ is centromere which gets attached to the spindle fibres.
  3. ‘b’ is heterochromatin which is darkly stained region when stained with acetocarmine and ‘c’ is euchromatin which when stained with acetocarmine or felugen gets lightly stained.
  4. Waldeyer
  5. Matrix
  6. No, secondary constriction or ‘e’ is not present in all chromosomes.

Solution 27:

  1. (d) chromatin
  2. (c) Waldeyer
  3. (a) centromere
  4. (c) secondary constriction
  5. (a) interphase
  6. (d) prophase
  7. (a) DNA and histones
  8. (a) 46
  9. (a) I shaped
  10. (b) metacentric
  11. (c) XY
  12. (b) sex chromosomes
  13. (a) Watson and Crick
  14. (a) nitrogen base
  15. (c) Uracil
  16. (b) thymine
  17. (a) DNA

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Frank ICSE Class 10 Biology Solutions – Cell Division

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Frank ICSE Class 10 Biology Solutions – Cell Division

PAGE NO-11:
Solution 1:
Cell division is important for a variety of reasons. One reason is that cell division is important for the growth of an organism. It is also important for cells to divide so that they can remain efficient. As all the cells are produced by the division of pre-existing cells, so each organism needs new cells for growth, replacement, repair and reproduction.

Solution 2:
The cell cycle is a series of events that take place in a cell leading to its division and duplication

Solution 3:
Interphase is a long resting phase in the cell cycle during which the cell grows, multiplication of DNA, synthesis of RNA and proteins takes place. Thus interphase is important in the cell cycle as it allows the cell to grow and develop into a mature cell before it is able to reproduce.

Solution 4:
Meiosis results in the formation of ova.

Solution 5:
Frank ICSE Class 10 Biology Solutions - Cell Division 1

Solution 6:
In anaphase, the two chromatids separate at the centromere and begin to move in opposite direction towards either end of the spindle network called the poles. The chromosomes bend around the centromere showing a ‘V’ or ‘J’ or ‘L’ shaped structure based on the length of its arms.

Solution 7:
The different phases of mitosis are Prophase, Metaphase, Anaphase and Telophase.

Solution 8:
Mitosis takes place in the body cells or somatic cells of the organisms.

Solution 9:
Mitosis is important because:

  1. It helps in the growth of tissues, organs and thus the entire organism.
  2. It helps in the repair of damaged tissues and organs.
  3. It is the method by which lower organisms reproduce.
  4. It helps in the maintenance of the hereditary characters by the replication of chromosomes

Solution 10:
Some characteristic features of mitosis are:

  1. It takes place in somatic cells.
  2. Chromosome number is preserved.
  3. Daughter cells produced are identical to the parent cell.
  4. It results in increase in the number of cells.

Solution 11:
Few important characteristics of Meiosis are:

  1. Meiosis occurs in germ cells only.
  2. It results in the formation of gametes.
  3. Chromosome number of the parent cell is halved.
  4. Daughter cells differ from the parent cell.

Solution 12:
Frank ICSE Class 10 Biology Solutions - Cell Division 2

Solution 13:
In humans, meiosis occurs in testes producing sperms and in the ovaries resulting in ova.

Solution 14:
Significance of Meiosis:

  1. Due to meiosis, chromosome number is reduced to half in gametes and chromosome number of species is maintained.
  2. Genetic variations occur due to meiosis.
  3. The zygote on fertilization gets one maternal and one paternal chromosome in each homologous pair.

Solution 15:
Significance of Crossing over:

  1. As a result of crossing over, the paternal and maternal homologous chromosomes of an organism pair up and exchange certain portions of their chromatids which lead to genetic variations.
  2. It makes the genetic information in each haploid cell unique

Solution 16:
Frank ICSE Class 10 Biology Solutions - Cell Division 3

Solution 17:
No, cytokinesis is not necessary after karyokinesis in meiosis I. It generally takes place at the end of meiosis II when the four daughter cells are formed.

Solution 18:

  1. Karyokinesis – It is the nuclear division where nucleus divides into two.
  2. Cytokinesis – It is the division of cytoplasm in which the entire cell splits separating each nuclei.
  3. Chiasmata – is the point where two homologous non-sister chromatids exchange genetic material in chromosomal crossover during meiosis.

Solution 19:
In an animal cell, the cytoplasm between the two daughter nuclei constricts i.e. a furrow starts forming in the plasma membrane at the middle. This deepens towards the interior of the cell and the cytoplasm splits into two similar daughter cells.
In plant cells on the other hand, the constriction is not observed during cytokinesis. Instead a new cell wall is laid down along the equatorial region of the spindle network beginning at the centre. Thus, two distinct, daughter cells are cut off.

Solution 20:
Frank ICSE Class 10 Biology Solutions - Cell Division 4

Solution 21:
Meiosis is a reductional division as in meiosis the number of chromosomes of parent cell is reduced to half in the daughter cells. Now, this reductional division is significant because it restores the number of chromosomes in a species.

PAGE NO-12:
Solution 22:
Yes, meiosis is responsible for maintaining the chromosome number of a species as meiosis being a reductional division involves formation of daughter cells with half the number of chromosomes.

Solution 23:

  1. If four cells undergo mitosis, eight daughter cells will be produced.
  2. Sixteen daughter cells will be produced.
  3. Eight daughter cells will be produced if four cells undergo amitosis.

Solution 24:

  1. Mitosis
  2. ATP
  3. Homotypic
  4. Reduction
  5. Mitosis

Solution 25:

  1. Anaphase in a plant cell
  2. A – Spindle fibre
    B – Cell wall
  3. The homologous daughter chromatids or chromosomes begin to move towards opposite poles.
  4. This type of cell division occurs usually in the somatic cells.
  5. Two daughter cells are formed from this type of cell division.
  6. The dividing cell shown is a plant cell because of the presence of cell wall and the absence of centriole.

Solution 26:

  1. A – Duplicated chromosomes
    B – Centromere
  2. The structure C is Spindle fibre. Its function is to help in the movement of chromosomes.
  3. The type of cell division is mitosis because all chromosomes appear to be same as there is no crossing over.
  4. Metaphase.
  5. Prophase occurs before metaphase and after metaphase anaphase takes place

Solution 27:

  1. (c) Meiosis
  2. (a) Mitosis
  3. (c) Both of these
  4. (a) 1/2
  5. (b) Growth and repair
  6. (a) Movement of chromosomes
  7. (a) Meiosis
  8. (d) Both (a) and (c)
  9. (b) Chromatin
  10. (c) Both (a) and (b)
  11. (b) Metaphase
  12. (a) Meiosis I
  13. (d) One cell, two nuclei
  14. (a) Meiosis
  15. (d) Telophase
  16. (d) Prophase
  17. (c) Telophase

 

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