BIOLOGY

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17th edition

I SB N SYLLABUS COVERED

year 2021-22 “978-93-5423-426-2”

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TABLE OF CONTENTS  Latest CBSE Circular & Syllabus released on 22 July 2021 for Academic Year 2021-2022 (CBSE Cir. No. Acad 53/2021)  Supplement : Latest Typologies of Questions introduced by CBSE for 2022 Exam  Solved Paper 2020 (Delhi/Outside Delhi Sets)  Topper’s Answer 2019 (Issued by CBSE) UNIT VI : REPRODUCTION in Flowering Plants Term-I



Topic 1. Sexual Reproduction



Topic 2. Pollination and Fertilization



Topic 3. Post-fertilization Changes and



32 - 58



Topic 2. Drugs and Adolescence Topic 1. Microbes-in Household Products, Industrial Products and in



Reproduction System

Topic 2. Gametogenesis and Menstrual Cycle



Topic 3. Fertilization and

Sewage Treatment and Biogas

Topic 2. Microbes as Biocontrol







Topic 1. Health and Related Aspects, Common Human Diseases and Immunity



Special Modes of Reproduction

Topic 1. Male and Female





7. Microbes in Human Welfare Term-II 162 - 176

2. Human Reproduction Term-I

6. Human Health and Diseases Term-II 137 - 161

1 - 31

in flowering plants



Agents and Bio Fertilisers

UNIT IX : BIOTECHNOLOGY AND ITS APPLICATIONS

Post-Fertilization Events

8. Biotechnology :

3. Reproductive Health Term-I

59 - 68

UNIT VII : GENETICS AND EVOLUTION 4. Principles of Inheritance



Principles and Process Term-II



Topic 1. Principles of Biotechnology and Tools





and Variation Term-I



Topic 1. Mendelian Laws of Inheritance

69 - 103



Topic 2. Process of Recombinant



DNA Technology

and Chromosomal Theory

9. Biotechnology and its



of Inheritance

Applications Term-II

Topic 2. Sex Determination and



Chromosomal Disorder

5. Molecular Basis of Inheritance Term-I

Topic 1. Nucleic Acid – DNA and RNA



Topic 2. Genetic Code, Translation,



Lac operon, Human Genome



Project and DNA Fingerprinting

196 - 207



Topic 1. Application of Biotechnology in



Agriculture and Medicine



104 - 136

177 - 195

of Recombinant DNA Technology



15 - 37 38 - 60 61 - 71

UNIT VIII : BIOLOGY AND HUMAN WELFARE

1. Sexual Reproduction

8 - 13

Topic 2. Transgenic Animals



and Bioethical Issues

UNIT X : ECOLOGY & ENVIRONMENT 10. Organisms and Population Term-II 208 - 225

Topic 1. Organisms and its Environment



Topic 2. Population and Population Interactions

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TABLE OF CONTENTS 11. Biodiversity and its Conservation Term-II

226 - 239



Topic 1. Biodiversity and Its Patterns



Topic 2. Conservation of Biodiversity



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LET THE ADVENTURE BEGIN! India is currently one of the youngest economies in the world. Hence, it’s imperative for our education system to churn out more learners than ever before. It is this ‘learner’s mindset’ which will set

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Our Heartfelt Gratitude! e have taken due care in developing this book. There have been a lot of people who have helped W us in our journey. We would like to offer heartfelt gratitude to them- our authors, editors, reviewers, and especially students like you who regularly send us suggestions which help us in continuous improvement of this book. Here are the names of the students who have helped us make this book better: 1. Preeti from Indore

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CBSE CIRCULAR 2021-22 dsUæh; ek/;fed f'k{kk cksMZ

CENTRAL BOARD OF SECONDARY EDUCATION

NO.: F.1001/CBSE-Acad/Curriculum/2021

Date: July 22, 2021 Circular No: Acad- 53/2021

All the Heads of Schools affiliated to CBSE Subject:

Term wise syllabus for Board Examinations to be held in the academic session 2021-22 for Secondary and Senior Secondary classes and guidelines for the conduct of the Internal Assessment/Practicum/Project.

This is in continuation to Board’s circular number Acad 51/2021 dated July 05, 2021 regarding Special Scheme of Assessment for Board Examination for Classes X and XII for the Session 2021- 22. The syllabus for the two terms mentioned in the scheme in all subjects for classes IX to XII are hereby notified vides this circular. In addition to syllabus for term end board examinations, guidelines for the conduct of Internal Assessment/Practicum/Project are also enclosed. Schools are requested to share the term wise syllabus and guidelines for the conduct of board examinations and Internal Assessment / Practicum / Project available on CBSE Academic Website http://www.cbseacademic.nic.in at the link http://cbseacademic.nic.in/Term-wise-curriculum_2022.html with all their teachers and students.

(Dr. Joseph Emmanuel)

Director (Academics)

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SYLLABUS Latest BIOLOGY (Code No. 044) CLASS–XII (Theory) Time : 3 Hours

Max. Marks : 100

Evaluation Scheme Units No.

Term – I

Marks

VI

Reproduction: Chapter - 2, 3 and 4

15

VII

Genetics and Evolution: Chapter – 5 and 6

20

Units No. VIII

Term – II Biology and Human Welfare: Chapter – 8 and 10

14

IX

Biotechnology and its Applications: Chapter – 11 and 12

11

X

Ecology and Environment: Chapter – 13 and 15

10

Total Theory (Term – I and Term – II)

70

Practicals Term – I

15

Practicals Term – II

15

Total

100

THEORY : TERM - I UNIT - VI : REPRODUCTION Chapter-2: Sexual Reproduction in Flowering Plants Flower structure; development of male and female gametophytes; pollination - types, agencies and examples; outbreeding devices; pollen-pistil interaction; double fertilization; post fertilization events - development of endosperm and embryo, development of seed and formation of fruit; special modesapomixis, parthenocarpy, polyembryony; Significance of seed dispersal and fruit formation. Chapter-3 : Human Reproduction Male and female reproductive systems; microscopic anatomy of testis and ovary; gametogenesis spermatogenesis and oogenesis; menstrual cycle; fertilisation, embryo development upto blastocyst formation, implantation; pregnancy and placenta formation (elementary idea); parturition (elementary idea); lactation (elementary idea). Chapter-4 : Reproductive Health Need for reproductive health and prevention of Sexually Transmitted Diseases (STDs); birth control - need and methods, contraception and medical termination of pregnancy (MTP); amniocentesis; infertility and assisted reproductive technologies - IVF, ZIFT, GIFT (elementary idea for general awareness).

UNIT - VII : GENETICS AND EVOLUTION Chapter-5: Principles of Inheritance and Variation Heredity and variation: Mendelian inheritance; deviations from Mendelism – incomplete dominance, co-dominance, multiple alleles and inheritance of blood groups, pleiotropy; elementary idea of polygenic (9)

SYLLABUS inheritance; chromosome theory of inheritance; chromosomes and genes; Sex determination - in human being, birds and honey bee; linkage and crossing over; sex linked inheritance - haemophilia, colour blindness; Mendelian disorders in humans -thalassemia; chromosomal disorders in humans; Down’s syndrome, Turner’s and Klinefelter’s syndromes. Chapter-6: Molecular Basis of Inheritance Search for genetic material and DNA as genetic material; Structure of DNA and RNA; DNA packaging; DNA replication; Central Dogma; transcription, genetic code, translation; gene expression and regulation lac operon; Genome, Human and rice genome projects; DNA fingerprinting.

THEORY : TERM - II UNIT - VIII BIOLOGY AND HUMAN WELFARE Chapter-8: Human Health and Diseases Pathogens; parasites causing human diseases (malaria, dengue, chikungunya, filariasis, ascariasis, typhoid, pneumonia, common cold, amoebiasis, ring worm) and their control; Basic concepts of immunology vaccines; cancer, HIV and AIDS; Adolescence - drug and alcohol abuse. Chapter-10: Microbes in Human Welfare Microbes in food processing, industrial production, sewage treatment, energy generation and microbes as bio-control agents and bio-fertilizers. Antibiotics; production and judicious use.

UNIT - IX : BIOTECHNOLOGY AND ITS APPLICATIONS Chapter-11: Biotechnology - Principles and Processes Genetic Engineering (Recombinant DNA Technology). Chapter-12: Biotechnology and its Application Application of biotechnology in health and agriculture: Human insulin and vaccine production, stem cell technology, gene therapy; genetically modified organisms - Bt crops; transgenic animals; biosafety issues, biopiracy and patents.

UNIT - X : ECOLOGY AND ENVIRONMENT Chapter-13: Organisms and Populations Organisms and environment: Habitat and niche, population and ecological adaptations; population interactions - mutualism, competition, predation, parasitism; population attributes - growth, birth rate and death rate, age distribution. Chapter-15: Biodiversity and its Conservation Biodiversity - Concept, patterns, importance; loss of biodiversity; biodiversity conservation; hotspots, endangered organisms, extinction, Red Data Book, Sacred Groves, biosphere reserves, national parks, wildlife, sanctuaries and Ramsar sites.

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SYLLABUS PRACTICALS

Time allowed : 3 Hours

Max. Marks: 15 for each Term Evaluation Scheme TERM - I

TERM - II

Marks

Part A One Major Experiment

Experiment No. – 1

Experiment No. - 3

4

One Minor Experiment

Experiment No. - 2

Experiment No. – 4, 5

3

B.6, 7, 8

3

Part B Spotting

B.1, 2, 3, 4, 5

(3 Spots of 1 mark each) Practical Record + Investigatory Project &Record + Viva Voce

5

Total

15



Practicals should be conducted alongside the concepts taught in theory classes. A. List of Experiments TERM - I: 1. Isolate DNA from available plant material such as spinach, green pea seeds, papaya, etc. 2. Prepare a temporary mount to observe pollen germination. TERM - II: 3. Prepare a temporary mount of onion root tip to study mitosis. 4. Collect water from two different water bodies around you and study them for pH, clarity and presence of any living organism 5. Collect and study soil from at least two different sites and study them for texture, moisture content, pH and water holding capacity. Correlate with the kinds of plants found in them. B. Study/observation of the following (Spotting) TERM - I: B.1 Flowers adapted to pollination by different agencies (wind, insects, birds). B.2 Identification of stages of gamete development, i.e., T.S. of testis and T.S. of ovary through permanent slides (from grasshopper/mice). B.3 Meiosis in onion bud cell or grasshopper testis through permanent slides. B.4 T.S. of blastula through permanent slides (Mammalian). B.5 Prepared pedigree charts of any one of the genetic traits such as rolling of tongue, blood groups, ear lobes, widow’s peak and colourblindness. TERM – II: B.6 Common disease - causing organisms like Ascaris, Entamoeba, Plasmodium, any fungus causing ringworm through permanent slides, models or virtual images. Comment on symptoms of diseases that they cause. B.7 Two plants and two animals (models/virtual images) found in xeric conditions. Comment upon their morphological adaptations. B.8 Two plants and two animals (models/virtual images) found in aquatic conditions. Comment upon their morphological adaptations.

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SYLLABUS PRACTICAL EXAMINATION FOR VISUALLY IMPAIRED STUDENTS OF CLASSES XI AND XII EVALUATION SCHEME Max. Marks: 15 for each Term

Topic

Marks

Identification/Familiarity with the apparatus

5

Written test (Based on given/prescribed practicals)

5

Practical Records and Viva

5 Total

15

General Guidelines The practical examination will be of one-hour duration.

l

The written examination in practicals for these students will be conducted at the time of practical examination of all other students.

l l

The written test will be of 30 minutes duration.

l

The question paper given to the students should be legibly typed. It should contain a total of 8 practical skill based very short answer type questions. A student would be required to answer any 5 questions.

l

A writer may be allowed to such students as per CBSE examination rules.

l

All questions included in the question paper should be related to the listed practicals. Every question should require about two minutes to be answered.

l

These students are also required to maintain a practical file. A student is expected to record the listed experiments Term -wise as per the specific instructions for each subject. These practicals should be duly checked and signed by the internal examiner.

l

The format of writing any experiment in the practical file should include aim, apparatus required, simple theory, procedure, related practical skills, precautions etc.

l

Questions may be generated jointly by the external/internal examiners and used for assessment.

l

The viva questions may include questions based on basic theory/principle/concept, apparatus/materials/ chemicals required, procedure, precautions, sources of error etc.

Practicals should be conducted alongside the concepts taught in theory classes. A. Items for Identification/ familiarity with the apparatus for assessment in practicals (All experiments) TERM -I: l

Beaker, flask, petri plates, test tubes, aluminium foil, paint brush, bunsen burner/spirit lamp/water bath.

l

Starch solution, iodine, ice cubes.

l

Developmental stages of frog highlighting morula and blastula.

TERM -II: l

Soil from different sites- sandy, clayey, loamy; Small potted plants, Cactus/Opuntia (model), Large flowers, Maize inflorescence.

l

Model of Ascaris

B. List of Practicals TERM -I: 1. Study of flowers adapted to pollination by different agencies (wind, insects). 2. Identification of T.S of morula or blastula of frog (model). ( 12 )

SYLLABUS 3. Preparation of pedigree charts of genetic traits such as rolling of tongue, colour blindness. TERM -II: 4. Study of the soil obtained from at least two different sites for their texture. 5. Identify common disease-causing organisms like Ascaris (Model) and learn some common symptoms of the disease that they cause. 6. Comment upon the morphological adaptations of plants found in xerophytic conditions. Note: The above practicals may be carried out in an experiential manner rather than recording observations. Prescribed Books: 1. Biology, Class-XII, Published by NCERT 2. Other related books and manuals brought out by NCERT (including multimedia) 3. Biology Supplementary Material (Revised). Available on CBSE website.

ASSESSMENT AREAS (THEORY) 2021-22 CLASS XII BIOLOGY (044) Competencies Demonstrate Knowledge and Understanding

50%

Application of Knowledge / Concepts

30%

Analyse, Evaluate and Create

20%

Note: l Internal choice would be provided. Suggestive verbs for various competencies l Demonstrate, Knowledge and Understanding State, name, list, identify, define, suggest, describe, outline, summarize, etc. l Application of Knowledge/Concepts Calculate, illustrate, show, adapt, explain, distinguish, etc. l Analyze, Evaluate and Create Interpret, analyse, compare, contrast, examine, evaluate, discuss, construct, etc. qq





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NEW TYPOLOGIES INTRODUCED BY CBSE FOR BOARD 2022 EXAM UNIT-VI Reproduction

CHAPTER 1 - SEXUAL REPRODUCTION IN FLOWERING PLANTS TOPIC-1

Sexual Reproduction in Flowering Plants which is the most resistant organic material known. 1

Assertion & Reason

Direction : In the following questions, a statement of Assertion (A) is followed by a statement of Reason (R). Mark the correct choice as :



(a) Both assertion (A) and reason (R) are true and (R) is correct explanation of assertion (A).



(b) Both assertion (A) and reason (R) are true, but reason (R) is not the correct explanation of assertion (A).



(c) Assertion (A) is true, but reason (R) is false.



(d) Assertion (A) is false, but reason (R) is true.

Q. 1. Assertion (A) : Pollen grains are best preserved as fossils.

Reason (R) : The sporopollenin of exine is highly resistant to the action of strong acids and alkali and can withstand a high temperature.

Ans. (a)

Q. 2. Assertion (A) : Tapetum is formed during the process of the formation of microsporangium.

Reason (R) : The play an important role in guiding the pollen tubes into the synergid.

Ans. (c)

Explanation : Assertion is true, but the reason is wrong because tapetum plays an important role in nourishing pollen mother cells (PMCs) or microspores. 1

Q. 3. Assertion (A) : Flowers are structure of sexual reproduction.

Reason (R) : Different type of embryological process occur inside the flower.

Ans. (a)

Explanation : Pollen grains are well preserved as fossils because of the presence of sporopollenin

Explanation : Sexual reproduction involves the transfer fusion of male and female gametes known as pollination. The fertilized ovules produce seeds that continue the next generation. 1

TOPIC-2

Pollination and Fertilization Assertion & Reason

Direction : In the following questions a statement of Assertion (A) is followed by a statement of Reason (R). Mark the correct choice as :



(a) Both assertion (A) and reason (R) are true and (R) is correct explanation of assertion (A).



(b) Both assertion (A) and reason (R) are true, but reason (R) is not the correct explanation of assertion (A).



(c) Assertion (A) is true, but reason (R) is false.



(d) Assertion (A) is false, but reason (R) is true.

Q. 1. Assertion (A) : Entomophilous flowers are large, colourful, fragrant and rich in nectar.

Reason (R) : If helps in attracting the pollinating agent.

Ans. (a)

Explanation : Entomophily is a type of pollination, which is carried out by insects fragrance and colour of the flower’s attract insects. 1

Q. 2. Assertion (A) : In Ophrys one petal of the flower bears on an uncanny resemblance to the female bee.