NCERT Solutions for Class 11 Biology

Download Chapter wise NCERT Solutions for Class 11 Biology

NCERT Solutions Class 11 Biology is one of the most comprehensive study materials available to students studying for exams. It thoroughly answers all of the important questions. In addition, all answers are provided in an easy-to-understand manner. Students can simply obtain the NCERT Solutions because they are in PDF format. Professors design solutions that are simple to comprehend in order to aid students in their exam preparation. They usually help students identify and address areas of weakness so that they can enhance their grades. Students will be able to use these solutions to answer all of the questions from the NCERT Textbook.

Students struggle to find appropriate study materials that fit their needs. To address the demands of students, Infinity Learn offers chapter-by-chapter solutions in both online and offline forms. For students in Class 11 who are working hard to attain their career goals, the NCERT Solutions for Class 11 is an excellent resource. As a result, we’ve organised these solutions so that students will have no trouble grasping and remembering crucial topics.

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    You would normally read a concept and try to recall it. You must memorize the topic even if you do not understand it because it is a vital part of your exam. The prescribed responses are rewritten in an easy-to-understand and recall language, which is where these solutions come in. After analyzing the average mental competency of Class 11 students, a team of highly experienced specialists devised the curriculum. This leads to content that is targeted exclusively at students, making it simple to grasp the subject completely.

    To get a head start on your test preparations, download the Class 11 NCERT Solutions for Biology.

    NCERT Solutions for Class 11 Biology Chapter wise:

    NCERT Solutions Class 11 Biology is a useful resource for entrance exams such as NEET, JEE, medical entrance exams, and a range of other competitive exams. Experts at Infinity Learn created these solutions to help students grasp the most information with the least amount of mental work.

    It consists of straightforward responses written in a straightforward manner. Students may acquire NCERT Solutions for Class 11 Biology for each chapter and unit in the biology textbooks rapidly. These solutions include topics including biological taxonomy, animal and plant kingdoms, morphology, structural organization, biomolecules, cell division, plant transport, nutrition, photosynthesis, and more.


    NCERT Solutions Class 11 Biology Chapter Details and Exercises

    Chapter 1: The Living World – Term I

    The fundamental concepts of “What is Living?” and “What is Death?” are explored in greater depth in this chapter. There are discussions about taxonomic categories, taxonomic aids, and other topics. The living world is full of variety. Millions of plant and animal species have been recognized and documented up to this point, but there are yet millions more to uncover. Taxonomic studies of a wide range of plant and animal species are useful in agriculture, forestry, industry, and a general understanding of our resources and diversity. To aid in the identification, naming, and categorization of organisms, taxonomists have developed a number of taxonomic aids.

    The following subjects were discussed:

    What does it mean to be alive? Biodiversity; categorization; taxonomy and systematics; species idea and taxonomic hierarchy; binomial nomenclature; Museums, zoological parks, herbaria, botanical gardens, and keys for identification are some of the places where you can learn about taxonomy.

    Chapter 2: Biological Classification – Term I

    In this chapter, we’ll look at the properties of the Whittaker system’s Kingdoms Monera, Protista, and Fungi. Plantae and Animalia, often known as the plant and animal kingdoms, will be explored individually in Chapters 3 and 4. As part of the biological classification, you’ll study Kingdom Monera, Kingdom Protista, Kingdom Fungi, Kingdom Plantae, Kingdom Animalia, Viruses, Viroids, and Lichens.

    The following subjects were discussed:

    Lichens, Viruses, and Viroids; Five kingdom classification; Monera, Protista, and Fungi into key groups; Lichens, Viruses, and Viroids.

    Chapter 3: Plant Kingdom – Term I

    In the last chapter, we looked at the basic classification of living species, which was based on Whittaker’s (1969) Five Kingdom classification, which includes the kingdoms Monera, Protista, Fungi, Animalia, and Plantae. We’ll go through more classification within the Kingdom Plantae, generally known as the ‘plant kingdom,’ in this chapter. Algae, Bryophytes, Pteridophytes, Gymnosperms, Angiosperms, Plant Life Cycles, and Generations Alternation are among the topics covered.

    The following subjects were discussed:

    Plants are classified into four primary groups: Algae, Bryophyta, Pteridophyta, Gymnospermae, and Angiospermae (salient and distinctive traits, as well as a few examples of each category): Angiosperms – categorization, characteristics, and examples up to class. Plantlife cycles and generational changes.

    Chapter 4: Animal Kingdom – Term I

    When we look around, we find a diversity of animals with different structures and forms. With more than a million animal species identified to date, taxonomy becomes even more important. Categorization can also be used to assign a systematic position to newly reported species. It also includes sections on the Basis of Classification, Animal Classification, and other related issues. Students will learn a little about the animal kingdom in this chapter.

    The following subjects were discussed:

    Non-chordates up to phylum level and chordates up to class level are classified on the basis of their conspicuous traits and classification (salient features and distinguishing features of a few examples of each category). (There should be no live animals or specimens on display in the classroom.)

    Chapter 5: Morphology of Flowering Plants – Term I

    Plant classification was explored in Chapters 2 and 3 based on morphological and other characteristics. Any attempt at classification and understanding of any higher plant requires the use of standard technical terms and definitions (or, for that matter, any living entity). We also need to know about potential changes in different parts as a result of plant adaptations to their environment, such as habitat adaptations, protection, climbing, and storage. Morphology of Flowering Plants covers the root, stem, leaf, inflorescence, flower, fruit, seed, semi-technical description of a typical flowering plant, description of several important families, and more.

    The following subjects were discussed:

    Diverse sections of flowering plants have different morphologies: root, stem, leaf, inflorescence, flower, fruit, and seed. Families are described as Fabaceae, Solanaceae, and Liliaceae are three families of plants (to be dealt with along with the relevant experiments of the Practical Syllabus).

    Chapter 6: Anatomy of Flowering Plants – Term I

    This chapter discusses the internal structure and functional organisation of higher plants. The study of a plant’s internal structure is known as anatomy. Plants are made up of cells that are organised into tissues, which are then organised into other plant components. Within angiosperms, monocots and dicots are physically distinct. Internal architecture can also be modified to fit a range of situations. Tissues, Tissue System, Dicotyledonous and Monocotyledonous Plant Anatomy, Secondary Growth, and other topics are discussed.

    The following topics were covered:

    Anatomy and functions of different tissues and tissue systems in dicots and monocots. Secondary growth.

    Chapter 7: Structural Organisation in Animals – Term I

    This chapter discusses the internal structure and functional organisation of higher plants. The study of a plant’s internal structure is known as anatomy. Plants are made up of cells that are organised into tissues, which are then organised into other plant components. Within angiosperms, monocots and dicots are physically distinct. Internal architecture can also be modified to fit a range of situations. Tissues, Tissue System, Dicotyledonous and Monocotyledonous Plant Anatomy, Secondary Growth, and other topics are discussed.

    The following topics were covered:

    Animal tissues; Morphology, Anatomy, and functions of different systems (digestive, circulatory, respiratory, nervous, and reproductive) of an insect-cockroach (a brief account only).

    Chapter 8: Cell – The Unit of Life – Term I

    When you look around, you can notice both live and non-living things. You must have pondered, “What is it that makes a creature live?” “What is it that a living thing has that an inanimate item doesn’t?” or “What is it that a living thing has that an inanimate item doesn’t?” The answer is that all living organisms contain the basic unit of life, the cell. Every living thing is made up of cells. The term “unicellular organism” refers to creatures that have only one cell. Others, like us, are multicellular beings, consisting of numerous cells.

    The following subjects were discussed:

    Plant and animal cells; cell envelope; cell membrane; cell wall; cell organelles – structure and function; endomembrane system – endoplasmic reticulum, ribosomes, Golgi bodies, lysosomes, vacuoles; mitochondria, plastids, microbodies; cytoskeleton, cilia, flagella, centrioles (ultrastructure and function); nucleus.

    Chapter 9: Biomolecules – Term I

    There are several living species in our biosphere. What Is the Best Way to Analyze Chemical Composition? This chapter also covers another topic. Biomacromolecules, Proteins, Polysaccharides, Nucleic Acids, Protein Structure, and Bond Nature are all examples of biomacromolecules. The Living State, Enzymes, Linking Monomers in a Polymer, Dynamic State of Body Constituents – Metabolism, Metabolic Basis for Living, The Living State Infinity Understand’s NCERT Solutions for Class 11 Biology Chapter 9 Biomolecules can help students learn more about these topics.

    The following subjects were discussed:

    Biomolecules, protein structure and function, carbohydrates, lipids, and nucleic acids, as well as the idea of metabolism, are chemical elements of living cells. Properties, enzyme activity, factors, classification, and co-factors are all terms used to describe enzymes.

    Chapter 10: Cell Cycle and Cell Division – Term II

    All living species, including cells, have the ability to grow and reproduce. Every cell splits into two daughter cells, with each parental cell dividing into two daughter cells. From the development and division of a single mother cell and her progeny, these newly formed daughter cells can grow and divide, culminating in the establishment of a new cell population. To put it another way, such growth and division cycles allow a single cell to grow into a complex containing millions of cells. Cell Cycle, M Phase, Mitosis Significance, Meiosis Significance, and Meiosis Significance are some of the other subtopics covered in the chapter.

    The following topics were covered:

    Cell cycle, mitosis, meiosis, and their significance.

    Chapter 11: Transport in Plants – Term II

    The chapter Transport in Plants covers themes such as means of transportation, plant-water relations, long-distance water transport, transpiration, mineral nutrient uptake, and transport, phloem, and transport: flow from source to sink. Plants acquire a variety of inorganic elements (ions) and salts from their surroundings, which include water and soil. Translocation is carried out by the vascular system of higher plants, which consists of the xylem and phloem. Phloem transports food (mostly sucrose) from the source to the sink. The translocation in phloem is explained by the pressure-flow concept.

    The following subjects were discussed:

    Plant-water relations, imbibition, water potential, osmosis, plasmolysis; long-distance water transport – 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, mass flow hypothesis.

    Chapter 12: Mineral Nutrition – Term II

    We’ll look at the methods for identifying components that are required for plant growth and development, as well as the criteria for defining essentiality, in this chapter, which focuses on inorganic plant nutrition. We’ll also look at the functions of key elements, as well as the most prevalent deficiency symptoms and how these elements are absorbed. In the chapter Mineral Nutrition, the importance and process of biological nitrogen fixation are briefly explored.

    The following subjects were discussed:

    Hydroponics is a method for studying mineral nutrition; necessary minerals, macro-and micronutrients, and their roles; deficient symptoms; Mineral toxicity; nitrogen metabolism, nitrogen cycle, and biological nitrogen fixation.

    Chapter 13: Photosynthesis in Higher Plants – Term II

    All species, including humans, rely only on plants for their survival. Green plants, often known as autotrophs, use photosynthesis to create or rather synthesize the food they require. Green plants employ light energy to promote the synthesis of organic molecules in a physicochemical process known as photosynthesis. Photosynthesis is significant for two reasons: it is the foundation of all known food chains on the planet, and it is the primary source of oxygen. It also oversees the release of oxygen into the atmosphere by green plants. This chapter covers the structure of the photosynthetic machinery as well as the several reactions that transform light energy into chemical energy.

    The following subjects were discussed:

    Early studies, photosynthesis sites, pigments involved in photosynthesis (basic principle); photochemical and biosynthetic stages of photosynthesis; cyclic and non-cyclic photophosphorylation; chemiosmotic hypothesis; photorespiration; C3 and C4 pathways; variables affecting photosynthesis.

    Chapter 14: Respiration in Plants – Term II

    This chapter discusses the mechanics of cellular respiration, or the breakdown of food components within the cell to release energy, and the trapping of this energy for the synthesis of ATP. “Do Plants Breathe?” is one of the questions addressed in this chapter. Glycolysis, Fermentation, Aerobic Respiration, The Respiratory Balance Sheet, Amphibolic Pathway, Respiratory Quotient, Res Fermentation, Aerobic Respiration, Glycolysis The Respiratory Balance Sheet. The important concepts of this chapter, Respiration in Plants, are explained in simple terms to enable Class 11 pupils to grasp them.

    The following subjects were discussed:

    cellular respiration – glycolysis, fermentation (anaerobic), TCA cycle, and electron transport system (aerobic); energy relations – number of ATP molecules generated; amphibolic pathways; respiratory quotient; exchange of gases; do plants breathe.

    Chapter 15: Plant Growth and Development – Term II

    We looked at the organisation of a flowering plant in Chapter 15. In this chapter, we’ll look at some of the components that govern and control these developmental processes. Both intrinsic (internal) and extrinsic (external) influences affect the plant. Other subtopics include Growth Differentiation, Dedifferentiation, and Redifferentiation, Development, Plant Growth Regulators, Photoperiodism, Vernalization, and others. Infinity Learn’s highly experienced professors have provided Plant Growth and Development answers to help students ace the final exam.

    The following subjects were discussed:

    Seed germination; plant growth characteristics, measurements, and phases, growth rate; growth conditions; differentiation, dedifferentiation, and redifferentiation; Auxin, gibberellin, cytokinin, ethylene, ABA; seed dormancy; vernalization; photoperiodism.

    Chapter 16: Digestion and Absorption

    Food is one of all living beings’ most fundamental necessities. The three basic components of a human diet are carbohydrates, proteins, and fats. Vitamins and minerals are also required in little doses. Food provides both energy and organic materials for tissue growth and repair. Water is essential for metabolic activities and aids in keeping the body hydrated. In their normal form, our bodies are unable to utilize biomacromolecules. They must be broken down and converted into simple components in the digestive system. The mechanical and biological reduction of complicated food components to simple absorbable forms that our digestive system performs is known as digestion. The chapter Digestion and Absorption provides a brief explanation to assist students to understand these concepts.

    The following subjects were discussed:

    The role of digestive enzymes and gastrointestinal hormones in the alimentary canal and digestive glands; Protein digestion, absorption, and assimilation are all part of peristalsis, carbohydrates, and fats; egestion; nutritional and digestive disorders – indigestion, constipation, vomiting, jaundice, diarrhea.

    Chapter 17: Breathing and Exchange of Gases – Term II

    As you may know, organisms obtain energy by breaking down simple molecules like glucose, amino acids, fatty acids, and so on with the help of oxygen. Carbon dioxide, which is poisonous, is also produced by the catabolic activities mentioned above. As a result, the cells must be supplied with oxygen on a continual basis, and the carbon dioxide produced by the cells must be evacuated. The process of exchanging oxygen from the atmosphere for carbon dioxide produced by the cells is known as breathing. Breathing is another name for it.

    The following subjects were discussed:

    Introduction to animal respiratory organs; Human respiratory system; Human breathing mechanism and regulation – exchange of gases, transport of gases and regulation of respiration, respiratory volumes; Respiratory disorders – asthma, emphysema, occupational respiratory disorders

    Chapter 18: Body Fluids and Circulation – Term II

    We’ve learned that nutrition, oxygen, and other necessary elements must be delivered to all living cells. Furthermore, in order for tissues to function properly, waste or toxic chemicals must be removed on a regular basis. In most higher species, including humans, blood is the most widely used bodily fluid. Lymph, another bodily fluid, aids in the movement of specific chemicals. We’ll look at the composition and properties of blood and lymph (tissue fluid) in this chapter, as well as the mechanics of blood circulation.

    The following topics were covered:

    Composition of the blood, blood groups, coagulation of blood; composition of lymph and its function; circulatory pathways; human circulatory system – Structure of human heart and blood vessels; cardiac cycle, cardiac output, ECG; double circulation; regulation of cardiac activity; disorders of the circulatory system – hypertension, coronary artery disease, angina pectoris, heart failure.

    Chapter 19: Excretory Products and their Elimination – Term II

    Human Excretory System, Urine Formation, Tubule Function, Filtrate Concentration Mechanism, Kidney Function Regulation, Micturition, Role of Other Organs in Excretion, Excretory System Disorders, and more are covered in this chapter.

    The following topics were covered:

    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, diabetes insipidus; micturition; the role of other organs in excretion; disorders – uremia, renal failure, renal calculi, nephritis; dialysis and artificial kidney, a kidney transplant.

    Chapter 20: Locomotion and Movement – Term II

    Movement is one of the most important properties of living creatures. Animals and plants have a number of ways to move. Such voluntary movements are referred to as locomotion. Walking, running, climbing, flying, and swimming are examples of locomotory movement. Structures that affect locomotion don’t have to be separated from those that affect other types of movement. Depending on their environments and the demands of the scenario, animals move in different ways. Food, shelter, a mate, good breeding grounds, favorable climatic conditions, and avoiding predators are all causes for mobility.

    The following subjects were discussed:

    Types of movement – amoeboid, ciliary, flagellar, muscular; types of muscles; skeletal muscle, contractile proteins, and muscle contraction; skeletal system and functions; joints; muscular and skeletal system disorders – myasthenia gravis, tetany, muscular dystrophy, arthritis, osteoporosis, and gout.

    Chapter 21: Neural Control and Coordination – Term II

    The process by which two or more organs interact and complement one another’s functions is known as coordination. The brain and endocrine systems in our bodies work together to coordinate and integrate all of the organs’ operations so that they work in unison. We will learn about the human neurological system, neural coordinating processes such as nerve impulse transmission, impulse conduction across a synapse, and the physiology of reflex response in this chapter.

    The following topics were covered:

    Neuron and nerves; Nervous system in humans – the central nervous system and peripheral nervous system; generation, conduction, and transmission of nerve impulse; reflex action; sensory perception; sense organs; elementary structure and functions of eye and ear.

    Chapter 22: Chemical Coordination and integration – Term II

    The neurological system enables fast point-to-point coordination between organs, as we already know. Neural coordination occurs quickly, but only for a short time. Because nerve fibers do not innervate every cell in the body and cellular activities must be constantly regulated, a special level of coordination and integration is necessary. Hormones are in charge of this process. To coordinate and regulate the body’s physiological activities, the neurological and endocrine systems collaborate. Infinity Learn’s NCERT Solutions might aid students in better understanding chemical coordination and integration.

    The following subjects were discussed:

    Human endocrine system – hypothalamus, pituitary, pineal, thyroid, parathyroid, thymus, adrenal, pancreas, gonads; hormones of the heart, kidney, and gastrointestinal tract; mechanism of hormone action (elementary idea); dwarfism, acromegaly, cretinism, goitre, exophthalmic goitre, diabetes, Addison’s disease.

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

    Learning about these topics can be challenging academically due to the large quantity of information contained in each concept. With these well-developed study guidelines, the experience becomes effective and interesting. Students can view and download the NCERT Class 11 Books on the internet.

    Because Infinity Learn is a learning organisation, we understand the significance of study materials and how they influence academic performance. As a result, we developed Class 11 NCERT Solutions for Biology, a learning resource designed to help students study and achieve their objectives.

    CBSE Marking Scheme 2021-22

    A student will take the board exams twice in their lives. One is in Class 10 and the other is in Class 12. Students’ grades in Class 10 help them understand the topics in which they excel, while their grades in Class 11 help them plan their future. In order to make it easier for students to study all of the concepts, the CBSE board has divided the entire syllabus into two terms. After studying the CBSE board’s revised course structure, students will be able to comprehend the chapters that are worth more marks and practice them effectively.

    Term I and Term II: CBSE Class 11 Biology Syllabus Course Structure 2021-22

    Units Title Marks
    I Diversity of Living Organisms 12
    II Structural Organization in Plants and Animals 12
    III Cell: Structure and Functions 12
    IV Plant Physiology 17
    V Human Physiology 17
    Total Theory 70
    Practical Term – I 15
    Practical Term – II 15
    Total 100

    Class 11 Biology NCERT Solutions

    A student will take the board exams twice in their lives. One is in Class 10 and the other is in Class 11. Students’ grades in Class 10 help them understand the topics in which they excel, while their grades in Class 11 help them plan their future. In order to make it easier for students to study all of the concepts, the CBSE board has divided the entire syllabus into two terms. After studying the CBSE board’s revised course structure, students will be able to comprehend the chapters that are worth more marks and practice them effectively.

    Benefits of Biology NCERT Solutions Class 11

    • Experienced teachers conducted research and wrote the solutions.
    • In each chapter, there are new value-based questions with answers.
    • Jargon-free and simple language.
    • The content has been created in accordance with the CBSE curriculum 2021-22.
    • The Coverage of essential ideas is extensive.
    • The most useful content for preparing for CBSE board exams.

    NCERT Solutions for Class 11 Biology: A Comprehensive Analysis

    Chemistry NCERT Solutions for Class 11 are more valuable than any other source of information. There are extensive explanations, complete solutions, descriptive illustrations, and more. Furthermore, we provide proper and current answers to all NCERT textbook exercise questions.

    With the help of digital files, students can study at their leisure.

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    How to Use NCERT Solutions for Class 11 Biology in Board and Competitive Exams?

    Biology is a discipline that teaches us everything there is to know about the natural world. It, like other scientific disciplines, uses observation, experimentation, and documentation to try to explain various phenomena, events, or species. Here are some helpful hints for studying biology.

    • Drawing

    The NCERT Class 11 Biology syllabus includes a lot of diagrams. However, you will not have much time during the exam to draw neatly or clearly, which may prohibit you from receiving the marks you require to pass the exam. As a result, practice some components of the essential schematics beforehand, such as shading and texturing. You will stand out among your classmates if you do this. Now, this may take some time to learn and master, but the payoff is well worth the effort.

    • Breaking down Information

    You may find it difficult to remember everything due to the sheer volume of data. That is why you should establish an information chunking strategy, in which the knowledge is broken down into small chunks to make it easier for the student to understand. This is particularly helpful since it reduces the cognitive burden, which in turn reduces mental tiredness. The way you divide the data is entirely up to you and your talents.

    • Making Note

    Although everyone is aware of this, not everyone puts it into practice. This strategy is underappreciated, although it is quite useful in examinations. Make a mental note of the key points that the teacher makes whenever you attend a lecture. This procedure stimulates your thoughts and makes it easier to recall knowledge. Additionally, this is an important tool to employ when revising for your exam. Because you prepared these notes, you will have an easier time understanding and remembering the information than if you used a textbook.

    NCERT Solutions, notes, question papers, and worksheets for subjects such as Mathematics, Physics, and Chemistry may be found here. We also have materials to help you prepare for competitive exams.

    Frequently Asked Questions on NCERT Solutions for Class 11 Biology

    What role does NCERT Class 11 Biology Solutions have in exam preparation?

    The questions in NCERT textbooks can be a great help in ensuring that you study properly and perform well in exams and assessments. Students can begin practicing NCERT Solutions Class 11 Biology right away, which will result in improved academic achievement in the future. As a result, a firm grasp of the syllabus would be developed.

    What is the finest biology book for Class 11?

    NCERT Biology Textbook is the most highly regarded book for the Class 11 test. The CBSE curriculum is rigorously followed in these books. It provides a solid foundation for preparation for board exams because it comprises question questions that are based on the CBSE syllabus for the subject.

    How can I get NCERT Biology Solutions for Class 11?

    To see the solutions, go to the Infinity Learn website and select NCERT Solutions, then select Class 11 and then subject. These solutions provided by us cover all these concepts, with detailed explanations.

    Do Infinity Learn NCERT Solutions for Class 11 Biology have better quality?

    NCERT Solutions for Class 11 Biology are created by highly experienced topic experts who have extensive experience in the field. They curate the solutions by strictly adhering to the latest CBSE board's syllabus and norms. The questions from the NCERT textbook are addressed comprehensively so that students may understand the ideas quickly.

    Does Infinity Learn NCERT Solutions for Class 11 Biology help students get full marks in their board exams?

    Yes, of course, NCERT Solutions for Class 11 Biology is one of the top study materials available on the internet. When students are unable to find a proper response to textbook questions, they can resort to subject-specific and chapter-specific solutions. It also enhances their capacity to respond to complex questions that may appear on board exams. Apart from the board student will also get help in board exams.


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