202110201-APEX-STUDENT-WORKBOOK-BIOLOGY-G08-PART1

SESSION 2 MICROORGANISMS AS FOES 2.1 Mind Map 2.2 Terminology i. Pathogens – are tiny living organisms, such as a bacterium or virus, that make people sick. ii. Communicable diseases – are those which spread from one person to another or from an animal to a person via airborne viruses or bacteria, through blood or other bodily fluid. iii. Anthrax – is an acute disease caused by the bacterium Bacillus anthracis which causes skin, lung, and bowel disease in animals, especially ruminants. iv. Encephalitis – is an inflammation of the brain majorly caused by viral infection. It can cause flu–like symptoms, such as fever or severe headache. SESSION 2. MICROORGANISMS AS FOES 49

v. Tuberculosis – is an infectious bacterial disease caused by Mycobacterium tuberculosis, which most commonly affects the lungs. 2.3 Key Concepts i. Microorganisms which cause diseases are called as pathogens. Pathogens enter into our body through air we breathe, water we drink and food we eat. ii. Diseases which spread from infected people to healthy ones are known as commu- nicable diseases. Common cold, conjunctivitis, typhoid, smallpox, chickenpox, swine flu, tuberculosis are some of the communicable diseases. iii. Some insects and animals carry disease–causing microorganisms. They are called as vectors. Anopheles mosquito carries plasmodium and thus it is vector. iv. House[U+FB02]ies also carry disease–causing microorganisms and spread the dis- eases like typhoid, cholera etc. v. Some microbes release toxins in improperly preserved food, which causes food poi- soning. 2.4 Information Skills and Projects Q1. Visit the veterinary hospital and prepare a list of cattle diseases by asking questions to the doctor. [Refer to TB page 49 Q7] A. Hint: Students can collect information on the following cattle diseases. Bovine ephemeral fever, Bovine tuberculosis,Brucellosis and Bovine virus diarroea. 2.5 Appreciation and Aesthetic Sense, Values Q1. Raheem tells to his neighbours “Stagnation of sewage in our surroundings is harmful to our health”. Do you support this? Why? [Refer to TB page 49 Q12] A. We support Raheem’s statement as stagnation of sewage in our surroundings may harm us in different ways: SESSION 2. MICROORGANISMS AS FOES 50

i. Stagnation of sewage may cause several diseases as sewage is the breeding ground for various disease–causing pathogens. ii. Vectors such as houseflies sit on garbage, sewage and excreta of infected persons and the disease–causing pathogens stick to their feet. When they come in contact with healthy individuals, these pathogens are transferred to them getting them ill. iii. If these flies come in contact with our food, they transfer the disease–causing germs into the food and renders it unfit for consumption. iv. Consumption of this infected food may lead to food poisoning and several other diseases. 2.6 Application to Daily Life, Concern to Bio Diversity Q1. What are the precautions taken to eradicate malaria? [Refer to TB page 49 Q15] A. The microorganism Plasmodium causes malaria. The female Anopheles mosquito which carries Plasmodium, serves as a vector. By controlling mosquitoes we can pre- vent malaria for which following precautions should be taken: i. Mosquitoes breed in stagnant water. So waste pots, waste flower pots, tires, bowls etc. which may contain stagnant water must be cleared. ii. Preventing mosquito bite is another precaution to prevent oneself from malaria. iii. People must use mosquito nets while sleeping. Use of mosquito coils, mats, liquids etc. at homes is also an effective method to kill mosquitoes. iv. The exposed body parts must be protected with mosquito repellent creams or lotions (like odomos) for preventing mosquito bite. SESSION 2. MICROORGANISMS AS FOES 51

SESSION 3 FOOD PRESERVATION AND OTHER USES 3.1 Mind Map 3.2 Terminology i. Pasteurization – is the process of heating food, especially a beverage such as milk or beer, to a specific temperature for a specific period of time in order to kill microorgan- isms that could cause disease, spoilage, or undesired fermentation. ii. Storage – refers to proper storing of food to maintain food quality by retaining flavor, color, texture and nutrients, while reducing the chance of contracting a food–borne illness. iii. Symbiosis – is the interaction between two different organisms living in close physical association, typically to the advantage of both. iv. Leguminous plants – are plants relating to the pea family (Leguminosae) which pro- duce seeds in pods, distinctive flowers, and typically possess root nodules containing symbiotic bacteria able to fix nitrogen. v. Nitrogen fixation – is a process in which atmospheric nitrogen is converted into am- monium or nitrogen dioxide, forms that are more readily available to the plants. 3.3 Key Concepts i. Water or moisture present in food items helps the microorganisms to grow. ii. Since microorganisms require warmth, food and moisture to grow, removing any one of these would prevent or stop the growth of microorganisms. This principle is used for preservation of food stuffs. iii. Pasteurisation is a method of preservation which involve heating up the milk up to 70 degrees for 15 to 30 sec and then suddenly chilled and stored. SESSION 3. FOOD PRESERVATION AND OTHER USES 52

iv. Lazaro Spallanzani is the first person to prove experimentally that microorganisms could be killed by boiling (1768). v. Dry fruits and vegetables are stored in sealed and air tight packets, which prevents the entry of microbes from outside, thus preserving the food materials for a longer time. vi. Symbiosis is a relationship between rhizobium and many of leguminous plants where rhizobium fixes atmospheric nitrogen and plant give shelter to rhizobium. 3.4 Information Skills and Projects Q1. Visit a nearby milk chilling centre. Observe the process and make a report on them. [Refer to TB page 49 Q10] A. In milk chilling centre, the processing for milk preservation is done in the following events: i. The milk collected from various places comes to the milk chilling center in alu- minium tins. They must reach within 4 or 5 hours from the collection centers. ii. All the milk cans are emptied into a boiling vessel. iii. They are boiled at a temperature of 70°C for 15 to 30 seconds. Due to this heating process all types of microorganisms are destroyed. The milk is germ free. iv. After boiling the milk for a specified time, they are suddenly changed into another vessel where milk is chilled and stored. v. From this small chilling centre, they are transported to a main chilling centre, where they are packed in 1/2 liter or 1 liter packets. These packets are then distributed in various places to people. 3.5 Appreciation and Aesthetic Sense, Values Q1. What is pasteurisation? What is the use of it? [Refer to TB page 49 Q8] A. i. Pasteurisation is a method of preserving milk. ii. Louis Pasteur discovered the process of pasteurisation. iii. During pasteurisation, milk is first heated to about 70 degrees celsius for 15 to 30 seconds and then suddenly chilled. iv. Sudden chilling of milk is done to prevent the growth of microbes. SESSION 3. FOOD PRESERVATION AND OTHER USES 53

—CCE Based Practice Questions — AS1-Conceptual Understanding Very Short Answer Type Questions 1. Answer the following questions in one sentence. [(Session 3.2)] Observe the following figures carefully and choose the appropriate answers given below. (Vaccination, Penicillium sps, Small pox, Inventor of Aureomycin (Dr. Y S Rao), Antibiotics) Column A Column B i. a. Small pox ii. b. Inventor of Aureomycin (Dr. Y S Rao) iii. c. Vaccination iv. d. Penicillium sps. v. e. Antibiotics CHAPTER 3. STORY OF MICROORGANISMS (1 & 2) 54

2. Match the following. Column B [(Session 3.2)] a. Dr. Albert Sabin Column A i. Discovery of penicillium ii. Discovery of aureomycin b. Dr. Alexander Fleming iii. Discovery of oral polio vaccine c. Dr. Edward Jenner iv. Discovery of rabies vaccine d. Dr. Yellapragadda Subba Rao v. Discovery of first vaccine against small e. Louis Pasteur pox 3. Match the various uses of microorganisms with their respective columns. [(Session 3.2)] Column A Column B i. Home a. Preparation of alcohol ii. Commercial use b. Nitrogen fixation in legumes iii. Medicinal use c. Bt cotton iv. Useful for plant d. Preparation of antibiotics and vaccines v. Bacillus thuringiensis e. Preparation of curd, dough 4. Answer the following questions in one sentence. [Refer to Session 3.2 ] (i) What is fermentation? 5. Fill in the blanks. [Refer to Session 3.2 ] (ii) Some microorganisms are used in the preparation of required for curing diseases. CHAPTER 3. STORY OF MICROORGANISMS (1 & 2) 55

(iii) Some microorganisms are farmer’s friend as they increase ____________________. (iv) Soil microbes degrade organic wastes into useful . (v) The process of conversion of sugars into alcohols in the presence of yeast isknown as . (vi) bacterium is present in the root nodules of leguminous plants. 6. Answer the following questions in one sentence. [Refer to Session 3.1 ] (vii) Write any two organisms that we can observe in soil. (viii) Give three examples of viruses. 7. Fill in the blanks. [Refer to Session 3.1 ] (ix) Leeuwenhoek observed small moving organisms under his microscope and named them as . (x) powerful microscope built by Leewenhoek could magnify an object 300 times. (xi) are present everywhere in our surrounding. (xii) help in increasing soil fertility by decomposing the biomass. (xiii) Milk is converted into curd by the bacteria named . (xiv) are found in soil, water and in the alimentary canal of many animals. (xv) Isolation of was possible only after the discovery of electron microscope in 1931. CHAPTER 3. STORY OF MICROORGANISMS (1 & 2) 56

8. Match the given food items with the things used to preserve it. [(Session 3.4)] Column B a. By adding preservatives Column A i. Pickle ii. Fishes b. By drying in sunlight. iii. Jams and jellies c. By adding salt, chilli powder, oil. iv. Vegetable slices d. By adding sugar to them. v. Cold drinks e. By adding salt or by drying in sunlight. 9. Fill in the blanks. [Refer to Session 3.4 ] (xvi) The present in the food helps the microorganisms to grow. (xvii) emits bad smell and also tastes bad. (xviii) Vegetable slices and fish are preserved by and . (xix) was the first to prove experimentally that microorganisms could be killed by boiling. (xx) helps in killing several types of microorganisms present in milk. (xxi) helps to inhibit the growth of microorganisms. (xxii) Pasteurisation was discovered by . (xxiii) Invention of pasteurisation led to the invention of the process. (xxiv) The bacterium present in root nodules of many leguminous plants responsible for is . CHAPTER 3. STORY OF MICROORGANISMS (1 & 2) 57

Short Answer Type Questions 10. Answer the following questions in 3-4 sentences. (i) [(Session 3.3)] What is a communicable disease? Give examples. 11. Answer the following questions in 3-4 sentences. (i) [(Session 3.1)] Describe the special features of viruses. Long Answer Type Questions 12. Answer the following questions in 3-4 sentences. (i) [(Session 3.3)] What is food poisoning? Which organisms are responsible for food poisoning? AS2-Asking questions and making hypothesis Short Answer Type Questions 13. Answer the following questions in 3-4 sentences. (i) [(Session 3.2)] Sheila’s little brother was vaccinated and he got fever after that. Sheila wondered and got many doubts. What doubts she could have posed to her mother regarding vaccination? AS3-Experimentation and field investigation Short Answer Type Questions 14. Answer the following questions in 3-4 sentences. (i) [(Session 3.1)] Sujata wants to have a look at protozoa. Which method should she follow for growing and observing the protozoans? CHAPTER 3. STORY OF MICROORGANISMS (1 & 2) 58

Long Answer Type Questions 15. Answer the following questions in 6-8 sentences. (i) [(Session 3.1)] Describe experimentally what happens when sugar is added to yeast? Also mention its industrial uses. AS4-Information skills and projects Long Answer Type Questions 16. Answer the following questions in 6-8 sentences. (i) [(Session 3.4)] Read the following paragraph and answer the questions given below. Fishes are preserved by adding salt or smoking them. Jams and jellies are preserved by adding sugar after boiling fruits or fruit extracts. Vegetable slices and fishes are preserved by adding salt and drying in the sunlight. In all these processes water or moisture is removed from the food items. Thus microbes cannot grow in these conditions. i. How are fishes preserved? ii. Why do we add sugar to jams or jellies? iii. How do we preserve vegetable slices? iv. What is common in all the above processes? v. Why cannot the microbes grow in the food items after preserving them using mentioned methods? AS5-Communication through drawing and model making Very Short Answer Type Questions 17. Answer the following questions in one sentence. [Refer to Session 3.4 ] (i) Identify the disease represented in the given picture. CHAPTER 3. STORY OF MICROORGANISMS (1 & 2) 59

Long Answer Type Questions 18. Answer the following questions in 6-8 sentences. (i) [(Session 3.2)] Draw a table showing atleast five useful and five harmful microorgan- isms. Format given below. The table should contain information about their nature, where they are found, and how are they useful or harmful. Name of the Useful/harmful Nature Place cUasuesseosr microorgan- they are ism found AS6-Appreciation and aesthetic sense, Values Very Short Answer Type Questions 19. Answer the following questions in one sentence. [Refer to Session 3.2 ] (i) Which scientist is appreciated for discovering tetracycline? Short Answer Type Questions 20. Answer the following questions in 3-4 sentences. (i) [(Session 3.2)] Your teacher says “Unnecessary use of antibiotics is harmful to human body.” How would you appreciate this statement? CHAPTER 3. STORY OF MICROORGANISMS (1 & 2) 60

Objective Questions AS1-Conceptual Understanding 21. Choose the correct answer. (i) Pathogens can enter into our body through: (A) Air (B) Water (C) Food (D)All the above (ii) Which of the following information is wrong? (A) Diseases such as typhoid, tuberculosis and septicemia (blood poisoning) are caused by bacteria. (B) AIDS, polio, swine flu, conjunctivitis, and chickenpox are caused by viruses. (C)Microarthropods helps in increasing soil fertility. (D)Tobacco mosaic virus causes cancer to the people who chew tobacco products like zarda, gutka, and tambakoo etc. (iii) The diseases which spread from infected persons to healthy ones are known as: (A) Motile disease (B) Fertile disease (C)Communicable disease (D)Mobile disease (iv) Dr. Ronald Ross got nobel prize for discovering malarial parasite in: (A) Male anopheles (B) Female anopheles (C) Aedes (D)Female culex (v) Animals that carry microorganisms are called: (A) Vectors (B) Vehicles (C) Vendors (D) Carrier CHAPTER 3. STORY OF MICROORGANISMS (1 & 2) 61

(vi) Pond water is greenish because of the growth of: (A) Algae (B) Fungi (C)Tobacco mozaic virus (D)Green rugs (vii) This bacterium is widely responsible for causing food poisoning. (A) Clostridium vivax (B) Vibrio cholera (C)Clostridium botulinum (D) Mycobacterium (viii) This disease is not caused by viruses. (B) Polio (A) Swine Flu (C) AIDS (D) Scabies (ix) Thiomargarita namibiensis is the largest micro organism belonging to this group. (A) Fungi (B) Protozoa (C) Bacteria (D) Algae AS4- Information skills and projects 22. Choose the correct answer. (x) Based on the information about groups of microorganisms, sort the odd one out of the given options. (A) Amoeba (B) Paramoecium (C) Rhizopus (D) Vorticella CHAPTER 3. STORY OF MICROORGANISMS (1 & 2) 62

AS5 - Communication through drawing and model making 23. Choose the correct answer. (xi) Observe the picture (A) The given image is of animal scabies mite. (B) It causes scabies disease. (C)It is a microarthoropod. (D)All the above CHAPTER 3. STORY OF MICROORGANISMS (1 & 2) 63

4. REPRODUCTION IN ANIMALS SESSION 1 INTRODUCTION AND ASEXUAL REPRODUCTION 1.1 Mind Map SESSION 1. INTRODUCTION AND ASEXUAL REPRODUCTION 64

1.2 Terminology i. Reproduction – is the biological process by which new individual organisms (offsprings) are produced from their parents. ii. Asexual reproduction – is the type of reproduction where fusion of gametes does not take place. Budding, fission etc are common methods. iii. Budding – is the type of asexual reproduction in which a new individual or branch develops from an outgrowth on the body of a plant or certain lower animals. iv. Binary fission - is a type of asexual reproduction in which an animal reproduces by dividing into two individuals. 1.3 Key Concepts i. Oviparous animals are the animals that reproduce by laying eggs. Oviparous animals are hen, frog, lizard, butterfly etc. ii. Viviparous animals are animals that reproduce by giving birth to live young. Viviparous animals are human beings, cows, dogs etc. iii. Reproduction is one of the basic life processes which is essential for the continuation of the species. iv. The type of reproduction where a single parent is involved and fusion of gametes does not take place is called asexual reproduction. v. Budding as seen in hydra is a type of asexual reproduction where new individuals develop from the buds. vi. The type of asexual reproduction in which an animal reproduces by dividing into two individuals is called Binary Fission. Amoeba reproduce asexually through binary fis- sion. SESSION 1. INTRODUCTION AND ASEXUAL REPRODUCTION 65

1.4 Conceptual Understanding Q1. Compare the reproduction in hydra and amoeba. Note down the differences in your notebook. [Refer to TB page 67 Q2] A. Hydra Amoeba i. In hydra, both sexual and i. In amoeba only asexual asexual reproduction take reproduction takes place. place. ii. During asexual ii. No bulges are formed on reproduction, 2 or 3 bulges the body during division. develop on the body of When nucleus matures it hydra. starts dividing. iii. The bulges gradually iii. The nucleus divides into increase into small buds daughter nuclei and which detach from the constriction appears on the parent and attach to any body which deepens to give other substratum and lead a rise to two daughter free life. amoeba. iv. After budding, the parent iv. After binary fission, the hydra remains as before. parent body disappears forever as it has divided into two daughter cells. SESSION 1. INTRODUCTION AND ASEXUAL REPRODUCTION 66

Q2. Can animals produce offsprings even without formation of zygote, how? Explain with suitable examples. [Refer to TB page 68 Q4] A. i. In some animals, formation of gametes does not take place. Still they produce offsprings like themselves. ii. In the absence of gamete formation, there is no fusion of gametes. Such process of reproduction is called asexual reproduction. iii. Eg: Hydra and Amoeba. Q3. How can you identify the animal is viviparous or oviparous? [Refer to TB page 68 Q5] A. Viviparous animals giving birth to young ones have external ears and epidermal hair on their skin. On the other hand, oviparous animals that lay eggs do not have epidermal hair or external ears. Q4. Differentiate between: [Refer to TB page 67 Q1] (a) sexual reproduction and asexual reproduction (b) gametes and zygote (c) external fertilization and internal fertilization (d) viviparous and oviparous animals A. (a) Sexual Reproduction Asexual Reproduction i. Both parents are involved. i. Single parent is involved. ii. Male and female gametes ii. There is no fusion of fuse to form a zygote. Eg., gametes. Eg., Budding in Reproduction in frog, Hydra, Binary fission in humans etc. Amoeba etc. SESSION 1. INTRODUCTION AND ASEXUAL REPRODUCTION 67

(b) Zygote Gametes In sexual The fusion of the male and the reproduction, the male female gametes, the sperm and and female parents the ovum respectively, is called produce gametes, fertilization. The product of which carry incomplete fertilization, i.e., the fertilised egg information about the is called zygote. offspring. (c) External Fertilization Internal Fertilization When fertilization of When fertilization of gametes takes place outside gametes takes place inside the female body, it is called the female body, it is called external fertilization. internal fertilization. Eg. In fishes and frogs. Eg. In humans. (d) Viviparous animals Oviparous animals Animals such as human Animals such as hen, beings, cows and dogs which frog, lizard and butterfly give birth to young ones are which lay eggs are called called viviparous animals. oviparous animals. 1.5 Asking Questions and Making Hypothesis Q1. What would happen if all the organisms would stop the process of reproduction? [Refer to TB page 69 Q11] A. All organisms multiply their number by the process of reproduction. If there will be no reproduction, then there will be no propagation of organisms and at some time in future, all the organisms will become extinct from this world. SESSION 1. INTRODUCTION AND ASEXUAL REPRODUCTION 68

SESSION 2 SEXUAL REPRODUCTION 2.1 Mind Map 2.2 Terminology i. Gamete – is a mature haploid male or female germ cell which is able to unite with another of the opposite sex in sexual reproduction to form a zygote. ii. Uterus – is a hollow, pear–shaped organ located in a woman’s lower abdomen where development of the baby takes place. iii. Pregnancy – is the state of carrying a developing embryo or foetus within the female body. iv. Offspring – are the individual organism(s) resulting from sexual or asexual reproduc- tion. v. Bisexual animals – also called as hermaphrodites, these animals carry both male and female reproductive organs in their body. vi. Epidermal hair – are the hair that grow from epidermis, i.e., skin in animals. SESSION 2. SEXUAL REPRODUCTION 69

2.3 Key Concepts i. In Sexual reproduction the fusion of the male reproductive cell and female reproduc- tive cell takes place, i.e., the ovum of the female and the sperm of the male fuses to form the zygote. ii. The male reproductive organs includes a pair of testis, two sperm ducts and penis. iii. The testes are egg shaped, produce the male gametes or sperms. iv. The female reproductive organs contains a pair of ovaries, oviducts and uterus. v. The ovary produces female gametes called ova. vi. The type of fertilization which takes place inside the female body is called internal fertilization. It occurs in different organism like insects, snake, lizards etc. vii. The zygote divides repeatedly to develop into an embryo, which develops further in the uterus. viii. The period from formation of zygote to fully developed foetus is called pregnancy period. ix. IVF –In Vitro Fertilization 2.4 Conceptual Understanding Q1. Who am l? [Refer to TB page 68 Q6] i. I am formed by the fusion of male and female gametes. ii. I am a gamete that has a tail and travel to fuse with female gamete. iii. I am a fully developed embryo inside a mother’s body. A. i. Zygote is formed by the fusion of male and female gametes. ii. Sperm is the male gamete that has a tail and travel to fuse with female gamete. iii. Foetus is the fully developed embryo inside mother’s body. SESSION 2. SEXUAL REPRODUCTION 70

Q2. State the reason why in most of the terrestrial animals, fertilization takes place internally. [Refer to TB page 68 Q7] A. i. Internal fertilization is required for terrestrial animals because the chance that sperm and egg would come into contact with each other by any other way is very slim. ii. Internal fertilization allows the sperm to be deposited in a close proximity to the egg, thus increasing the chance of its fertilization. iii. If terrestrial animals released their eggs and sperms in the external environment, sperm can never reach the egg in the absence of water as medium to float. iv. Also the eggs and sperms may wither or get destroyed by sunlight and other ex- ternal factors. Q3. Observe the following pictures and write the functions of them. [Refer to TB page 68 Q8] A. i. This is the figure of a testes present in the male reproductive system. It produces male gametes called sperms. ii. This is the picture of an ovary and oviduct or fallopian tube. Ovary produces ovum, the female gamete and this ovum is released into the fallopian tube. iii. This is the picture of a human sperm cell. It is the male gamete which fuses with the ovum to form the zygote. iv. This is the figure of fertilization. One of the sperm penetrates through the outer covering of the ovum and fuses with it to form the zygote. SESSION 2. SEXUAL REPRODUCTION 71

2.5 Communication Through Drawing and Model Making Q1. Sketch the diagrams of male and female reproductory systems. [Refer to TB page 69 Q14] A. SESSION 2. SEXUAL REPRODUCTION 72

SESSION 3 FERTILISATION OUTSIDE THE BODY 3.1 Mind Map SESSION 3. FERTILISATION OUTSIDE THE BODY 73

3.2 Terminology i. External fertilization – refers to the union of male and female gametes taking place outside the bodies from which they originated, such as in frogs and most fishes. ii. Tadpole– is the larval stage in the life cycle of a frog which resembles a fish and possesses fins and gills for respiration. iii. Copulation – is the breeding of male and female of any species. iv. Metamorphosis – is the transformation of the larva into adult through drastic changes. v. Cloning – is the process of producing similar populations of genetically identical in- dividuals that occurs in nature when organisms such as bacteria, insects or plants reproduce asexually. 3.3 Key Concepts i. The process of fertilization that occurs outside an organism’s body is called external fertilization. This type of fertilization is common in fish, starfish etc. ii. The transformation of the larva into adult through drastic changes is called metamor- phosis. iii. If an animals possesses both male and female reproductive organs, it is a bisexual or hermaphrodite animal. iv. The first cloned animal is a sheep named Dolly. It was performed by Ian Wilmut in 1996. 3.4 Conceptual Understanding Q1. Why do fish and frog lay more number of eggs whereas cow and human beings usually give birth to only one at a time? [Refer to TB page 68 Q3] A. i. Though animals like frog and fish lay hundreds of eggs and release millions of sperms, all the eggs do not get fertilised and develop into new individuals. This is because the eggs and sperms get exposed to water movement, wind and rainfall. ii. Also, there are other animals in the pond which may feed on eggs. Thus, produc- tion of a large number of eggs and sperms is necessary to ensure fertilisation of at least a few of them. SESSION 3. FERTILISATION OUTSIDE THE BODY 74

iii. On the other hand, in cows and human beings, internal fertilisation takes place, where the sperm is released in very close proximity to the egg. Hence the chances of fertilisation are very high. Hence, they only need to produce one offspring at a time. Q2. (a) By taking help of the given words, label the following life cycle: eggs, adult, pupa, larva. [Refer to TB page 68 Q9] (b) Explain the process of metamorphosis in housefly by taking help from the above diagram. A. (a) (b) The transformation of the larva into an adult through drastic changes is called meta- morphosis. In the above figure of metamorphosis of housefly, the adult first lays eggs. The eggs hatch into larvae. The larvae grow slowly to form the pupa. The pupa finally changes into the adult housefly that we commonly see. SESSION 3. FERTILISATION OUTSIDE THE BODY 75

Q3. Match The Following: [Refer to TB page 68 Q10] A. 3.5 Experimentation and Field Investigation Q1. Kavitha found a tadpole in a pond. She collected it carefully and put it in an aquarium, supposing it to be a fish. After some days, what did she find and why? [Refer to TB page 69 Q12] A. i. Kavitha thought that tadpole is a fish because the tadpole resembles a fish. It possesses gills for breathing and a tail bearing fins on it. ii. After a few days, the tadpole undergoes metamorphosis to become a small frog without gills and tail, but having two pairs of limbs. iii. After metamorphosis, transformation of shape of the body occurs and over a period of time they resemble their parents. SESSION 3. FERTILISATION OUTSIDE THE BODY 76

3.6 Information Skills and Projects Q1. Collect information from your library or from other sources like the internet and dis- cuss the life cycle of honey bee in the symposium at your school. [Refer to TB page 69 Q13] A. Life cycle of Honey Bee i. The queen bee lays the eggs, after a few weeks the egg turns into larva. ii. When the larva is about five days old the worker bees cover the opening with wax. iii. Larva develops inside a cocoon into a pupa that metamorphoses into adult bee after two to three weeks. SESSION 3. FERTILISATION OUTSIDE THE BODY 77

3.7 CCoommmmuunniiccaattiioonn TThhrroouugghh DDrraawwiinngg aanndd MMooddeell MMaakkiinngg Q1. Draw labelled diagram of life history of frog and identify forms which are herbivores. [Refer to TB page 69 Q15] A. Life history of Frog: SESSION 3. FERTILISATION OUTSIDE THE BODY 78

Most tadpoles are herbivorous and during metamorphosis the mouth and internal or- gans are rearranged to prepare for an adult carnivorous lifestyle. 3.8 Application to Daily Life, Concern to Bio Diversity Q1. How would you appreciate Ritwik’s work when he kept back the pigeon squab in the ventilator? If you were in Ritwik’s place what would you do? [Refer to TB page 69 Q16] A. We appreciate Ritwik for keeping the pigeon squab in the ventilator. By doing this, he had saved the lives of two new pigeons which had hatched from the eggs. If I were in his place, I would also have liked to save lives and would have done the same as Ritwik. SESSION 3. FERTILISATION OUTSIDE THE BODY 79

—— CCE Based Practice Questions —— AS1-Conceptual Understanding Very Short Answer Type Questions 1. State true or false. [Refer to Session 4.1 ] (i) Whale is also an oviparous animal like all fishes. [ ] ] (ii) Division of nucleus also takes place during binary fission. ] [ (iii) Multiple fission and fragmentation are also types of asexual reproduction. [ 2. Answer the following questions in one sentence. [Refer to Session 4.1 ] (iv) What is reproduction? (v) What are two modes of reproduction? 3. Fill in the blanks. [Refer to Session 4.1 ] (vi) have external ears and epidermal hairs on their skin. (vii) The type of reproduction where fusion of gametes does not take place is called . CHAPTER 4. REPRODUCTION IN ANIMALS 80

(viii) reproduction is common in microorganisms. is (ix) is observed in hydra and observed in amoeba. 4. Match the following. Column B [(Session 4.3)] Column A a. Cloning b. Whale i. Internal fertilization c. Frog ii. External fertilization d. Fish iii. Dolly e. In vitro fertilization iv. Test tube baby v. Metamorphosis 5. Answer the following questions in one sentence. [Refer to Session 4.3 ] (x) Define Metamorphosis. 6. Fill in the blanks. [Refer to Session 4.3 ] (xi) External fertilization is very common in . (xii) If the animal possesses only one type of reproductive organs (male or female),it is called a . CHAPTER 4. REPRODUCTION IN ANIMALS 81

(xiii) The first cloned animal is the sheep Dolly and the technique was performed by in the year . (xiv) If an animal possesses both male and female reproductive organs within its body, it is known as . Short Answer Type Questions 7. Answer the following questions in 3-4 sentences. (i) [(Session 4.2)] Describe the male reproductive system. (ii) [(Session 4.2)] What are the steps involved in IVF? Long Answer Type Questions 8. Answer the following questions in 6-8 sentences. (i) [(Session 4.2)] Write a note on fertilization and its types. AS2-Asking questions and making hypothesis Short Answer Type Questions 9. Answer the following questions in 3-4 sentences. (i) [(Session 4.2)] Why is sexual reproduction not possible in amoeba/ hydra? Provide your hypothesis. CHAPTER 4. REPRODUCTION IN ANIMALS 82

AS3-Experimentation and field investigation Short Answer Type Questions 10. Answer the following questions in 3-4 sentences. (i) [(Session 4.3)] While investigating your school garden, you see a small tiny colorful larvae feeding on leaves. What do you call it? Describe the process of its growth. Long Answer Type Questions 11. Answer the following questions in 6-8 sentences. (i) [(Session 4.3)] How can one produce an exact copy of a cell or organism? Describe the method in details. AS4-Information skills and projects Long Answer Type Questions 12. Answer the following questions in 6-8 sentences. (i) [(Session 4.2)] Prepare a project report on “test tube babies”. AS5-Communication through drawing and model making Very Short Answer Type Questions 13. Answer the following questions in one sentence. [Refer to Session 4.3 ] (i) Provide a schematic representation of the life cycle of Housefly/ butterfly. Long Answer Type Questions 14. Answer the following questions in 6-8 sentences. (i) [(Session 4.3)] Prepare a poster on cloning of dolly sheep. CHAPTER 4. REPRODUCTION IN ANIMALS 83

AS6-Appreciation and aesthetic sense, Values Very Short Answer Type Questions 15. Answer the following questions in one sentence. [Refer to Session 4.3 ] (i) How will you appreciate the role of water in external fertilization? Short Answer Type Questions 16. Answer the following questions in 3-4 sentences. (i) [(Session 4.2)] How will you appreciate the structure of female reproductive organ in human, for development of embryo? Objective Questions AS1-Conceptual Understanding 17. Choose the correct answer. (i) Reproduction resulting from the fusion of male and female gametes is called as (A) sexual reproduction (B) asexual reproduction (C)both A and B (D)none of the above (ii) Reproductive organs of a male consist of (A) testes (B) sperm ducts (C) penis (D)all of above (iii) Metamorphosis does not take place in which of these organisms? (A) Frog (B) Fish (C) Butterfly (D)Silk worm CHAPTER 4. REPRODUCTION IN ANIMALS 84

(iv) Sameera’s oviduct was blocked. She can go for to give birth to her child. (A) in vitro fertilization (B) test tube baby (C) cloning (D) both A and B (v) Frogs croak in rainy season (B) To stop the rain (A) To attract females (D)To cry (C)To sing and enjoy rain (vi) Epidermal hair and external ears are characteristic features of which animals? (A) Hermaphrodites (B) Asexually reproducing organisms (C)Sexually reproducing animals (D)Viviparous animals (vii) Fusion of male and female gamete results in the formation of (A) embryo (B) foetus (C) zygote (D) ovum (viii) Which male reproductive organ produces sperms? (A) Seminal ducts (B) Penis (C)Scrotal sac (D) Testes CHAPTER 4. REPRODUCTION IN ANIMALS 85

(ix) The period from zygote to fully developed foetus is called period. (A) lactation (B) pregnancy (C) gestation (D)none of these AS4-Information skills and projects 18. Choose the correct answer. (x) On the basis of your information about stem cell therapy, provide correct information about the given statement. ”Human stem cell can be produced by” (A) Cloning (B) Cell and tissue culture (C) EMR (D)Both A and B AS5-Communication through drawing and model making 19. Choose the correct answer. (xi) Which of the given flowchart provides correct information about asexual reproduc- tion? (A) (B) (C) (D) CHAPTER 4. REPRODUCTION IN ANIMALS 86

5. ATTAINING THE AGE OF ADOLESCENCE SESSION 1 INTRODUCTION AND CHANGES AT ADOLESCENCE 1.1 Mind Map 1.2 Terminology i. Teenage – is a young person/child whose age falls within the range from 13–19. They are called teenagers because their age number ends with “teen”. ii. Larynx – is the hollow muscular organ forming an air passage to the lungs and holding the vocal cords in humans and other mammals. iii. Adam’s apple – is the projection at the front of the neck formed by the thyroid cartilage of the larynx, often prominent in men. iv. Maturity – When something reaches his full level of development, he is said to have achieved maturity. v. Sweat glands – are small tubular structures of the skin that produces sweat. vi. Sebaceous glands – are microscopic exocrine glands in the skin that secrete an oily or waxy matter, called sebum, to lubricate and waterproof the skin and hair of mammals. vii. Hormones – are chemical messengers that are secreted directly into the blood, which carries them to organs and tissues of the body to exert their functions. viii. Behavioural changes – include several social and emotional changes taking place during adolescence. SESSION 1. INTRODUCTION AND CHANGES AT ADOLESCENCE 87

ix. Physical changes – include development of secondary sexual characters, maturation of sex organs, increase in height, formation of pimples etc. x. Pimples – are small skin lesions or inflammations of the skin. They are sebaceous glands which are infected with bacteria, swell up, and then fill up with pus. 1.3 Key Concepts i. Adolescence is the period of reproductive maturity which is attained between the ages of 10 to 18 years. ii. Growth is one of the important characteristic in human beings. An individual reaches his / her maximum height during adolescence period only. iii. Changes in body takes place for both boys and girls which involves broadening of shoulder for boys and widening of waist for girls. iv. The voice change in childhood and especially during adolescence is due to the devel- opment of Adam’s apple at the larynx or voice box. v. The development of pimples on the face is due to increased activity of sweat and sebaceous glands in the skin. 1.4 Conceptual Understanding Q1. How is adolescence different from childhood? [Refer to TB page 83 Q1] A. Childhood Adolescence i. The age between 5 i. The age between 13 and 19 and 12 years is called years is called adolescence. childhood. ii. Voice is soft and ii. The voice becomes hoarse and mostly resembles that difference between male & female of girls in even boys voice becomes apparent. SESSION 1. INTRODUCTION AND CHANGES AT ADOLESCENCE 88

Childhood Adolescence iii. All the children play iii. Adolescents want to spend together. his/her time with peers only. iv. Increase in height iv. Increase in height and weight is and weight is often more considerable. little. v. No development of v. Development of Secondary secondary sexual sexual characters takes place. characters. Q2. Write short notes on the following: [Refer to TB page 83 Q2] (a) Secondary sexual characters (b) Adam’s apple A. (a) Secondary sexual characters: During adolescence, changes occur in external and internal parts of the body, which were not present at birth. In girls breasts begin to develop, whereas in boys, moustaches and beard begin to grow. Hair starts growing on the chest of boys. In both boys and girls hair grows in armpits and at the genital region. These changes are called secondary sexual characters. (b) Adam’s apple: The Adam’s apple is actually a partial growth of voice box or larynx. The larynx is made up of 9 cartilages. The Adam’s apple is formed due to elongation of the thyroid cartilage. The laryngeal prominence is usually more prominent in adult men than in adolescent boys. Adam’s apple is responsible for change of voice in boys to hoarse during adolescence. Q3. List out the changes in the body that take place at the age of adolescence. [Refer to TB page 83 Q3] A. The period between the ages of 13 –19 years is called adolescence. During adoles- cence, the main changes are as follows: i. Moustache growth on the upper lip of boys and breasts development in girls. ii. Voice changes to hoarse in boys. iii. External hair growth under armpits. iv. Pimples occur in few adolescents. SESSION 1. INTRODUCTION AND CHANGES AT ADOLESCENCE 89

v. Behavioural changes such as more concern and consciousness towards one’s appearance and lack of interest to play with opposite sex. vi. They feel restless of their parents’ questions. vii. Adolescents want to spend their time with peers only. viii. Maximum growth in height in both boys and girls is observed during adolescence. Q4. Why acne and pimples are common in adolescents? [Refer to TB page 83 Q5] A. The secretions of sweat and sebaceous glands cause the development of pimples on the skin of adolescent boys and girls. During adolescence the secretion is more than in any other stage. Hence acne and pimples are common in adolescents. 1.5 Asking Questions and Making Hypothesis Q1. If you have a chance to talk with a doctor, what questions you would ask about adoles- cent emotions and changes in the body? [Refer to TB page 83 Q7] A. On getting a chance to speak to a doctor, here are some questions that I would like to ask: i. Why adolescents are so emotional? ii. Is interest towards body and self, natural? iii. Is attraction towards opposite sex a normal response? iv. Is acne normal during this age, how can I get rid of this? 1.6 Experimentation and Field Investigation Q1. Some mobile phones have auditory meters to measure frequency of produced sound. By using this phone measure your friends’ voice frequency, one from each class VI to X. Report your findings. [Refer to TB page 83 Q8] SESSION 1. INTRODUCTION AND CHANGES AT ADOLESCENCE 90

A. Student’s Frequency of voice (DB) class VI 20DB VII 22DB VIII 23DB IX 25DB X 26DB 1.7 Application to Daily Life, Concern to Bio Diversity Q1. 13 years old Swaroop always thinks of his height. Can he improve his height? What would you suggest him ? [Refer to TB page 83 Q13] A. i. Children during adolescence grow to a maximum height. Boys generally attain their maximum height by the age of 18 years. ii. During adolescence, there is a spur of growth in height especially till 16 years of age. iii. We would suggest Swaroop to eat nutritious and balanced food with plenty of proteins. iv. He should exercise and involve in physical activities like cycling etc. which are known to help in increasing height. SESSION 1. INTRODUCTION AND CHANGES AT ADOLESCENCE 91

SESSION 2 DEVELOPMENT OF SEX ORGANS 2.1 Mind Map 2.2 Terminology i. Primary sexual characters– are the sex organs by which children are identified as boys or girls at birth. ii. Secondary sexual characters – are the features that appear at sexual maturity in ani- mals and during puberty in humans. iii. Menstruation cycle – While ovulation in human females which takes place every month, if the egg is not fertilized, the lining of the uterus sheds through the vagina along with the egg. iv. Child marriage – refers to marriage before the legal age of 21 for boys and 18 for girls. It is a social evil which causes unwanted damage to the lives of children. v. Testosterone – The male hormone that brings about development of several sec- ondary sexual characters in males. vi. Estrogen – The female hormone that brings about development of several secondary sexual characters in females. SESSION 2. DEVELOPMENT OF SEX ORGANS 92

vii. Balanced diet –consists of proteins, carbohydrates, fats and vitamins in requisite pro- portions. It provides healthy nutrition to the body for proper functioning. 2.4 Key Concepts i. The sex organs by which children are identified as boys or girls at birth represent primary sexual characters. ii. In case of girls, the breasts begin to develop and in boys’ facial hair, moustache and beard begin to grow. In both boys and girls, hair grows in the armpits and genital area. These are called ‘secondary sexual characters’. iii. Adolescents become capable of reproduction when their testes and ovaries begin to produce gametes. iv. The first menstrual cycle in female begins at adolescence which is termed as menar- che. v. Menopause is the stage where the menstrual cycle stops at the age 45 to 50 years. vi. In India, the legal age for marriage is 18 years for girls and 21 years for boys. Child marriage is a social evil which causes unwanted damage to the lives of children. vii. Testosterone is a male hormone released by the testes. It is responsible for release of sperm and secondary sexual characters in male. viii. Ovaries produce the female hormone estrogen which is responsible for release of ovum, menstruation, embryo implantation and secondary sexual characters in female ix. Hunger levels of adolescents are usually very high, and it is very important to take balanced diet for overall growth and development during this period. SESSION 2. DEVELOPMENT OF SEX ORGANS 93

2.5 Conceptual Understanding Q1. Match the following: [Refer to TB page 83 Q4] A. Column A Column B 1. Testes c. Sperm 2. Endocrine gland b. Pituitary 3. Menarche d. First menstruation 4. Female hormone a. Estrogen Q2. What can you suggest to your classmates to keep himself/ herself clean and healthy? [Refer to TB page 83 Q6] A. Some suggestions for keeping ourselves clean and healthy are as follows: i. It is a good practice to bath at least twice a day to keep the sweaty odour and germs away. ii. All parts of the body and innerwears should be washed and cleaned every day, otherwise fungal, bacterial or other infections may occur. iii. Girls should take special care of cleanliness during the time of menstruation. At that time they must use disposable napkins. iv. All young boys and girls should exercise and play outdoors to be fit and healthy. Also, taking a balanced and healthy diet is a key to healthy life. SESSION 2. DEVELOPMENT OF SEX ORGANS 94

2.6 Appreciation and Aesthetic Sense, Values Q1. Write five suggestions to improve the performance of Red Ribbon club of your school. [Refer to TB page 83 Q9] A. A Red Ribbon club aims at harnessing the potential of the youth and students towards values of service, development of healthy lifestyle and encouraging blood donation to needy. Some suggestions to improve the performance of Red Ribbon club are: i. To instil life skills into youth to lead a better and healthier life. ii. To ensure that every youth in the state is equipped with conceptual knowledge about various basic health aspects which he may possibly encounter during his life. iii. To motivate youth and build their attitude as peer educators, by developing their skills on leadership, negotiation, and team building. iv. Promote regular voluntary blood donation under expert supervision by young peo- ple and increase access to safe and adequate quantities of blood. v. To develop essential skills to cope with adverse conditions pertaining to health. Q2. Nature prepares human body to reproduce her generations. What do you think of it? [Refer to TB page 83 Q11] A. Reproduction is essential for continuation of human race. During adolescence, nature prepares the human body to be able to reproduce. i. The reproductive organs in males and females mature and start producing testos- terone in males and estrogen in females during adolescence. ii. These hormones bring about changes in secondary sexual characters as well as lead to the production of sperms in males and ovum in females. iii. This production of gametes in males and females begins between 11–15 years of age. iv. In females, the ovary begins to mature one ovum once in about every 28 to 30 days. v. During this period, the wall of the uterus becomes thick to receive a fertilized egg and, if fertilisation occurs by fusion with the sperm, it results in pregnancy. SESSION 2. DEVELOPMENT OF SEX ORGANS 95

vi. Released ovum when unfertilized is released out of the body during menstrua- tion alongwith blood. The first menstrual cycle begins during adolescence and is termed as menarche. vii. Female is also prepared for motherhood by the development of breasts and mam- mary glands. viii. These changes prepares the human body for reproduction and continuation of life. Q3. You know that early marriage is a social taboo. Prepare some slogans to prevent this. [Refer to TB page 83 Q12] A. The legal age for marriage is 18 years for girls and 21 years for boys. Some slogans to prevent child marriage earlier than this legal age are as under: i. Say no to early marriage ii. Young mothers unprepared for motherhood iii. Early marriage –A social sin iv. Educate young girls and boys, do not get them married v. Earn first, get married only next Q4. Prepare a three minute speech on behavioural changes in adolescence. [Refer to TB page 83 Q10] A. Adolescence is the growing age in which along with physical changes, several be- havioural changes also take place. i. They are very fast in taking decisions which they sometimes regret later. ii. They don’t like being told or dictated to do any work against their will. iii. They exhibit mood swings, sometimes they would behave peculiarly for some rea- son and act rigid. iv. Interest towards body care and appearance increases and an attention towards opposite sex develops. v. They are zealous and develop abstract ideas also. vi. They are more independent and very self–conscious. vii. They feel insecure so they seek company of friends to share their feelings even about opposite sex. viii. They need a lot of attention, love and care as well as an answer to all their queries regarding their body and its development. SESSION 2. DEVELOPMENT OF SEX ORGANS 96

2.7 Application to Daily Life, Concern to Bio Diversity Q1. Are you angry with your parents? How do you wish your parents to be? [Refer to TB page 83 Q14] A. Answer this question using the clues given below: I am . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . (angry / not angry ) with my parents I am angry because: i. They ask me to study all the time. I am not angry because: i. They give me the freedom to plan my time. ii. They don’t force me to study all the time, they are happy with the marks I get. I want my parents to be friendly and encouraging. They should be like my friends. They should discuss with me about my opinion and about things I like. They should talk about studies and also about movies with me. They must not compare me with others. Q2. What are your expectations regarding your parents and teachers? [Refer to TB page 83 Q15] A. Some of the expectations that we have from our parents and teachers are listed be- low. Parents and teachers should: i. Be friendly and encouraging. ii. Clarify all our doubts without scolding. iii. Not beat/scold us, specially in front of others. iv. Not compare us with anyone. v. Give us time to play outside. SESSION 2. DEVELOPMENT OF SEX ORGANS 97

—— CCE Based Practice Questions —— AS1-Conceptual Understanding Very Short Answer Type Questions 1. Answer the following questions in one sentence. [Refer to Session 5.1 ] (i) Write the formula to find the percentage of full height for a given age. 2. Fill in the blanks. [Refer to Session 5.1 ] (ii) of the body grow more prominently in boys than in the girls. prominence is usually more in adult men than in adolescent (iii) boys. (iv) Larynx is made up of cartilages. (v) An individual reaches his or her maximum height during period. 3. State true or false. [ ] [Refer to Session 5.2 ] [ ] (vi) Women during the period of menstruation are untouchable. (vii) Hunger levels of adolescents are very high. CHAPTER 5. ATTAINING THE AGE OF ADOLESCENCE 98