NCERT Biology Class 12 Solutions

NCERT Solutions For Class 12 Biology

NCERT Biology Class 12 Solutions Chapter 1 Reproduction in Organisms

NCERT Solutions for Class 12 Biology where the understudies can undoubtedly set up every one of the ideas canvassed in the prospectus of class twelfth science in a much solid and successful way. Science NCERT Solutions class 12 is a valuable asset arranged by our exceedingly experienced employees to set up a solid theoretical base for the readiness of sheets just as aggressive tests. The points shrouded in class 12 prospectus conveys practically 50% of the weight in focused tests. Henceforth, we have ordered these class 12 Biology NCERT arrangements in a way that it plans understudies for sheets as well as for profoundly aggressive restorative tests like NEET. A few imperative ideas like Reproduction, Inheritance, Evolution, Food Production, Biotechnology, Ecosystem, biodiversity, and so forth are clarified decisively for the better comprehension of the two instructors and understudies. The ideas are instructed in a straightforward language remembering the current CBSE design also. We at comprehending the significance of concentrate material for compelling arrangements. Consequently, we have thought of these class 12 NCERT arrangements arranged selectiveness by our exceptionally qualified employees.

Chemistry Important Questions Class 11

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Reproduction is the biological process of giving birth to their individuals and this process varies from animals to animals. Few animals reproduce sexually, few through asexually and some lay eggs and some through budding and Binary Fission Reproduction in Organisms differ based on the presence and absence of the true nucleus. In all organisms, the complete process of reproduction takes place through the cell cycle – mitosis and meiosis. Like animals, the plant does reproduce and there are various modes of reproduction in plants

Chapter 2 Sexual Reproduction in Flowering Plants

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Microsporogenesis is defined as the process of formation of microspore from PMC. This process happens through meiosis. Pollen grains represent male gametophytes. The hard outer layer wall of the pollen grain is called exine and the inner wall is called inline. Matured pollen grain consists of generative cell and a vegetative cell. This was a brief on Sexual Reproduction in Flowering Plants.

NCERT Solutions For Class 12 Biology Chapter 3 Human Reproduction

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Reproduction is a biological process of producing its own offspring either by a sexual or an asexual process. In general, the human beings are born with two separate sexes – male and female and they reproduce or give birth to their young ones by a sexual mode of reproduction. Both male and female have a different set of reproductive organs in their respective systems and they play a very important role in the complete process of reproduction. In human reproduction, both parents participate in producing their offspring. The initial stage of reproduction in humans begins with the process of fertilization, Implantation, placenta formationfunctions of the placentadevelopment of the embryo followed with the baby’s birth and the lactation process.

NCERT Solutions For Class 12 Biology Chapter 4 Reproductive Health

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Chapter 4 specifically deals with the issue of sex education and reproductive health. It might be a sensitive topic but it is very important to create awareness about the subject. India has drastically changed in the last 50 years with regard to Reproductive health and sex education. It has changed for the better with lower mortality rates, cure, and prevention of most diseases.

NCERT Solutions For Class 12 Biology Chapter 5 Principles of Inheritance and Variation

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chapter 5 – principles of inheritance and variation is one of the key topics in 12th standard board examination. Class 12 chapter 5 solutions are provided here so that 12th standard students can learn the topic in a better way. The NCERT Solutions is one of the best tools to know the syllabus and the question pattern of class 12 biology examination. Not just biology, any NCERT Solution contains the best resources for the student to utilize in any exam.

NCERT Solutions For Class 12 Biology Chapter 6 Molecular Basis of Inheritance

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DNA is a double helix model with two types of nitrogenous base. They are purines and pyrimidines. The two types of purines are: Adenine and Guanine. The two types of pyrimidine are: cytosine and thymine. The hydrogen bond formed is between Adenine and thymine. Guanine is bonded with cytosine. The first genetic material was RNA. There are three types of RNA. They are: m – RNA, t – RNA, r – RNA. These three RNA’s are required for the synthesis of protein in the cell. m -RNA is also called messenger RNA. t- RNA is also called transfer RNA. and r – RNA is also called ribosomal RNA. This is a brief on Molecular Basis of Inheritance.

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NCERT Solutions For Class 12 Biology Chapter 7 Evolution

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The animals that we see now are the result of millions of years of evolution. This is brought about by organisms adapting to the changing environment or risk dying and becoming extinct. The earliest human ancestor didn’t even look remotely human – it was no larger than a millimeter and was the stepping stone in the evolution of fish and eventually, to humans.

Similarly, did you know that the whale’s earliest ancestor was completely terrestrial mammal – meaning that it lived on dry land and it slowly adapted to its aquatic environment over the course of millions of years – and it looked like a strange rendition of the modern day wolf. And bonus fact: Recent research has shown that hippos are the closest living relative to whales as they shared a common ancestor many million years ago.

NCERT Solutions For Class 12 Biology Chapter 8 Human Health and Diseases

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This chapter specifically deals with the  diseases and infections caused by various microbes. Humans are exposed to a whole multitude of microorganisms on the surface of their body, the air that we breathe and the water that we drink. However, most of these don’t pose a health hazard to us. Then, there are some microbes that cause life threatening and fatal diseases. These cause for these disease and their possible cures are analyzed below:

NCERT Solutions For Class 12 Biology Chapter 9 Strategies Enhancement in Food Production

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Animal husbandry:The difference between inbreeding and outbreeding is inbreeding means the breeding happens within the same breed whereas breeding happening between different breeds is called out breeding. When superior males of one breed are mated with superior females of another breed it is called cross breeding method. When a male and female from different related species are mated it is called interspecific hybridisation. This was a brief on Strategies Enhancement in Food Production.

NCERT Solutions For Class 12 Biology Chapter 10 Microbes in Human Welfare

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Microbes are also referred to as micro-organisms or microscopic organisms as they can only be seen under a microscope. They are tiny living creatures, invisible to the naked eye and are present  all around us, in air, water, soil and so on. They played a key role in the evolution of the planet earth. Few microbes cause severe infections and disease that even result in death and others are the beneficial ones and harmless to our lives. Disease-causing microbes are called as pathogens.  Influenza, tuberculosis, polio, cholera, HIV are some of the best examples of disease caused by these microbes.

The most common microbes include Bacteria, protozoa viroid, some algae, Fungi, and Viruses.

The application of Microbes in Human Welfare includes:

  1. As bio fertilizers.
  2. In sewage treatment.
  3. As a biocontrol agents.
  4. In the production of biogas.
  5. In Biochemical Oxygen Demand
  6. In the production of cheese, curd and yogurt.
  7. In the production of fermented food products like bread, beer and other Beverages.
  8. Useful in some industrial products such as ethanol fuel, antibiotics, vaccines, amino acids and in other pharmaceuticals products.

NCERT Solutions For Class 12 Biology Chapter 11 Biotechnology Principles and Processes

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Biotechnology is the branch of life science involved in the studying of living systems and involved in the production and development of different products to improve the quality of human life. There is a various application of Biotechnology in different fields such as in Pharmaceutical industries, food industries, agricultural industries, waste Management, sewage treatment plant, and also in different environment sectors.Among many techniques, the modern biotechnology is the result of the following two core techniques. They are-

  • Genetic engineering – It is the technique mainly used to change or to modify the genetic material (DNA/RNA), and to introduce them into other organisms.
  • Manufacturing of Antibiotics, Drugs and other Vaccines- It is an adequate maintenance of sterile conditions mainly used to support the growth and development of only the preferred group of microbes cells in great quantities for the production of biotechnological products like vaccines, antibiotics, enzymes, etc.

NCERT Solutions For Class 12 Biology Chapter 12 Biotechnology and its Application

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Biotechnology is mainly described as a technology which uses biology and other fields of life science to produce commercial products for human use by modifying or manipulating any biological system or living system for the improvement of products for various purposes.

Biotechnology and its applications include a broad spectrum including agriculture, medicines, genetically modified organisms, transgenic organisms, etc.

Biotechnology is an emerging field of research as it has the possibility to solve many biological related problems which could not be solved until now with conventional techniques. It has introduced a new trait into the crops for the production of new varieties of the crop which provides additional benefits to humans. For example – BT crops. These are the genetically engineered crops which reduce the use of pesticides and protects the crops from insects and other pests.

In the field of medicines, several techniques like recombinant DNA technology, stem cell therapy, and gene therapy are introduced to diagnosing several diseases. Many antibiotics and vaccinations have been discovered with the help of this technology to treat several dreadful diseases and other infections. Apart from all these, biotechnology has also focused of the several environmental issues like bioremediation for the removal of xenobiotic compounds from gases, solid and aqueous waste, development of bioplastics, and other safety measures to protect earth from pollution, global warming and greenhouse effect.

NCERT Solutions For Class 12 Biology Chapter 13 Organisms and Populations

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NCERT Solutions For Class 12 Biology Chapter 14 Ecosystem

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Ecology is the study of the interactions between the organism and its abiotic environment. It mainly deals with four levels of biological organization Organism, Populations, Communities and Biomes.

The environment in which we all are living is composed of both abiotic and biotic components. Water, light, Temperature, soil, are the key components of the environment. Biotic components comprise all the living organisms within an ecosystem and it includes plants, animals, birds, insects, bacteria, fungi and more. Abiotic components comprise all the non-living things in an ecosystem and it includes sunlight, temperature atmospheric gases water, and soil

Organisms and Populations are the levels of biological organization. The organism is mainly referred as a living entity which can function on its own and the sum of all the living organisms of the same species living together in a particular geographical area is termed as the population. The size or a growth of population is not static and it keeps on changing along with the time, depending upon the availability of food, predation pressure, temperature, weather and other climatic conditions.

NCERT Solutions For Class 12 Biology Chapter 15 Biodiversity and its Conservation

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The ecosystem is a biological community of all of the living things which includes plants, animals, birds and other living organisms interacting with each other and with their nonliving components in a particular region. The non-living components include atmosphere, earth, climate, sun, soil, and the weather. Overall, the ecosystem relates all the organisms to live in close proximity and to interact with each other. It is the network of interactions between and among the organisms, and their environment. Ecosystems consist of creatures that mutually benefit from each other.

For instance: Foxes and rabbits. These two species are in a relationship, where the rabbit eat plants and fox feeds the rabbit in order to survive.

By this way, the ecosystem balances the environment and has a knock on effect with the other creatures and plants living in the same regions. i.e. If the foxes hunt and feed on more rabbits, and plants may start to grow vigorously because there were the smaller number of rabbits to eat them.

NCERT Solutions For Class 12 Biology Chapter 16 Environmental Issues

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The class 12 Biology Chapter 15  solution includes the topic – Biodiversity: Genetic diversity, Species diversity, Ecological diversity. Species in India and Earth. Patterns of biodiversity: Latitudinal gradients, Species area relationships. Importance of species diversity to the ecosystem. Loss of biodiversity, Causes of loss of biodiversity: Habitat loss and fragmentation, Over exploitation, Alien species invasions, Co- extinctions. Biodiversity conservation: narrowly utilitarian, broadly utilitarian, In situ conservation, Ex situ conservation. The Biodiversity and its Conservation PDF is provided here for better understanding and clarification of the chapter.

When a single species shows high diversity at genetic level it is called as genetic diversity. When the diversity is at species level it is called as species diversity. Ecosystem level diversity is called as ecological diversity. Global diversity is divided into: Plants, Vertebrates and invertebrates. This was a brief on Biodiversity and its Conservation.

Over a past few decades, the environment has been facing a lot of environmental concerns and is increasing day by day. Global warming, acid rain, air pollution, water pollution, waste disposal, depletion of ozone layer, soil /land pollution, change in the climate are few environmental issues which are causing harm to humans, animals, plants and other living species on the planet earth. Humans play a significant role in environmental issues. The causes include poor industrial practices, cutting of trees- deforestation and lot of human practices which includes burning of fuels, emissions from vehicles, disposal of wastes into lakes and ponds, use of plastic goods, dumping of chemicals and other harmful products, washing, cleaning and misuse of clean and freshwater resources.

 

These Biology NCERT arrangements class 12 is included by the far-reaching well-ordered depiction utilizing appropriate clarifications, comprehended models, brief portrayal, and so forth of the considerable number of activities given in NCERT course books. Downloadable records of digital books, notes, pdf are additionally made accessible for understudies to kick-begin your test arrangements immediately. You can allude these section shrewd Biology class 12 NCERT arrangements from the reasonable connections referenced in the underneath table to exceed expectations in NEET just as board tests.

Key Benefits of Biology NCERT Solutions Class 12

Inquired about and composed by the accomplished and master educators

New Value Based Questions with arrangements in every section.

Offers top to bottom learning in simple language

Carefully pursues CBSE educational modules

Clears every major idea

One stop answer for CBSE board test Preparation

Tackled Exemplar issues for better practice

Point by point Analysis of NCERT Solutions Class 12 Biology

NCERT Textbooks are outstanding for their straightforwardness and clear portrayal of ideas. These course books are perfect for the understudies of class 12. It contains interest improved Questions for further lifting understudy’s learning limit. NCERT answers for class 12 science are set up in a straightforward way as per the schedule standards laid by CBSE making it simple for understudies to comprehend the subject.

The additional inquiries gave toward the finish of every part helps in the intensive comprehension of ideas. These Biology NCERT Solutions class 12 highlight all the fundamental data with essential ideas to help the understudies in the readiness of restorative selection tests like NEET. Vital ideas of NCERT course reading like physiology and morphology are delightfully represented and should be given most extreme significance.

5 must study Topics covered in Bio NCERT Solutions class 12

  • Principles of Inheritance and Variations
  • Reproduction in organisms
  • Microbes in Human Welfare
  • Evolution
  • Biotechnology

Class 12 Biology Practice Questions

Q1. What is the asexual reproductive structure in Sponge?

Q2. State true or false: Independent assortment can be seen in monohybrid cross.

Q3. Write one difference each between Oestrus cycle and Menstrual cycle

Q4. Elaborate the following:

  1. Apomixis
  2. Scutellum

Q5. How are microspores in angiosperms developed?

Q6. Which are the hormones produced by women during pregnancy?

Q7. Write one difference between codominance and incomplete dominance.

Q8. Who rediscovered Mendel’s laws?

Q9. YyRr is crossed with wrinkled pea plant. Explain the result with the diagram.

Q10. Define mutagen and give one example.

Q11. Define MTP.

Q12. What is menarche?

Q13. Draw labeled diagram of the seminiferous tubule.

Q14. Which part of the fallopian tube is closest to the ovary?

Q15. Draw anatropous ovule and label any 6 parts.

Q16. What happens to Synergids after fertilization?

Q17. What is the major difference between autogamy, xenogamy, and geitonogamy?

Q18. What are the gamete mother cells called in diploid organisms?

Q19. Explain the process of cross-pollination in plants.

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