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Biology

11

V.K. KhoslaKanta Khosla

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BIOLOGY

CLASS–XI (Theory)Time: 3 Hours 70 Marks

Unit No. Title No. of Periods Marks

I Diversity of Living Organisms 23 07

II Structural Organisation in Plants and Animals 22 11

III Cell : Structure and Function 35 15

IV Plant Physiology 40 17

V*Human Physiology (A) - Section for OTBA

Human Physiology (B)40 *10+10

Total 160 70

Note: The question paper of the year end examination to be held in the March 2017 will include a Section on Open Text Based Assessment (OTBA) which will include questions of a total of 10 marks. No other questions will be asked from the section of the unit earmarked for OTBA. The open text material will be supplied in advance. This material is designed to assess the analytical and higher order thinking skills of students.

*This section will be assessed through OTBA only.

Unit-I : Diversity of Living Organisms (23 Periods)

Chapter-1 : The Living World What is living?Biodiversity;Needforclassification;Threedomainsof life; taxonomyandsystematics;Conceptof

species and taxonomical hierarchy; Binomial nomenclature; tools for study of taxonomy–museums, zoological Parks, Herbaria, Botanical gardens.

Chapter-2 : Biological Classifi cation Fivekingdomclassification;SalientfeaturesandclassificationofMonera;ProtistaandFungiintomajorgroups;Lichens;

Viruses and Viroids. Chapter-3 : Plant Kingdom Salient features and classification of plants intomajor groups - Algae, Bryophyta, Pteridophyta, Gymnospermae

andAngiospermae(threetofivesalientanddistinguishingfeaturesandat leasttwoexamplesofeachcategory);Angiosperms-classificationuptoclass,characteristicfeaturesandexamples.

Chapter-4 : Animal Kingdom Salientfeaturesandclassificationofanimalsnon-chordateuptophylalevelandchordatesuptoclasslevel(threeto

fivesalientfeaturesandatleasttwoexamplesofeachcategory). (No live animals or specimen should be displayed.)

SYLLABUS

Unit-II : Structural Organisation in Animals and Plants (22 Periods) Chapter-5 : Morphology of Flowering Plants Morphologyandmodifications:Tissues. Chapter-6 : Anatomy of Flowering Plants Anatomyandfunctionsofdifferentpartsoffloweringplants:root,stem,leaf,inflorescence,flower,fruitandseed(to

be dealt along with the relevant experiment of the Practical Syllabus). Chapter-7 : Structural Organisation in Animals Animal tissues: morphology, anatomy and functions of different systems (digestive, circulatory, respiratory, nervous and

reproductive) of an insect (cockroach). (a brief account only).

Unit-III : Cell : Structure and Function (35 Periods) Chapter-8 : Cell - The Unit of Life Cell theory and cell as the basic unit of life; Structure of prokaryotic and eukaryotic cells; Plant cell and animal cell;

Cell envelope, cell membrane, cell wall; Cell organelles – structure and function; endomembrane system; endoplasmic reticulum,Golgibodies,lysosomes,vacuoles;mitochondria,ribosomes,plastids,microbodies;cytoskeleton,cilia,flagella,centrioles (ultrastructure and function); nucleus, nuclear membrane, chromatin, nucleolus.

Chapter-9 : Biomolecules Chemical constituents of living cells: biomolecules, structure and function of proteins, carbohydrates, lipids, nucleic acids;

enzymes, types, properties, enzyme action. Chapter-10 : Cell Cycle and Cell Division Cellcycle,mitosis,meiosisandtheirsignificance.

Unit-IV : Plant Physiology (40 Periods) Chapter-11 : Transport in Plants Movement of water, gases and nutrients; Cell to cell transport; Diffusion, facilitated diffusion, active transport; Plant-

water relations; Imbibition, water potential, osmosis, plasmolysis; Long distance transport of water – Absorption, apoplast, symplast, transpiration pull, root pressure and guttation; Transpiration; Opening and closing of stomata; Uptake and translocation of mineral nutrients – Transport of food, phloem transport, Massflow hypothesis; Diffusion of gases.

Chapter-12 : Mineral Nutrition Essential minerals, macro- and micronutrients and their role; Deficiency symptoms; Mineral toxicity; Elementary idea

of Hydroponics as a method to study mineral nutrition; Nitrogen metabolism; Nitrogen cycle, biological nitrogen fixation.

Chapter-13 : Photosynthesis in Higher Plants Photosynthesis as a mean of Autotrophic nutrition; site of photosynthesis, pigments involved in photosynthesis

(elementary idea); Photochemical and biosynthetic phases of photosynthesis; Cyclic and non-cyclic photophosphory-lation; Chemiosmotic hypothesis; Photorespiration; C3 and C4 pathways; Factors affecting photosynthesis.

Chapter-14 : Respiration in Plants Exchange of gases; Cellular respiration – glycolysis, fermentation (anaerobic), TCA cycle and electron transport

system (aerobic); Energy relations – Number of ATP molecules generated; Amphibolic pathways; Respiratory quotient.

Chapter-15 : Plant Growth and Development Seed germination; Phases of plant growth and plant growth rate; Conditions of growth; Differentiation,

dedifferentiation and redifferentiation; Sequence of developmental processes in a plant cell; Growth regulators –auxin, gibberellin, cytokinin, ethylene, ABA; Seed dormancy; Vernalisation; Photoperiodism.

Unit-V : Human Physiology (40 Periods) Part (A) will be asessed through OTBA whereas from the Part (B), there will be usual conceptual question in year

end examination.

Part (B) Chapter-16 : Digestion and Absorption Alimentary canal and digestive glands; Role of digestive enzymes and gastrointestinal hormones; Peristalsis, digestion,

absorptionandassimilationofproteins,carbohydratesand fats;Calorificvaluesofproteins,carbohydratesand fats;Egestion;Nutritionalanddigestivedisorders–PEM,indigestion,constipation,vomiting,jaundice,diarrhoea.

Part (B) Chapter-17 : Breathing and Exchange of Gases Respiratory organs in animals (recall only); Respiratory system in humans; Mechanism of breathing and its regulation in

humans – Exchange of gases, transport of gases and regulation of respiration, Respiratory volumes; Disorders related to respiration-Asthma, Emphysema, Occupational respiratory disorders.

Part (A) Chapter-18 : Body Fluids and Circulation Composition of blood, blood groups, coagulation of blood; Composition of lymph and its function; Human circulatory

system–Structureofhumanheartandbloodvessels;Cardiaccycle,cardiacoutput,ECG;Doublecirculation;Regulationof cardiac activity; Disorders of circulatory system - Hypertension, Coronary artery disease, Angina pectoris, Heart failure.

Part (B) Chapter-19 : Excretory Products and Their Elimination Modes of excretion – Ammonotelism, ureotelism, uricotelism; Human excretory system – structure and function; Urine

formation, Osmoregulation; Regulation of kidney function – Renin-angiotensin, Atrial Natriuretic Factor, ADH and Diabetes insipidus; Role of other organs in excretion; Disorders-Uraemia, Renal failure, Renal calculi, Nephritis; Dialysis andartificialkidney.

Part (B) Chapter-20 : Locomotion and Movement Typesofmovement–ciliary,flagellar,muscular;Skeletalmuscle–contractileproteinsandmusclecontraction;Skeletal

system and its functions; Joints; Disorders of muscular and skeletal system-Myasthenia gravis, Tetany, Muscular dystrophy, Arthritis,Osteoporosis,Gout.

Part (B) Chapter-21 : Neural Control and Coordination Neuron and nerves; Nervous system in humans – central nervous system, peripheral nervous system and visceral

nervous system; Generation and conduction of nerve impulse; Reflex action; Sensory perception; Sense organs;Elementary structure and functions of eye and ear.

Part (A) Chapter-22 : Chemical Coordination and Integration Endocrine glands and hormones; Human endocrine system - Hypothalamus, Pituitary, Pineal, Thyroid, Parathyroid,

Adrenal,Pancreas,Gonads;Mechanismofhormoneaction(ElementaryIdea);Roleofhormonesasmessengersandregulators,Hypoandhyperactivityandrelateddisorders;Dwarfism,Acromegaly,Cretinism,goiter,exophthalmicgoiter,diabetes, Addison’s disease.

Note : Diseases related to all the human physiological systems to be taught in brief.

QUESTION PAPER DESIGN

CLASS-XI

BIOLOGY (CODE NO. 044) Time-3 Hours Marks-70

S.

No.

Typology of Questions Very

Short

Answer

(VSA)

(1 Mark)

Short

Answer-I

(SA-I)

(2 Marks)

Short

Answer-II

(SA-II)

(3 Marks)

Value

Based

Question (VBQ)

(4 Marks)

Long

Answer (LA)

(5 Marks)

Total

Marks

%

Weightage

1. Remembering—(Knowledge

based Simple recall questions, to know specific facts, terms, concepts, principles, or theories, Identify, define, or recite, information)

2 1 1 – – 7 10%

2. Understanding Comprehension—(to be familiar with meaning and to understand conceptually, interpret, compare, contrast, explain, paraphrase, information).

– 2 4 – 1 21 30%

3. Application—(Use abstract information in concrete situation, to apply knowledge to new situations, Use given content to interpret a situation, provide an example, or solve a problem).

– 2 4 – 1 21 30%

4. Higher Order Thinking Skills (Analysis & Synthesis)—(Classify, compare, contrast, or differentiate between different pieces of information; Organize and/or integrate unique pieces of information from a variety of sources).

2 – 1 – 1 10 14%

5. Evaluation—(Appraise, judge, and/or justify the value or worth of a decision or outcome, or to predict outcomes based on values)

1 – 2 1 – 11 16%

TOTAL 5×1=5 5×2=10 12×3=36 1×4=4 3×5=15 70(26) 100%

Note : The question paper of the year end exmination to be held in the March 2017 will include a Section on Open Text Based Assessment (OTBA) which will include questions of a total of 10 marks (two questions of 5 marks each). No other questions will be asked from the section of the unit earmarked for OTBA. The open text material will be supplied in advance. This material is designed to test the analytical and higher order thinking skills of students.

QUESTION WISE BREAK UP

Type of Question Mark(s) per Question Total No. of Questions Total Marks

VSA 1 5 05

SA-I 2 5 10

SA-II 3 12 36

VBQ 4 1 04

LA 5 3 15

Total 26 70

1. Internal Choice: There is no overall choice in the paper. However, there is an internal choice in one question of 2 marks weightage, one question of 3 marks weightage and one question of 5 marks weightage (Content based question).

2. The above template is only a sample. Suitable internal variations may be made for generating similar templates keeping the overall weightage to different form of questions and typology of questions same.

C K

Super Refresher

Every chapter divided

into Sub-topics

All chapters as per

Syllabus and NCERT Textbooks

CBSE

NCERT Textbook

Questions with answers

C K

Additional

Important

Questions

with

answers

NCERT Exemplar

Problems

with answers

C K

C K

Biology SELF

EVALUATION

TEST

Model

(For Revision)

Practice Papers

HOTS

questions

with answers

in every chapter

Variety of

Value Based

Questions

CONTENTS

UNIT-1 : DIVERSITY IN LIVING ORGANISMS

1 The Living World 1 – 19

2 Biological Classification 20 – 40

3 Plant Kingdom 41 – 67

4 Animal Kingdom 68 – 98

UNIT-2 : STRUCTURAL ORGANISATION IN ANIMALS AND PLANTS

5 Morphology of Flowering Plants 100 – 144

6 Anatomy of Flowering Plants 145 – 174

7 Structural Organisation in Animals (Morphology of Animals and Animal Tissues) 175 – 208

UNIT-3 : CELL : STRUCTURE AND FUNCTIONS

8 The Cell : The Basic Unit of Life 210 – 250

9 Bimolecules 251 – 285

10 Cell Cycle and Cell Division 286 – 304

UNIT-4 : PLANT PHYSIOLOGY

11 Transport in Plants 306 – 331

12 Plant Nutrition 332 – 352

13 Photosynthesis in Higher Plants 353 – 380

14 Respiration in Plants 381 – 403

15 Plant Growth and Development 404 – 426

UNIT-5 : HUMAN PHYSIOLOGY

16 Digestion and Absorption 428 – 451

17 Breathing and Exchange of Gases 452 – 474

18 Body Fluids and Circulation 475 – 501

19 Excretory Products and Their Elimination 502 – 523

20 Locomotion and Movements 524 – 548

21 Neural Control and Co-ordination 549 – 581

22 Chemical Co-ordination and Integration (Endocrine System) 582 – 604

Model Question Papers (For Revision) 1 – 4

This unit includes the study of the following :

����� The Living World����� Biological Classification����� Plant Kingdom����� Animal Kingdom

DIVERSITY IN LIVING ORGANISMS

UNIT–1

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11The Living World

2

1.1 Characteristics of Life

Life can be defined as a unique, complex,

organization of molecules acquire and use energy for

metabolism, expressing itself through chemical

reactions which lead to growth, development,

responsiveness, adaptation and reproduction.

Aggregation, interaction, equilibrium and change

regulate all types of organisations.

�Cellular organisation of the body is the defining

feature of all living organisms.

� Group of cells meant to perform a specific function

is called tissue.

� Biological organisation starts with submicroscopic

molecular levels, passes through microscopic cellular

level and microscopic or macroscopic organismal level

and ends in ecosystems and biosphere.

�Growth. 1. The permanent increase in mass, weight

and volume due to internal changes is called growth.

2. It may be due to increase in number of cells or

living material.

3. In plants growth is unlimited and occurs

continuously throughout life and in specific regions.

4. In animals, growth is restricted to a certain

period only, but cell divisions occur in certain tissues

to replace the old and worn out cells. All parts of body

grow simultaneously.

� Reproduction. 1. The ability to produce young

ones of its own kind so that the species continue is

called reproduction.

2. Unicellular organisms reproduce by cell division,

usually mitosis.

3. In multicellular organisms, reproduction refers

to the production of young ones of the same kind.

4. Reproduction may be asexual or sexual.

5. Asexual reproduction is shown by lower groups

of animals like Hydra (budding), sponges (gemmules)

and Planaria (regeneration).

6. In many fungi, filamentous algae and protonema

of mosses, asexual / vegetative reproduction is by

fragmentation.

7. There are certain organisms like mule andworker honey bees, which are sterile and do notreproduce at all.

8. Sexual reproduction in animals involveformation and fusion of gametes.

Metabolism. 1. It is defining feature of livingorganisms.

2. It refers to the sum total of all the chemicalreactions occurring in a living body. Isolated metabolicreactions are not living things but surely they are

living reactions.

3. All living organisms are made up of small and

large chemical compounds, which carry out different

functions, they are constantly being synthesised and used.

4. Metabolism include both catabolism (breaking

down) and anabolism (building up).

� Ectothermic and endothermic organism.

In living organisms thermal energy is produced during

energetic reactions. The ectothermic animals such as fish,

amphibians, reptiles and plants. Mammals, birds and a

few fishes instead of losing thermal energy retain it. They

are termed endothermic.

� Homoeostasis. Living organisms maintain their

internal organisation stable irrespective of changes

in the environment. It is termed homeostasis.

� Living systems are open systems.

� Consciousness is the defining property of living

organisms.

1.1. What is living ? Characteristics of life : Growth, Cellular organisation, Reproduction,Metabolism, Consciousness.

1.2. Biodiversity.1.2.1.Need and scope of taxonomy, History of taxonomy, Identification,

nomenclature.1.2.2.Taxonomic hierarchy

1.3. Taxonomic aids :Herbarium, Botanical gardens, Zoological Parks, Museum and Keys.

CONCEPTS

ch1.pmd 9/27/2016, 4:19 PM2

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3The Living World

1 Define a life.

Ans. Life is unique, complex, organisation of

molecules expressing itself through chemical

reactions which lead to growth, development,

responsiveness, adaptation and reproduction.

2 Define growth and development.

Ans. Growth. Permanent increase in mass or

overall size of a tissue or organism or its

parts is called growth.

Development. The formation of young one

from a fertilized egg or zygote is called

development.

3 What is reproduction ?

Ans. Reproduction. It is production of young

ones of its own kind.

4 What is metabolism ?

Ans. The sum total of all chemical reactions

occurring in an organism due to specific

interactions amongst different types of

molecules within the interior of cell is called

metabolism.

5 What is organisation ?

Ans. Organisation is the arrangement of smaller

components of any structure, system or

situation into larger ones and the larger ones

into still larger ones in a hierarchy, where

components of each level coordinate with one

another towards a common goal.

6 Name two ectothermic animals.

Ans. Fish (Scoliodon), Amphibians (Frog).

7 Can we relate metabolism with growth

of body ?

Ans. Metabolism is comprised of anabolism and

catabolism while growth occur when quantity

of anabolic reactions exceeds the quantity of

catabolic reaction.

8 How do living things grow ?

Ans. Living organisms grow either by repeated cell

divisions or by increase in cell mass.

9 What is the advantage of consciousness

in living organisms ?

Ans. The property of conciousness of living

organisms enables them to respond to external

factors physical, chemical or biological stimuli.

10 Is reproduction definning char-

acteristics of living organism ?

Ans. Yes, however a few organisms such as sterile

worker bees, mules etc. do not breed.

1.2 Biodiversity

� Living organisms respond to stimuli

1. All living organisms respond to stimuli. It is the

important character to distinguish livinig being from

non-living.

2. All organisms, prokaryotes or eukaryotes, simple

or complex in organisation, have the ability to sense

the conditions in their surroundings and respond to

these stimuli.

3. Such stimuli may be physical, chemical or

biological.

4. Photoperiod affects reproduction in several

seasonal breeders of animals as well as flowering in

plants.

5. Stems of plants bend towards light, while roots

bend towards water sources and gravitational pull.

� There are innumerable plants, animals, bacteria

and viruses. Each one differs from the other.

� Biological classification is art of identifying

distinction among organisms and placing them into

groups.

� There is a great diversity among living organisms

termed biodiversity.

� About 1.7 million species are known and many

more species are believed to exist. Insects cover the

largest group with more than 7,50,000 known existing

species.

� Many species lived in the past and are found in

the fossil forms.

� Ernst Mayr (1904-2004) has been called ‘Darwin

of 20th Century.’

� Classification allows subsequent identification

of a species.

� Artificial, Natural and phylogenetic are the main

systems of classification.

1.2.1 Scope of Taxonomy

� G . S i m p s o n (1961) defined taxonomy,

classification and systematics separately.

� He regards classification as subtopic of

systematics that deals with ordering of organisms.

� Systematics is regarded as study of diversity of

organisms and all their comparative and evolutionary

relationship.

� Taxonomy deals with principles and procedure

of classification.

ch1.pmd 9/27/2016, 4:19 PM3

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4 MBD Super Refresher Biology-XI

� Characterisation, identification, classification andnomenclature are processes that are basic totaxonomy.

� The unit of classification is species.

� There is a record of the 740 plants and 250 animalsin our vedic culture.

� Hippocrates and Aristotle arranged animalsinto four groups i.e. insects, fishes, birds and whales.

� A species is defined as a group of closelyresembling organisms, freely interbreeding amongstthemselves, produce young ones of their own kind andhave descended from common ancestor.

Carl Linnaeus introduced the binomialnomenclature. In binomial nomenclature, the nameof organism consists of two words, the first word refersto the generic name (name of genus) and second thespecific name (name of species). Rana tigrina is thescientific name of common Indian frog.

1.2.2 Taxonomic hierarchy

During classification, species are recognized,

named and grouped into genera on the basis of

common characters. Similarly, genera are grouped into

a family, similar families into an order, similar orders

into a class, similar classes in a phylum and finally

similar phyla into a kingdom.

� Recommendations for formulating new

names for organisms.

While formulating new names for organisms, thefollowing suggestions are kept in mind :

1. The name should be in Latin or easily convertibleinto Latin form.

2. They should not be composed of less than threeletters or more than twelve letters.

3. The name should be easy to pronounce.

4. The name should refer to some important featureof the organism.

5. A name should not be derived from twolanguages.

6. A name should not be unimportant.

7. Type specimen. A specimen on the descriptionof which species name is established.

Advantages of scientific names

1. Specific names are international irrespective oflanguage of the people.

2. Scientific names are descriptive and representsome important features of organisms.

3. These names show the relationship of oneorganism with the other.

4. Scientific names have mostly been taken from

Greek and Latin languages and there is little scope

for the modification in the use of these names.

� Each category is considered a taxonomic unit and

represents taxon.

� ICBN = International Code for Botanical

Nomenclature

� ICZN = International Code for Zoological

Nomenclature

1 Define systematics.

Ans. Arrangement of organisms into anappropriate system is termed systematics.

2 Name the 3 main systems of classi-fication.

Ans. Artificial, natural and phylogenetic.

3 Who devised the binomial nomenclature ?

Ans. Carolus Linnaeus.

4 What is a type specimen ?

Ans. On the description of which species name isestablished.

5 Give the number and names ofobligatory taxonomic categories.

Ans. Seven.

Kingdom, phylum, class, order, family, genus

and species.

6 Define a taxon.

Ans. A group of similar genetically related

individuals.

7 What does the abbreviation ICZN stand

for ?

Ans. International Code of Zoological Nomen-

clature.

8 Why the scientific names are derived

from latin or are latinized ?

Ans. Latin is a dead language, therefore there is

little likelihood of changes in meaning and

spelling of names with time.

9 Write the full form of ICBN.

Ans. International Code of Botanical Nomen-

clature.

10 Write three codes of nomenclature.

Ans. (i) International Code of Botanical

Nomenclature (ICBN) (ii) International Code

of Zoological Nomenclature (ICZN) and (iii)

International Code of Bacteriological

Nomenclature.

11 Why new names are derived from latinor are latinized ?

Ans. This is because Latin language is dead and,

therefore, it will not change in form or

spelling with the passage of time.

ch1.pmd 9/27/2016, 4:19 PM4

MBD CBSE Super Refresher BiologyFor Class 11

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Author : VK Khosla AndKanta Khosla

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