MSBSHSE Class 9 Science Chapter 17 Introduction to Biotechnology Solutions

MSBSHSE Class 9 Science Chapter 17 Introduction to Biotechnology Solutions is a comprehensive reference material. It is very helpful from the standpoint of your MSBSHSE Class 9 Science examination. The solutions have detailed answers and step by step explanations are provided here. These will help students to understand the basic concepts of the chapter and ace the exams.

Introduction to Biotechnology, a crucial concept of Science is discussed in detail in this chapter. The topics covered are Tissues: animal tissues and plant tissues, Tissue culture, Agritourism, Agri-business and so on. Students can master the subject most proficiently by studying with the help of these MSBSHSE Class 9 Solutions of Science Chapter 17 Introduction to Biotechnology. These solutions are prepared efficiently by following proper research. These will help students to ace the exams, as they get more familiar with the exam questions. The well designed content is easy to comprehend and helps students to learn the subject. This solution covers the topics from Chapter 17, according to the latest MSBSHSE Syllabus for Class 9. The solutions to the questions listed here are designed to help students so that they do well academically. Hence, giving highly relevant answers helps students to answer exams more confidently.

Maharashtra Board Class 9 Science Chapter 17- Important Questions & Answers

1. Find the odd one out in Xylem, phloem, permanent tissue, meristematic tissue. Why?

Answer: Xylem and Phloem are a type of permanent tissue. So, the odd one out is the meristematic tissue.

2. Epithelium, Muscle fibre, nerve fibre, epidermis. Which is the odd one? Give reason.

Answer: Here, other than Epidermis all others are animal tissues even if of different kinds. Epidermis is the plant tissue, an outer layer of cells found in plants and so it is the odd one out.

3. Which is the odd one out from cartilage, bone, tendon, cardiac muscle? Why?

Answer: Cartilage, bone and tendon are all types of connective tissues, whereas cardiac muscle is a muscular tissue. Hence, the odd one out is the cardiac muscle.

4. Find the difference between the simple tissue and the complex tissue in plants.

Answer: Find below certain differences between the simple tissue and the complex tissue in plants:

5. Write short notes on meristematic tissue.

Answer: Found in specific parts of a plant, meristematic tissue helps in the development of those parts of the plant. Meanwhile, the cells of the meristematic tissue are of thick cytoplasm, a conspicuous nucleus and a thin cell well, all compactly packed together. These cells, though devoid of vacuoles, are highly active. Main function of the meristematic tissue is to help with the plant growth. Meanwhile, based on the location, meristematic tissues are of three kinds.

6. Write short notes on xylem.

Answer: A type of complex permanent tissue, xylem is a structure like an interconnected tube, that conducts water and minerals only in upward direction. It consists of thick walled dead cells. Tracheids, vessels and xylem fibres-dead cells, Xylem parenchyma-living cells are all types of cells.

7. Write short notes about striated muscles.

Answer: Striated muscles are a type of muscular tissue. Meanwhile, you can also find alternate dark and light bands on these muscles, called skeletal muscles, which are attached to bones. These cells move voluntarily and so are called voluntary muscles. The cells of these muscles are long, cylindrical, multinucleate and have no branches. These muscles are responsible for the movements of arms and legs, running, speaking and more.

8. Write a note on Agro-complementary business.

Answer: Animal husbandry, sericulture and poultry farming are all types of Agro-complementary business. Learn more about Animal husbandry-poultry farming and sericulture from the respective links.

9. Write notes on genetic engineering.

Answer: The process in which genes for a particular character are introduced inside the chromosome of the cell of an individual is known as genetic engineering. When the gene for a particular character is introduced in a plant cell then transgenic plants are produced. Genetic engineering is mainly applied to:

(i) Manufacture enzymes, proteins, vaccines and antibiotics using bioprocess technology

(ii) Develop crops that are pest-resistant and disease-resistant

(iii) Identify and correct genetic defects using gene therapy

(iv) Forensic application, in the identification of criminals using restriction fragment length polymorphism (RFLP)

10. Write about Sericulture.

Answer: Bombyx mori is the most commonly used variety of Sericulture Silkworm (moths) for the purpose of producing silk. Meanwhile, the life cycle of the silk moth constitutes four stages, namely egg, larva, pupa and adult. In an attempt to lessen the incubation period, thousands of eggs deposited by female moths are incubated artificially and the larvae hatching out of these eggs are released on mulberry plants. Larvae that are nourished by feeding on mulberry leaves, after about 3-4 days move to the branches of the mulberry plant. The silk thread is produced from the secretion of their salivary glands. Larvae forms a cocoon that is spherical in shape by spinning this thread around them. Now, ten days prior to puma transforming to an adult, all the cocoons are transferred into boiling water, due to which the pupa dies in the cocoon. From this, the silk fibres come loose. They are unwound, processed and reeled. Varieties of fabric are woven using these silk threads.

11. Explain the meaning of biotechnology and its impact on agricultural management, with suitable examples.

Answer: Biotechnology helps to produce plants and animals with some new characteristics, along with their natural ones. The techniques of bringing about enhancement in living organisms using artificial genetic changes and via hybridization for the welfare of human beings, are together known as ‘Biotechnology’. This includes the techniques of genetic engineering and tissue culture, which are applied for the manufacture of cash crops, improvement in varieties of cash crops, increase in abilities of plants to withstand environmental stresses, vaccine production, early diagnosis of congenital diseases, organ transplant, cancer research, production of artificial skin, cartilage, and so on in laboratories. Biotechnology also brings about certain changes to agricultural management. Learn them from Biotechnology in Agriculture.

12. Which are the two main techniques used in biotechnology?

Answer: The two main techniques used in biotechnology are genetic engineering and tissue culture.

13. Define the term tissue and explain the concept of tissue culture with illustration.

Answer: Tissue is a group of cells having the same origin, same structure and same function. Plants and animals have different types of tissue for performing the necessary functions. Meanwhile, tissue culture is a technique of biotechnology applied to make improvements in living organisms via artificial genetic modification and through hybridization. Have you seen flowers of the same variety but of 2 or 3 different colours borne by the same plant? This is done using the modern gardening technique, tissue culture. ‘Ex vivo growth of cells or tissues in an aseptic and nutrient-rich medium’ is termed tissue culture. It is possible to develop a complete organism from a single cell or from tissue by applying the tissue culture technique. During this technique, a liquid, solid gel-like medium made from agar is used. This gel like substance supplies nutrients and energy required for tissue culture.

14. Plants and animals have different types of tissue to perform the necessary functions. Why?

Answer: Since, plants are sedentary, a large variety of their tissues are of the type that give support. There are also dead cells in some of the tissues, which do not need much attention. Additionally, growth of the plants takes place only in certain parts of their body, where the tissues contain dividing cells. Alternatively, because animals have to move from one place to another in search of food, shelter and partners, they have greater energy needs. The tissues of animals are also made of living cells. Animals undergo uniform growth in all parts of their body and they do not have any different dividing and non-dividing tissue. Hence, the plants and animals have different types of tissue in order to perform the necessary functions.

15. What are the four main types of animal tissues?

Answer: Since, different tissues perform different functions in the organs. Animal tissues are, accordingly, classified into four main types. They are epithelial tissue, connective tissue, muscular tissue and nervous tissue.

16. What is the importance of blood?

Answer: A type of connective tissue, blood circulates from one part of our body to another and transports different materials. For example, it transports oxygen and nutrients to all cells in the body. Similarly, blood also helps to transport the waste materials produced all over the body to the kidney for excretion.

17. What is Epithelial tissue?

Answer: Epithelial tissue is the protective coverings in the animal body. Cells in this tissue are closely packed and form continuous layers. Any material that enters the body has to first encounter the epithelial tissue. There is a fibrous membrane in the epithelial tissue that separates the cells of the epithelial tissue from the cells of other underlying tissues. Epithelial tissues are used to make the skin, mucous layer of the mouth cavity, inner surface of blood vessels, walls of the alveoli and so on.

18. What are the types of epithelial tissues?

Answer: Squamous epithelium, Stratified epithelium, Columnar epithelium, Glandular epithelium, Ciliated epithelium, Cuboidal epithelium are all different types of epithelial tissues.

19. What is the function of the Squamous epithelium and Ciliated epithelium?

Answer: Found in the inner surface of the respiratory tract, the ciliated epithelium, helps to push mucus and air forward to keep the air passage free. Meanwhile, Squamous epithelium is located in the inner surface of the mouth, oesophagus, blood-vessels and alveoli, helping in selective transport of substances.

20. Describe columnar epithelium. What is its function?

Answer: Columnar epithelium are column-like tall cells with upper free surface bearing folds made of these cells at places of absorption. These are located in the inner surface (mucosa) of the intestine and alimentary canal. Columnar epithelium helps with the secretion of digestive juice, absorption of nutrients and so on.

21. What are tendons and ligaments?

Answer: They are types of connective tissues located at the joints. The tendons are fibrous, strong and less elastic, while ligaments are strong and highly flexible. Tendons connect the muscles to the bones and ligaments join two bones to each other.

22. Why do you experience the contraction and relaxation of muscles at every movement?

Answer: Muscle fibres and muscular tissues are made from a special type of contractile proteins, which causes the muscles to contract and relax. Muscular tissues are made of the long cells of muscle fibres. Muscular movement takes place as a result of contraction and relaxation of the contractile proteins in these cells.

23. Explain about non-striated muscles.

Answer: Muscle cells of non-striated muscles are short, spindle-shaped, uninucleate with no branches. These muscles do not have any dark and light bands and they are not connected to the bones. They undergo involuntary movements and so are termed as involuntary muscles. These muscles are found in the alimentary canal, blood vessels and so on. These muscles are used for functions such as movements of eyelids, passage of food via the alimentary canal, contraction and relaxation of blood vessels and so on.

24. Write a note on Nervous Tissue.

Answer: People respond to stimuli like touch, sound, odour, colour and more with the help of nervous tissue. Meanwhile, cells of the nervous tissue are especially manufactured to become excited and conduct that excitation from one part of the body to another. The cell body that contains the cytoplasm and the nucleus is the main part of every nerve cell. A large number of small, branched fibres called dendrites also arise from the cell body. One of the fibres, however, is extremely long even upto one meter and is called the axon. Several nerve cells are bound together using connective tissue to form a nerve. Nervous tissue is located in the brain, spinal cord and the network of nerves spread all through the body. In most animals, action in response to a stimulus takes place as a result of the integrated functioning of nervous tissue and muscular tissue.

25. What are the subtypes of parenchyma tissues?

Answer: The subtypes of parenchyma tissues are Chlorenchyma (e.g. leaves) that performs photosynthesis and Aerenchyma that helps aquatic plants, leaves and stem to float.

26. Explain the application of biotechnology in floriculture, nurseries and forestry.

Answer: Nurseries are used to grow gardens on a large scale for afforestation, reforestation and so on. Seedlings are required in large numbers for all these purposes. Hence, in such cases it is profitable to manufacture plantlets with the help of tissue culture techniques. In this way, as seeds of better quality crops are being generated, farmers globally are cultivating the GM crops on a large scale. The area under its cultivation is going up day by day. High Yielding Varieties of GM crops like banana, maize, rice, potato, soybean, tomato, cotton, apple, brinjal, papaya, beet, rose, tobacco, wheat, etc. are available. Pest-resistant genes have been introduced in some of these GM crops.

• Tissue culture is used to grow on large scale those plants that bear flowers, fruits of excellent quality.
• It is possible to get fully grown plants in shorter durations.
• Plants can be grown on a large scale even without pollination or if germinating seeds are not available. For example, orchids or pitcher plants do not germinate but can easily be generated using tissue culture.
• In a bioreactor, cells can be grown in a more nutritive medium and protected from pathogens. Bioreactors are useful for producing plantlets on a very large scale.
• Large numbers of seedlings/plantlets can be produced in a short time using minimum resources and materials.
• Usually, plants produced by tissue culture and genetic modification techniques are disease-free. Plantlets manufactured by tissue culture of the meristem are virus-free.
• Embryos formed by conventional hybridization techniques between two or more varieties may not grow fully for some reasons. However, embryos produced by tissue culture techniques always complete their growth.
• Rare and endangered plants can be grown and protected from extinction by applying tissue culture techniques. Similarly, various parts and seeds of such plants can be preserved by tissue culture and those varieties can be protected.

27. In India, what are the reasons for practising animal husbandry?

Answer: In India, animal husbandry is applied for producing milk and for using the cattle to help in farming operations. Example: Cows and buffaloes are reared for milk and bulls and male buffaloes for pulling the heavy loads.

Students can also refer to MSBSHSE Class 9 textbooks to prepare most competently for the exam. Other resources we offer are the syllabus and question papers. Stay tuned to get more details about the board and exams.