202110239-TRIUMPH-STUDENT-WORKBOOK-BIOLOGY-G09-PART1

1.3 Key Concepts i. Our sense organs namely eye, ear, nose, tongue and skin aid our survival by direct- ing us towards certain informations of our environment that are important for us and influence some activity known as stimulus. ii. Brain has the ability to use the information sensed by our sense organs to produce a rich sensory experience in a matter of milliseconds. iii. Response to all our experiences and feelings are a result of our nervous system which involve nerve signals. iv. Nerve signals play a very important role in the way we react or respond to various stimuli or even to same stimuli in different situations. v. Certain substances, conditions etc in nature trigger the process of sensing them by our body. These are called stimulants. vi. Organs called receptors present in our sense organs pick information carried by stim- ulants and convert them into nerve signals. vii. Nerve signals are carried to brain and processed to produce sensation. viii. The information through receptors reaches the brain through sensory nerves and the signals to show response reach the organ through motor nerves. ix. Sensory organs are considered as stimulus detectors which specialise in gathering information about new and changing events. 1.4 Conceptual Understanding Q1. Find whether the statement is true or false and rewrite the sentence correctly if it is false. [Refer to TB page 92]SecII, Q5) We are not able to adapt to sensations. A. False: We can adapt to sensations. Neurons involved with smell, hearing, taste, touch, and sight can all exhibit sensory adaptation. Q2. Choose the correct answers: [Refer to TB page 93]SecVI, Q2) Sensation is a complex pathway involving: (a) Sense organs (b) Sense organs and nerve impulses (c) Sense organs, nerve impulses, brain (d) Brain and nerve impulses A. (c) SESSION 1. INTRODUCTION, SENSES AND STIMULI 149

1.5 Appreciation and Aesthetic Sense, Values Q1. How would you pay concern towards disabled people who are lacking sensory organs? [Refer to TB page 93]QXI ) A. i. We all should extend our concern towards the people who have disabilities in their senses. ii. Disability in sense organs may lead to difficulty in seeing, or hearing, or smelling or eating or feeling. iii. We should help them in all their needs but should never make fun of such people. iv. Disability is something that is imposed on top of our impairments.They are unnec- essarily isolated and excluded from full participation in society. v. Disabled people are therefore considered an oppressed group in society. Their isolation and segregation in every area of life, such as education, work, mobility, housing, etc., should be avoided. vi. It is our responsibility to ensure that these people get both physical and social access to same spaces, offices, entertainment, goods and services. vii. They should be guaranteed physical assessibility and non–discrimination in em- ployment and delivery of goods, services, education etc. Q2. How do you appreciate the functions of sensory organs which help us to enjoy the beauty of nature?( [Refer to TB page 93]QXII ) A. i. We enjoy the beauty of nature with our eyes, the melodious music with our ears, the fragrance of flowers with our nose, the taste of food with our tongue and feel the cool breeze on our skin. All these situations show just how our senses pick up information and react to them. ii. Our senses are not just a part of us but they define us. All our experiences and feelings in life are possible only with the use of our senses. iii. Brain has the ability to use information sensed by our eyes, ears, skin, tongue, and nose to produce a rich sensory experience in a matter of milliseconds. iv. They aid our survival by directing us toward certain informations of our environment that are important for us and influence some activity. For example: Tasty food draw us towards them and our mouth starts watering. v. Our senses also help us to locate mates, seek shelters and recognise our friends. vi. Our senses also give us the opportunity to find pleasure in music, art, athletics etc. vii. They play a very important role in the way we react or respond to various stimuli or even to same stimuli in different situations. For example generation of flavour preferences by our brain is usually based on what our body needs. viii. Stimuli from the environment around are received by our body through sense or- gans. SESSION 1. INTRODUCTION, SENSES AND STIMULI 150

SESSION 2 EYE 2.1 Mind Map 2.2 Terminology i. Lachrymal glands – continually secrete tears which moisten, lubricate, and protect the surface of the eye. ii. Conjunctiva –is the mucous membrane that covers the front of the eye and lines the inside of the eyelids. iii. Sclera – is the outermost, thick, tough, fibrous, non–elastic and white–coloured layer of the eye that acts as a tough protection from injury, and provides attachment for the extraocular muscles that move the eye. iv. Choroid layer – is a thin, pigmented and highly vascular membrane of eye present between the sclera and the retina functioning to nourish the retina and absorb scattered light. v. Retina – is a thin layer of tissue that lines the back of the eye on the inside. It receives the light focused by the lens, convert it into neural signals, and send these signals on SESSION 2. EYE 151

to the brain for visual recognition. vi. Cornea – is the transparent front part of the eye formed by bulging of sclera that covers the iris, pupil, and anterior chamber. vii. Pupil – is a hole located in the center of the iris of the eye that allows light to strike the retina. viii. Iris –is the part formed by the choroid layer around the pupil in which radial and circular muscles are present. ix. Suspensory ligaments – of the eye are ligaments that attach the ciliary body to the lens of the eye. x. Vitreous chamber –is the part of the inner eye ball which is filled with jelly–like fluid. xi. Aqueous chamber – is the part of the inner eye ball which is filled with water–like fluid. xii. Blind spot –is the area of no vision lacking light–detecting photoreceptor cells. xiii. Fovea –Also called as Yellow spot or Macula, it is the area of best vision containing the largest concentration of cone cells in the eye. xiv. Photoreceptors –are specialised light–sensitive cells that absorb light energy and respond by creating nerve impulses. xv. Optic nerve –All the nerve cells bundled together form the optic nerve which trans- ports the visual information from eye to the brain. xvi. Night blindness – is the inability of the eye to see well at night or in poor light. It is a symptom of untreated nearsightedness. xvii. Myopia –or near sightedness is a vision condition in which close objects are seen clearly, but objects farther away appear blurred. xviii. Hypermetropia –or long–sightedness or far–sightedness is the condition in which far objects are seen clearly, but objects kept close appear blurry. xix. Cataract – is clouding of the lens in the eye leading to a decrease in vision. xx. Colour blindness – is the inability or decreased ability to see color, or perceive color differences, under normal lighting conditions. 2.3 Key Concepts i. Eyes provide vision which helps us to detect desired targets, threats and changes in our physical environment and to adapt accordingly. ii. Eyes contain eye lids, eye lashes, eye brows and lachrymal glands. iii. Conjunctiva membrane covers the front portion of the eye. iv. Eye has three main layers–sclerotic layer or sclera, choroid layer and retina. v. The eyes has a biconvex lens which forms an inverted image on the retina at the back of the eye. vi. Suspensor ligaments help in adjusting the focal length of the eye lens. vii. Iris patterns are individual specific. viii. Retina contains photoreceptors called rods and cones. SESSION 2. EYE 152

ix. Rods contain a pigment called rhodopsin which helps us see in dark; cones contain the pigment iodopsin which help us see during bright light. x. Area of no vision is called blind spot and area of best vision is called yellow spot. xi. Yellow spot is also called fovea or macula. xii. Nerve cells in the eye make up the optic nerve which carries visual information from the eye to the brain. xiii. The point at which the optic nerve exits the eye is called blind spot. xiv. Night blindness, xerophthalmia, cataract, myopia and hypermetropia are some of the diseases associated with eyes. 2.4 Conceptual Understanding Q1. Give reasons for: We usually do not see bright colours in dim light. [Refer to TB page 92 ]Section I, Q1) A. i. Retina has two types of cells — rods and cones. ii. Rods have the pigment rhodopsin which helps us to see in dark or dim light. iii. It detects only low intensities of light and cannot make distinctions that give rise to our sensation of colours. iv. So we can’t see bright colours in dim light. Q2. While cutting onions our tears start flowing. [Refer to TB page 92]Section I, Q4) A. i. When an onion is cut, some amino acids are released into the air. ii. Enzymes convert these amino acids into lachrymator compounds (irritants). iii. This irritates the nerves around the eyes and stimulate lachrymal glands to produce tears. Q3. Find whether the statement is true or false and rewrite the sentence correctly if it is false. The rationale behind seeing is just the impression of the image in the retina. ( [Refer to TB page 92]Sec II, Q1) A. False. The rationale behind seeing is the ability of the eyes to take the information from light waves, then transform the characteristics of light into neural signals that the brain can process. SESSION 2. EYE 153

Q4. Iris patterns are like finger prints used in identifying individuals (True / False). ( [Refer to TB page 9 Q2]Sec II, Q3) A. True Q5. State the differences between the two: ( [Refer to TB page 92]SecIII, Q1 and 2) A. 1. Rods and cones SN Rods Cones 1 Rods help us to see in Cones help us to see in bright light. dark. 2 These contain the They contain the pigment pigment rhodopsin. iodopsin. 3 They detect low They detect bright intensities of light. colours of light. 4 Fine distinction of colours Fine distinction of colours cannot be made. is detected. 2. Iris and Pupil SN Iris Pupil 1 Iris is the coloured part of Pupil looks like a black the eye, which is typically dot at the centre of the black or brown. iris. 2 The size of iris does not The size of the pupil change. changes depending on the brightness of the light. 3 Iris is a patch of tissue. Pupil is a gap in the tissue. SESSION 2. EYE 154

Q6. How do the following processes occur?( [Refer to TB page 92]Sec IV, Q1) When we see an object, a real inverted image is formed on the retina. A. i. A biconvex lens is present behind the pupil in the eye. ii. The eye has a unique ability to take information from light waves and transform it into neural signals which the brain processes. iii. The eye gathers light through the convex lens, focuses it, and forms an image on the retina at the back of the eye. iv. The lens turns the image left to right and upside down as a convex lens forms an inverted image only. v. This visual reversal influences the very structure of the brain, which tends to main- tain this reversal in its sensory processing regions. vi. Thus, most information from the sense organs crosses over to the opposite side of the brain. vii. Likewise, “maps” of the body in the brain’s sensory areas are typically reversed and inverted. viii. The eye forms an image that gets extensive further processing in the brain. Q7. Fill in the blanks with suitable words. Then give reasons why the words are suitable. ( [Refer to TB page 92]SecV, Q1,3) (Pg 93 ; TB Sec V, Q4) A. i. Choroid layer provides oxygen to the eye. (It contains a lot of blood vessels and so provides oxygen to the eye) ii. Iris pattern is used for individual identification. (Iris patterns are individual specific and so are used for individual identification) iii. Area where optic nerve leaves the eye is called the blind spot. (No image forma- tion takes place at this point) Q8. Choose the correct option( [Refer to TB page 9 Q3]Sec VI, Q1) This vitamin is essential for the health of eye. a) Vitamin A b) Vitamin B c) Vitamin C d) Vitamin D A. (a) Vitamin A SESSION 2. EYE 155

Q9. The muscles of the eyeball of a person becomes non functional, the invariable effect would be ( [Refer to TB page 93]Sec VI Q4) (a) The person fails to close eyes (b) Fails to move eye and see colours clearly (c) Feels pain in the eye (d) The nerves reaching the muscles become non functional. A. (b) Fails to move eye and see colours clearly 2.5 Information Skills and Projects Q1. Form a group with five students in your class and collect eye diseases and its charac- teristics by talking with ophthalmologist assistant. [Refer to TB page 93]QIX) A. Student’s Activity Hints: i. Glaucoma–increased pressure of the fluid inside the eye causes optic nerve dam- age and ultimately causes blindness. ii. Dry Eye Syndrome–this syndrome occurs due to problem with the tear ducts or eyelids. This condition can cause pain and blurry vision. iii. Colour blindness–it is colour vision deficiency. Most common colour blindness is the blue–green–red colour blindness, where a person is unable to distinguish between blue, green and red colours. iv. Night blindness – caused due to deficiency of Vitamin A. v. Far–sightedness or Hypermetropia vi. Near–sightedness or Myopia 2.6 Communication Through Drawing and Model Making Q1. Draw and label a diagram showing the structure of the eye. [Refer to TB page 93]Sec X, Q1) SESSION 2. EYE 156

A. SESSION 2. EYE 157

SESSION 3 EAR, NOSE, TONGUE AND SKIN 3.1 Mind Map SESSION 3. EAR, NOSE, TONGUE AND SKIN 158

3.2 Terminology i. Pinna –is the visible flap–like structure of the ear on either side of our head. ii. Ceruminous glands –are wax–producing glands present inside the pinna. iii. Sebaceous glands – are oil–producing glands present inside the pinna. iv. Auditory meatus –or the ear canal is a tube running from the outer to the middle ear leading to the eardrum. v. Malleus –is the first bone of the middle ear connected to the narrow area of the ear–drum. vi. Incus –is a small anvil–shaped bone in the middle ear, transmitting vibrations be- tween the malleus and stapes. vii. Stapes – is the innermost bone in the middle ear which is involved in the conduction of sound vibrations to the inner ear. viii. Tympanum –or the ear–drum is a cone–shaped thin layer present at the end of the auditory meatus between middle and external ear. ix. Vestibule – is the central part of the membranous labyrinth situated medial to the tym- panic cavity, behind the cochlea, and in front of the semicircular canals. x. Semilunar canals – are three tiny, fluid–filled tubes in our inner ear that help us keep our balance. xi. Cochlea –is a spiral–shaped structure that translates sound into nerve impulses to be sent to the brain. xii. Vestibular apparatus –The vestibule and the semilunar canals together comprise the vestibular apparatus. xiii. Basilar membrane –separates the second and third parallel tubes scala media and scala tympani of the cochlea. SESSION 3. EAR, NOSE, TONGUE AND SKIN 159

xiv. Auditory nerve –which is formed by joining together of the vestibular and cochlear nerves transmits sound and equilibrium (balance) information from the inner ear to the brain. xv. Chemoreceptors – is a sensory receptor that detects certain chemical stimuli in the environment. xvi. Olfactory sensation –is the sense of smell that results when olfactory receptors in the nose are stimulated by particular air–borne chemical molecules. xvii. Fungiform papillae –are the roundish structures present on our tongue. xviii. Filiform papillae –are the flake–like structures present on our tongue. xix. Circumvallate papillae – are the large roundish structures present on the back of our tongue. xx. Foliate papillae – are the bump–like structures present on the sides of our tongue. xxi. Taste pore –Each taste bud has a cavity with a pore called as taste pore. xxii. Melanin –is the pigment responsible for colour of the skin. It gets stimulated by sunlight and turns the skin dark to protect other layers of the skin from harmful effects of sunlight. xxiii. Cutaneous receptors – are receptors present in the skin which are sensitive to touch or any other stimulus affecting the skin. xxiv. Tactile receptors –are receptors present in the skin which are sensitive to touch. xxv. Pacinian corpuscles – are receptors present in the skin sensitive to pressure. xxvi. Nociceptors – are receptors present in the skin sensitive to changes in temperature. xxvii. Leucoderma –is a skin disease caused due to deficiency of melanin. 3.3 Key Concepts Ear: i. External ear is called pinna. ii. Ear canal is called auditory meatus. iii. Ear drum called tympanum is present at the end of auditory meatus. iv. Pinna has ceruminous and sebaceous glands which keep the ear canal lubricated. v. Middle ear has 3 bones — malleus, incus and stapes. vi. They amplify the sound vibrations received on the tympanum membrane. vii. Internal ear consists of bony labyrinth enclosing the membranous labyrinth. viii. Vestibular apparatus maintains the equilibrium of the body. ix. Cochlea is a spiral shaped structure in the internal ear. x. The cochlear fibres form the cochlear nerve which joins the vestibular nerve to form the auditory nerve. xi. The auditory nerve sends the impulses to the brain for processing. SESSION 3. EAR, NOSE, TONGUE AND SKIN 160

Nose: i. Sense of smell serves a protective function by sensing the odour of possibly danger- ous food, or predator for some animals. ii. External nose has 2 nostrils which lead to the nasal cavity. This cavity is divided into two halves by a nasal septum. iii. The hair and mucous in the nasal cavity stops the entry of dust and germs from gaining entry into the nose. iv. Nasal receptors or the olfactory receptors present in the membrane of nasal cavity sense the shape of odour molecules. v. These receptors transform the information about the stimulus into neural signals which are sent to sensory centre of the brain for further processing. vi. There is a connection between smell and the taste and humans use the two in con- junction to locate, identify and avoid spoiled food etc Tongue: i. Tongue is made up of a voluntary muscle and is attached at one end. ii. It contains nearly 10,000 taste buds located in the walls of papillae. iii. Filiform papillae (flake–like structures), Fungiform papillae (round structures), Circumvallate papillae (large round structures at the back), and foliate papillae (bump–like structures on the sides) of the tongue are the four types of papillae on which taste buds are lo- cated. iv. The taste receptors present in the taste buds sample flavours from different food and drinks consumed by us. v. The information or taste messages are sent to specialised regions of brain by a spe- cialised nerve “hotline”. vi. A same taste bud is capable of producing different signals corresponding to different chemicals in food. Skin: i. Skin is the outermost covering of our body and regulates body temperature. It also helps to eliminate waste materials through sweat. ii. Skin is the organ of touch. It has cutaneous receptors. iii. Skin has 2 layers — epidermis and dermis. iv. Epidermis has sweat pores and small hairs. v. Epidermis consists of 3 layers — cornified layer, granular layer and malpighian layer. vi. Dermis lies below the epidermis and possesses sweat glands, sebaceous glands, hair follicles, blood vessels and fat. vii. Colour of the skin is due to a pigment called melanin. viii. Skin contains tactile receptors for sensing touch, pacinian corpuscles for pressure, nociceptors for temperature etc. ix. Viral diseases such as measles, chicken pox etc; bacterial diseases such as leprosy; SESSION 3. EAR, NOSE, TONGUE AND SKIN 161

fungal disease such as ring worm; vitamin deficiency disease such as pellagra are some skin diseases which affect the skin. x. Leucoderma is the disease that is caused due to deficiency of melanin. 3.4 Conceptual Understanding Q1. Give reasons for: Removal of wax layer too often will raise incidence of ear infection. (Pg 92, Section I, Q2) A. i. Wax produced by ceruminous gland in the external ear keep the ear canal lubri- cated. ii. It also prevents the entry of dust and other unwanted irritants in our ears. iii. Moreover, excessive cleaning by scraping with an ear–bud might damage the out- ermost layer of ear canal causing minor injury. iv. Due to all these reasons, it is apt to say that removing wax layer will increase the chances of ear infection. Q2. During severe cough and cold we lose taste of food. (Pg 92, Section I, Q3) A. i. Like smell, taste is also a sense based on identifying chemicals in food and the texture of it. ii. The senses of taste and smell have a close and cooperative working relationship. iii. Many of the subtle distinctions we think of as flavours really come from odours. iv. So, when we have cold, our sense of smell will get affected and the food will seem tasteless as we cannot sense the odours. Q3. Find whether the statement is true or false and rewrite the sentence correctly if it is false. Ear functions only to hear. (Pg 92, Section II, Q2) A. False. Ears not only function to hear but also helps in maintaining equilibrium or balance in the body. Q4. Saliva helps the taste buds in taste sensation. (Pg 92, Section II, Q4) A. True SESSION 3. EAR, NOSE, TONGUE AND SKIN 162

Q5. State the difference between the two: (Pg 92, Section III, Q3, Q4) A. Pinna and Tympanum SN Pinna Tympanum 1 It is the external ear. Ear canal in the external ear leads to the eardrum, also called as tympanum. 2 It is the visible part. It is not visible. Nasal cavity and Ear canal SN Nasal Cavity Ear Canal 1 Externally, the nostrils External ear leads into the lead into nasal cavity auditory meatus, also present in the nose called as ear canal. 2 Olfactory receptors are Auditory receptors are present. present. Q6. How do the following processes occur? The sound waves, collected by the pinna are changed as vibrations. (Pg 92, Section IV, Q2) A. i. External ear or pinna collects the sound waves from where they enter into the auditory meatus. ii. From there, they strike the tympanum from where they are transferred to the middle ear to the malleus, incus and stapes. iii. The middle ear magnifies the intensity of the sound vibrations. iv. Through the oval window, the vibrations reach the cochlea in the inner ear and the impulses are sent to the brain through the auditory nerve. Eventually, according to the responses given by the brain, the hearing can be done. SESSION 3. EAR, NOSE, TONGUE AND SKIN 163

Q7. We move our hand away from a hot object. (Pg 92, Section IV, Q3) A. i. Our skin is the sense organ for touch. ii. It contains cutaneous receptors for touch. iii. When we touch a hot object, the cutaneous receptors in the skin send the impulse to our spinal cord. iv. A reflex arc is formed and it sends information to the muscle in the hand to withdraw. Q8. A pungent odour makes us close our nose. (Pg 92, Section IV, Q4) A. i. Whenever our nose receives a pungent smell, olfactory receptors present in the nose send a signal to brain via olfactory nerve. ii. The brain interprets these signals and in turn, sends signals to the nerves of the nose to close, thus stopping the nose from breathing in more of the pungent smell. iii. Due to this reason, we tend to cover our nose or pause our breath for a while to avoid smelling pungent odour. Q9. Fill in the blanks with suitable words. Then give reasons why the words are suitable. [Refer to TB pages 92, 93], Section V, Q2, Q5) A. i. The relationship between the tongue and nose has close association. (Reason: Without smell, taste of food cannot be enjoyed). ii. The ear drum is the tympanum. (Reason: Sound waves enter the ear canal and strike the tympanum or the ear–drum). Q10. The sound waves if not focused by external pinna and ear canal will result in (Pg 93, Section VI, Q3) (a) Hearing several types of sound loudly (b) not hearing anything (c) Slight hearing (d) not being able to make out the type and origin of sound A. (c) SESSION 3. EAR, NOSE, TONGUE AND SKIN 164

Q11. Choose the correct option. (Pg. 93, Section VI, Q5) The tongue of a person is exposed to a high salty taste, then: a) The person learns to taste salty things better b) Loves tasting salty things c) Hates tasting salty things d) Fails to taste a less salty thing just after the exposure A. d) Fails to taste a less salty thing just after the exposure 3.5 Asking Questions and Making Hypothesis Q1. What happens if our skin loses its sensory nature? ( [Refer to TB page 93]QVII) A. i. Our skin acts as a protective barrier between our internal body systems and the outside world. ii. It is the sense organ for touch and contains cutaneous receptors for sensing touch stimulus. iii. It consists of two main layers–Epidermis and Dermis, of which the epidermis con- tains hair and sweat pores and is the layer for protection. iv. Dermis is made up of connective tissue and contains sweat glands, sebaceous glands, hair follicles, blood vessels and fat. v. It provides first level of protection to the body. vi. It regulates body temperature and eliminates certain waste materials through sweat. vii. The melanin present in our skin protects us from harmful effects of the Sun radia- tions. viii. Its ability to perceive touch sensations gives our brain wealth of information about the environment around us, such as temperature, pain, and pressure. ix. Without our sense of touch, it would be very hard to get around in this world. It is truly amazing how much information we receive about the world through our sense of touch. 3.6 Communication Through Drawing and Model Making Q1. Draw and label the diagrams, showing the structure of the a) Ear; b) Tongue ( [Refer to TB page 93]QX –2,3) SESSION 3. EAR, NOSE, TONGUE AND SKIN 165

A. a) Ear – b) Tongue – 3.7 Application to Daily Life, Concern to Bio Diversity Q1. Sagar is not able to listen properly. Guess what would have happened to him. What suggestions you would like give to him? ( [Refer to TB page 93]QXIII) SESSION 3. EAR, NOSE, TONGUE AND SKIN 166

A. i. If Sagar is not able to listen properly, he might be suffering from an ear disease or infection. ii. If the external ear and auditory meatus are unable to focus the sound waves prop- erly, we are able to hear the sound very slightly. iii. Infection in the middle ear will not cause proper magnification of the sound waves. iv. We would like him to clean his ear properly to check over accumulation of wax and consult an ENT specialist if the problem persists. —— CCE Based Practice Questions —— AS1-Conceptual Understanding Very Short Answer Type Questions 1. State true or false. [Refer to Session 6.3 ] (i) If any blockage occurs due to ear wax, we should pour boiled coconut oil to loosen it. [] (ii) We should wash nostrils with lukewarm salt water. [] (iii) We should clean and wash the tongue before going to bed at night and after rising up in the morning. [] (iv) We should always keep ourselves clean by bathing twice a day to avoid skin infections. [] (v) Taking care of sense organs is necessary for good health. [ ] 2. Answer the following questions in one sentence. [Refer to Session 6.3 ] (vi) Why do babies and infants try to sense everything by taste? CHAPTER 6. SENSE ORGANS 167

(vii) Which flavour is associated with monosodium glutamate? (viii) Which layer of skin helps in protection? (ix) Name the disease which occurs because of the deficiency of melanin. (x) What are the tactile receptors present on the skin used for? 3. State true or false. 168 [Refer to Session 6.2 ] CHAPTER 6. SENSE ORGANS

(xi) We should not rub our eyes if anything falls in them. [ ] (xii) Myopia means far sightedness. [ ] (xiii) The lens in our eyes are biconcave and crystalline in nature. [ ] (xiv) Lachrymal glands produce tears. [ ] (xv) The optic nerve carries light for vision to brain. [ ] 4. Fill in the blanks. [Refer to Session 6.2 ] (xvi) Aqueous chamber is filled with . (xvii) The area of no vision is called the and the area of best vision is called the . (xviii) Only portion of the eye ball is visible to us. (xix) The real work in the retina is performed by light–sensitive cells known as . (xx) and length of the eye lens. are capable of adjusting the focal 5. Which organ do we appreciate for each of the following functions? [(Session 6.1)] CHAPTER 6. SENSE ORGANS 169

Column A Column B i. For feeling cool breeze a. Tongue ii. For enjoying melodious music b. Skin iii. For enjoying fragrance of flowers c. Eyes iv. Enjoying beauty of nature d. Ears v. For tasting delicious cuisines e. Nose 6. Fill in the blanks. [Refer to Session 6.1 ] (xxi) from the environment are received by the sense organs. (xxii) Sense organs have which can recognize specific stimuli. (xxiii) is the centre for all the sensitive activities. (xxiv) Changes in the stimulus if they are not of a particular level. (xxv) Sensation is a complex pathway involving sense organs, and brain. Short Answer Type Questions 7. Answer the following questions in 3-4 sentences. (i) [(Session 6.3)] What do you know about the middle ear? CHAPTER 6. SENSE ORGANS 170

(ii) [(Session 6.3)] What do you know about skin? 8. Answer the following questions in 3-4 sentences. (i) [(Session 6.2)] Why does our pupil enlarge when we go to the cinema hall? (ii) [(Session 6.2)] What are rods and cones? 171 CHAPTER 6. SENSE ORGANS

(iii) [(Session 6.2)] Why the lines in the given image, though straight, appear crooked? What do you understand by this? 9. Answer the following questions in 3-4 sentences. (i) [(Session 6.1)] What are sensory receptors? CHAPTER 6. SENSE ORGANS 172

(ii) [(Session 6.1)] What are the functions of sense organs? Long Answer Type Questions 10. Answer the following questions in 6-8 sentences. (i) [(Session 6.3)] How can we hear sounds? How does the ear function? CHAPTER 6. SENSE ORGANS 173

11. Answer the following questions in 6-8 sentences. (i) [(Session 6.2)] How does the eye protect itself? AS2-Asking questions and making hypothesis Short Answer Type Questions 12. Answer the following questions in 3-4 sentences. (i) [(Session 6.1)] Write the consequences of what happens if receptors are not present in our sense organs? CHAPTER 6. SENSE ORGANS 174

Long Answer Type Questions 13. Answer the following questions in 6-8 sentences. (i) [(Session 6.3)] After a lesson on skin by your teacher, you still have questions in your mind. What questions would you ask to clarify them? AS3-Experimentation and field investigation Long Answer Type Questions 14. Answer the following questions in 6-8 sentences. (i) [(Session 6.3)] How can you experimentally show that sound has energy? CHAPTER 6. SENSE ORGANS 175

AS4-Information skills and projects Short Answer Type Questions 15. Answer the following questions in 3-4 sentences. (i) [(Session 6.2)] Observe the diagram given below and answer the following questions. i. What are the functions of pupil? 176 ii. Name two diseases associated with eyes? iii. How can we take care of our eyes? CHAPTER 6. SENSE ORGANS

Long Answer Type Questions 16. Answer the following questions in 6-8 sentences. (i) [(Session 6.3)] Collect information on the different human races. Prepare a report on it. AS5-Communication through drawing and model making Long Answer Type Questions 17. Answer the following questions in 6-8 sentences. (i) [(Session 6.3)] Label the given parts: CHAPTER 6. SENSE ORGANS 177

AS6-Appreciation and aesthetic sense, Values Short Answer Type Questions 18. Answer the following questions in 3-4 sentences. (i) [(Session 6.3)] When Ananya found out that there is hair and mucous present in our nasal cavity, she thought that was disgusting. But her science teacher explained that they have an important function. What is it? (ii) [(Session 6.3)] Ajay was surprised to learn about taste buds. How do they work? CHAPTER 6. SENSE ORGANS 178

Long Answer Type Questions 19. Answer the following questions in 6-8 sentences. (i) [(Session 6.1)] How do you appreciate the functions of sense organs? AS7-Application to daily life, concern to bio diversity Short Answer Type Questions 20. Answer the following questions in 3-4 sentences. (i) [(Session 6.3)] How should an individual take care of their skin? CHAPTER 6. SENSE ORGANS 179

(ii) [(Session 6.3)] How should we take care of our ears? 21. Answer the following questions in 3-4 sentences. (i) [(Session 6.2)] Why did government take a photo of your eye for issuing AADHAR card? Objective Questions AS1-Conceptual Understanding 22. Choose the correct answer. (i) The aperture controlling the amount of light entering the eye is called (A) The lens (B) The pupil (C)The ciliary muscles (D) Cornea CHAPTER 6. SENSE ORGANS 180

(ii) Which of these sense organs have a capability of maintaining body’s equilibrium, pertaining to the posture and balance of the body? (A) Ears (B) Eyes (C) Nose (D) Skin (iii) The fovea is the part of the retina that contains photoreceptors called (A) Rods (B) Cones (C)Ganglion cells (D)Amacrine cells (iv) Which part of ear collects sound waves? (A) Auditory meatus (B) Tympanum (C) Pinna (D)Ear drum (v) John Dalton suffered from a type of colour blindness where the green pigment is missing in the cones of the eyes. What is this type of colour blindness called? (A) Tritanopia (B) Achromatopia (C) Deuteranopia (D) Protanopia (vi) Which part of ear plays an important role in amplifying the vibrations received on the tympanum membrane? (A) External ear (B) Middle ear (C)Internal ear (D)None of the above (vii) Yellow spot in the retina is also known as (A) Macula (B) Cornea (C) Fovea (D)Both A and C (viii) When we cannot smell (A) We cannot identify the taste of food (B) We cannot respire (C)We cannot have infections CHAPTER 6. SENSE ORGANS 181

(D)Nothing will happen (ix) Which cells in the eye make up the optic nerve and carry the information to the brain? (A) Nerve cells (B) Neuron (C)Cone cells (D)Both A and B (x) Unlike other senses, smell signals are not relayed through (A) Hypothalamus (B) Spinal cord (C) Brain (D) Nerves (xi) The membrane which separates semi linear canals and cochlea is the (A) Basilar membrane (B) Basement membrane (C)Plasma membrane (D)Semi–permeable membrane (xii) Yellow spot and blind spot are present on the (A) Cornea (B) Retina (C) Fovea (D) Stapes (xiii) The small black round area in the middle of the eye which allows light in is called (A) Sclera (B) Iris (C) Pupil (D) Fovea (xiv) Which of the following are bones present in the ear? (A) Malleus (B) Incus (C) Stapes (D)All of these (xv) Which of the following pigments is responsible for the colour of skin? (A) Keratin (B) Chitin (C) Melanin (D) Chlorophyll (xvi) This is the area of no vision in retina. CHAPTER 6. SENSE ORGANS 182

(A) Yellow spot (B) Blind spot (C) Myopia (D) Fovea (xvii) How many taste buds are present on the tongue? (A) 100 (B) 1,000 (C) 10,000 (D) 5,000 (xviii) Which of the following is the largest sense organ in humans? (A) Eye (B) Heart (C) Ear (D) Skin (xix) Which of the following diseases affect skin? (A) Measles (B) Leprosy (C) Leucoderma (D)All of these (xx) What are the receptors for touch present in skin called? (A) Tactile (B) Pavilion (C) Nocireceptors (D)All of these CHAPTER 6. SENSE ORGANS 183

7. ANIMAL BEHAVIOUR SESSION 1 INTRODUCTION, TYPES OF ANIMAL BEHAVIOUR AND HUMAN BEHAVIOUR 1.1 Mind Map 1.2 Terminology i. Animal behaviour –Animal behaviour is the scientific study of the wild and wonderful ways in which animals interact with each other, with other living beings and with the environment. ii. Reflex –A reflex action, differently known as a reflex, is an involuntary and nearly instantaneous movement in response to a stimulus. iii. Instinct – Instinctual behaviours are the one that need not to be learned. iv. Imprinting –Imprinting is a type of behaviour where ducklings and chicken recognize their mother. They follow the first moving object they see after hatching. v. Conditioning –Conditioning is a type of behaviour involving a resposne to a stimulus that is different from natural one. It is a type of learned behaviour. vi. Imitation –Imitation is the behaviour where one animal copies the other animal. SESSION 1. INTRODUCTION, TYPES OF ANIMAL BEHAVIOUR AND HUM... 184

1.3 Key Concepts i. Several types of behaviours are seen in humans and other animals. ii. These may be finding food resources, defending themselves from predators, choosing mates, building nests, hiding food, taking care of young ones etc. iii. The behaviours studied are — instinct, imprinting, conditioning and imitation. iv. Reflex is a type of instinct behaviour. v. Imprinting is a type of behaviour where ducklings and chicken recognize their mother. They follow the first moving object they see after hatching. vi. Conditioning is a learned behaviour. vii. Ivan Pavlov, a Russian scientist investigated on conditioning. viii. Imitation is the behaviour where one animal copies the other animal. ix. Human beings also exhibit instinct, imitation and conditioning behaviours. x. But human behaviour is complex than animals as we can control our emotions and be aware of goods and bads. 1.4 Conceptual Understanding Q1. What is the advantage of reflex action? [Refer to TB page 104 Q1] (a) It has to be learned (b) It happens differently each time (c) It does not have to be learned (d) None of them A. (c) It does not have to be learned Q2. If a rat is given a mild electric shock when it is going to a certain part of its cage, it eventually avoids going there. This is because of [Refer to TB page 104 Q2] (a) Imitation (b) Conditioning (c) Instinct (d) Imprinting A. (b) Conditioning SESSION 1. INTRODUCTION, TYPES OF ANIMAL BEHAVIOUR AND HUM... 185

Q3. Describe all four types of behaviours discussed in the lesson with appropriate examples. [Refer to TB page 104 Q3] A. The four types of behaviours discussed in this lesson are: i. Instinct ii. Imprinting iii. Conditioning and iv. Imitation i. Instinct: The behaviours that need not be learned are called instinctual be- haviours. E.g. – i. Making nests by birds, choosing mates and forming of groups for protection from predators etc. ii. Spinning of web by a spider is an instinctual behaviour as no one teaches it to spin the web and it spins for its own protection. iii. If we touch something too hot or too sharp, we automatically remove our hand. This is because of reflex which is also an instinctual behaviour. ii. Imprinting: Chickens and ducklings can walk as soon as they are hatched. Ducklings can even swim within a few days. They follow the first moving object they see after they are hatched. With this type of behaviour they can recognise their mother. Such type of behaviour is called imprinting. Imprinting is nothing but learning behaviour. iii. Conditioning: The type of behaviour which involves the response to the stimulus that is different from the natural one is conditioning. It is also a type of learned behaviour. E.g. Children show different responses to school bell as per the time. Ivan Pavlov experimented on dog regarding conditional behaviour. He gave the dog its food and at the same time rang a bell. The dog would listen to the bell and start producing saliva. He continued this for several days and then rang the bell without giving food, even then dog started salivating. The salivation in dog on hearing the bell is not a natural response but the scientist conditioned it to do so. iv. Imitation: Imitation is the type of behaviour where one animal copies the other. This was thought to be seen in humans only. But later scientists observed that animals too imitate. E.g. Chimpanzees and other primates imitate each other. Chimpanzees use sticks to spear juicy grubs and eat them. Other chimpanzees copy this behaviour and learn new skills. Q4. Differentiate between [Refer to TB page 104 Q4] A. a) Imitation and Imprinting SESSION 1. INTRODUCTION, TYPES OF ANIMAL BEHAVIOUR AND HUM... 186

SN Imitation Imprinting 1 Imitation is nothing but Imprinting is learning from copying from other their parents. animals. 2 Chimpanzees imitate other In this type of behaviour, chimpanzees. ducklings and chicken follow the object they first see after they are hatched. It may be any moving object and need not be any animal. b) Instinct and conditioning SN Instinct Conditioning 1 Instinctual behaviour is Conditional behaviour that which need not be involve a response to learned. stimulus which is different from natural one. 2 This occurs without much In this type of behaviour, thinking, just a reflex the animal is to be action. conditioned to do so. 3 It occurs all of a sudden. It takes time for conditioning. 4 E.g.: Removing a hand E.g., cattle grazing at a when we touch a sharp particular point of a fence object, closing our eyes if it gets an electric shock when bright light is repeatedly, it stops grazing focused are examples of at that point. instinct behaviour SESSION 1. INTRODUCTION, TYPES OF ANIMAL BEHAVIOUR AND HUM... 187

Q5. How is the behaviour of humans different from behaviour of other animals? Explain with an example. [Refer to TB page 104 Q5] A. i. Behaviour of humans is the same as the behaviour of other animals. But at the same time humans are certainly very different from that of other animals. ii. In a way human behaviour is often more complex. The reason behind this is we are comparatively more intelligent and aware of ourselves. iii. Humans have instincts, imitation and conditioning behaviour. But it is possible for us to overcome our natural urges and follow some type of behaviour. iv. E.g. Hungry person might want to eat something immediately after he sits at his dinner table but the manners he learnt will make him wait until everyone is seated and ready to eat. v. Young people may imitate someone they see daily and start drinking alcohol, smoking etc. 1.5 Asking Questions and Making Hypothesis Q1. Give two examples of reflexes? (Pg 95) A. i. Watering of mouth when we see a tasty substance or a food that we like the most is a type of reflex. ii. Students going to a classroom when the bell rings in school. Q2. Try to find more examples of imprinting. (Pg 95) A. i. Ducks imprint upon obvious stimulus such as ducks, other birds, people, flashing lights etc. and follow this stimulus for their early development. ii. Finches will imprint upon the birds they are raised with during their first weeks of development. SESSION 1. INTRODUCTION, TYPES OF ANIMAL BEHAVIOUR AND HUM... 188

1.6 Experimentation and Field Investigation Q1. What is going on in this figure? (Pg 96) A. Spider is spinning a web. Q2. Will you consider spinning the web by spider as an instinct behaviour? Why or why not? A. Yes, spinning the web by a spider is an instinct behaviour. Instinctual behaviours are behaviours that need not be learned. SESSION 1. INTRODUCTION, TYPES OF ANIMAL BEHAVIOUR AND HUM... 189

SESSION 2 INVESTIGATING BEHAVIOUR 2.1 Mind Map 2.2 Terminology i. Investigating behaviour – Behaviour can be investigated in the field or in the labora- tory. It can be observed, measured and experiments can be designed to test how it works. ii. Tagging – Animals are tagged by attaching tracking devices to them. Tagging lets scientists follow the journeys the animal make. iii. Pheromones –A pheromone is a chemical an animal produces which changes the behavior of another animal of the same species (animals include insects). iv. Intellectual ability – It is defined as the capacity to take in, compare, and recall data. 2.3 Key Concepts i. Tagging animals allow scientists to follow the journeys of animals as a part of migra- tion. SESSION 2. INVESTIGATING BEHAVIOUR 190

ii. Tagging is also one of the ways to study animal behaviour. iii. Tagging is usually done by using tagging devices such as lights etc. iv. Identifying or smelling ability of dogs and communicating nature in ants is because of pheromones. 2.4 Information Skills and Projects Q1. Observe ants going in a line. Ask your teacher how they communicate and write a note on this. [Refer to TB page 104 Q6] A. i. Ants going in a line, communicate with each other by using pheromones, sounds and touch. The use of pheromones as chemical signals is more developed in ants. ii. Ants perceive smell with their long,thin and mobile antennae. iii. The paired antennae provide information and direction of scents and pheromones. iv. Ants leave pheromone trails that may be followed by other ants to reach sources of food or their colonies. SESSION 2. INVESTIGATING BEHAVIOUR 191

SESSION 3 ANIMAL INTELLIGENCE 3.1 Mind Map 3.2 Terminology i. Intelligence –Intelligence has been defined in many different ways including one’s capacity for logic, abstract thought, understanding, self–awareness, communication, learning, emotional knowledge, memory, planning, creativity and problem solving. ii. Training –The action of teaching a person or animal a particular skill or type of be- haviour. iii. Code language –A code language is a code that assigns letters or numbers as identi- fiers or classifiers for languages. iv. Whistle –A clear, high–pitched sound made by forcing breath through a small hole between partly closed lips, or between one’s teeth. v. Hydroquinone –A crystalline compound made by the reduction of the chemical called benzoquinone. vi. Hydrogen peroxide –A colourless viscous unstable liquid with strong oxidizing prop- erties, used in some disinfectants and bleaches. SESSION 3. ANIMAL INTELLIGENCE 192

vii. Ethology – The scientific study of animal behaviour is called ethology. 3.3 Key Concepts i. Not only humans, but animals can also bluff, cheat or show self–consciousness. ii. Such a behaviour in animals is called animal intelligence. iii. Squirrels and Scrubjay hide their food from other animals by bluffing. iv. A scientist Hermon proved that dolphins can remember their names and understand a code language if they are well trained. v. Dutch biologist Nicholas Tinbergen and Austrian biologists Konrad Lorenz and Kar- lvon Frisch won a Nobel Prize in 1973 for their research on animal behaviour. 3.4 Appreciation and Aesthetic Sense, Values Q1. Understanding of animal behaviour creates positive attitude towards animals. How do you support this statement ? Explain with suitable examples. [Refer to TB page 104 Q7] A. i. We can certainly support this statement – “Understanding animal behaviour cre- ates positive attitude towards animals.” The greater the knowledge of animal be- haviour the greater will be the predictability of animal’s response. ii. The main objective to have positive attitude towards animals creates more aware- ness regarding our actions towards animals. iii. It brings about change in people and reminds them to be more compassionate towards animals; after all they are our fellow beings. iv. E.g.: If you have pet dogs at home and if they have not seen you for quite some- time, they run towards you the moment you show up and start licking your feet or face. That’s how they show their affection towards you. 3.5 Application to Daily Life, Concern to Bio Diversity Q1. Look at this picture. How do you feel about sibling care nature of animals? Do you ever see such kind of situations in your surroundings? Explain in your own words. [Refer to TB page 104 Q8] SESSION 3. ANIMAL INTELLIGENCE 193

A. i. Sibling care in nature of animals is a representation of animal kindness; some animals go out of their way in caring for other animals. ii. Their generosity is truly amazing. For e.g., you might have seen in newspapers, that dogs adopt kittens even though they are not of their own species. They feed and nurse them. iii. Nurturing the other species may surprise us and even may be inspiring. For these animals, their noble actions are not about recognition but their behaviour. iv. Many animals have been known to take in orphan animals it may be of any species or their own species and raise them. This type of generosity is quite common in animal kingdom. —— CCE Based Practice Questions —— AS1-Conceptual Understanding Very Short Answer Type Questions 1. State true or false. [Refer to Session 7.2 ] (i) Pheromones are chemicals capable of acting outside the body of the secreting indi- vidual to impact the behavior of the receiving individual. [] (ii) Scientists record the signals of animals to study them and out. [ ] (iii) Bats and owls move and search for food during the night only. [ ] (iv) Birds collect material which are weak and brittle to build their nests. [ ] (v) Offspring of different animals which live only on land, perform activities like instinct, imprinting, imitation or conditioning. [] 2. Fill in the blanks. [Refer to Session 7.2 ] (vi) Animals can be tagged by attaching to them. CHAPTER 7. ANIMAL BEHAVIOUR 194

(vii) Animal behaviour is based on different . (viii) is the living home for beavers. (ix) Cockroaches have eyes that are adapted to sense the difference between . 3. Why do you appreciate these animals? Column B [(Session 7.3)] a. For logical thinking Column A i. Squirrel ii. Dolphins b. For constructing dams on water canals iii. Alex (Pet parrot of Evirin Pepperberg) c. For hiding its food from others iv. Tasmanian Devil d. Creativity in language and recognising v. Beaver even minute similarities between two objects e. For spraying bad smell when threat- ened 4. Answer the following questions in one sentence. [Refer to Session 7.3 ] (x) Name a scientists who won the Nobel prize for their work on animal behaviour in 1973. (xi) How do hedehogs protect themselves from predators? CHAPTER 7. ANIMAL BEHAVIOUR 195

(xii) Why did Alex called apple ‘bannery’? (xiii) How can we make dolphins remember their names and learn code language? 5. Fill in the blanks. [Refer to Session 7.3 ] (xiv) is the worst smelling animal in animal kingdom. (xv) Bluffing, hiding and cheating are characteristic of in animal world. (xvi) In order to squirrels dig holes in many places and heap leaves, sticks etc. to cover them. (xvii) After returning from fields in the evening, cow licks its calf which reflects towards its baby. (xviii) is the scientific and objective study of animal behaviour and a sub–topic of zoology. 6. Answer the following questions in one sentence. [Refer to Session 7.1 ] (xix) Why is it important to understand animal behaviour? CHAPTER 7. ANIMAL BEHAVIOUR 196

Short Answer Type Questions 7. Answer the following questions in 3-4 sentences. (i) [(Session 7.2)] What is tagging? (ii) [(Session 7.2)] Mosquitoes and cockroaches come out of their hiding places only when it is dark. How do they know the difference between light and dark? CHAPTER 7. ANIMAL BEHAVIOUR 197

(iii) [(Session 7.2)] What is the arrangement that wasps make for their larvae before laying eggs? (iv) [(Session 7.2)] How do beavers build dams across water streams? 8. Answer the following questions in 3-4 sentences. (i) [(Session 7.3)] What is the special feature of dolphins? CHAPTER 7. ANIMAL BEHAVIOUR 198