1. What is the milk of magnesia?
  2. Name two natural indicators?
  3. Is turmeric an indicator?
  4. Which gas is evolved when metal carbonates or metal hydrogen carbonate reacts with dilute acids?
  5. Is CO2 gas supporter of combustion?
  6. What happens when copper oxide reacts with conc. H2SO4?
  7. Which colour is obtained when CuO reacts with conc. HCl?
  8. What is the colour of pH paper in NaCl solution?
  9. Why does bleaching powder act as bleaching agent?
  10. Name the substance which on treatment with chlorine gives bleaching powder.
  11. Why does it act as disinfectant?
  12. Why is bread, biscuits fluffy?
  13. The acid present in atmosphere of Venus is …….
  14. Enamel is made up of……
  15. Toothpastes are……..in nature.
  16. Write the name and chemical formula of the products formed by heating gypsum at 373 k.                                                                   (AI 2010)
  17. Write the names and chemical formula of the products formed by the action of chlorine on slaked lime.                                                   (AI 2010)
  18. During summer season, a milkman usually adds very small amount of baking soda to fresh milk. Give one reason.                         (CBSE  2009)
  19. Name the gas usually liberated when a dilute acid reacts with a metal. What happens when a burning candle is brought near this gas?         (AI 2009C)
  20. Which gas is generally liberated when a dilute solution of hydrochloric acid reacts with an active metal?              (Foreign  2009)
  21. What is the color of litmus in a solution of ammonium hydroxide? (Foreign  2009)

Are you know about Transgenic plants for edible vaccines

Genes for peptide epitopes of pathogen can be used for the production of vaccines against a variety of human and animal diseases. This concept of vaccine production in transgenic plants was introduced in 1992. In the year 1995, biopharmaceutical company ProDigene from Texas (USA) conducted clinical trials, where pigs, fed with an edible maize vaccine, were found protected against the transmissible Gastroenteritis virus.

The company had also taken patent on this and other edible vaccine produced in transgenic crops. Such vaccines, whenever successful, will provide a technology for production and delivery of inexpensive vaccines, especially in the developing world. This technology will also be cheaper than expensive Recombinant cell culture based expression systems.

Are you know Scope and importance of Biotechnology

Biotechnology and Genomics, have their newest roots in the science of molecular biology and microbiology. Advances in these two areas have been exploited in a variety of ways both for production of industrially important biochemicals(including enzymes) and for basic studies in molecular biology.

Therefore, a new commercial environment has been created, in which many famous scientist including some Nobel Laureates opted to work for Biotechnology companies. Scores of these companies are created and closed down every year. In USA alone there are more than 300 such companies including Monsanto, Celera genomics, Biogen, DuPont, Novartis, etc.

जैव प्रौद्योगिकी और जीनोमिक्स, आणविक जीव विज्ञान और सूक्ष्म जीव विज्ञान के विज्ञान में अपनी नवीनतम जड़ें हैं। औद्योगिक रूप से महत्वपूर्ण जैव रासायनिक (एंजाइम सहित) के उत्पादन और आणविक जीव विज्ञान में बुनियादी अध्ययन दोनों के लिए इन दोनों क्षेत्रों में प्रगति का विभिन्न तरीकों से दोहन किया गया है।
इसलिए, एक नया व्यावसायिक वातावरण बनाया गया है, जिसमें कुछ नोबेल पुरस्कार विजेताओं सहित कई प्रसिद्ध वैज्ञानिकों ने जैव प्रौद्योगिकी कंपनियों के लिए काम करने का विकल्प चुना। इनमें से कई कंपनियां हर साल बनाई और बंद की जाती हैं। अकेले संयुक्त राज्य अमेरिका में मोनसेंटो, सेलेरा जीनोमिक्स, बायोजेन, ड्यूपॉन्ट, नोवार्टिस, आदि सहित 300 से अधिक ऐसी कंपनियां हैं।


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Microbes are both useful & harmful for human being. There no. of   m/o that cause diseases in human as well as plant & other animals.

Most importance bacteria are harmless to humans, and many bacteria are essential to the existence of plant and animal life. Only small fractions of bacteria cause disease; most bacteria attack organic matter only after it is dead.
Bacteria also enrich the soil in various ways. The so-called nitrogen fixing bacteria take nitrogen gas from the atmosphere and convert it to a form (nitrate) that green plants use for growth. Bacteria are important industrially in the production of cheese, yogurt, buttermilk, vinegar, and sauerkraut; in the preparations of antibiotic such as streptomycin, which is extracted from soil bacteria.

Biotechnology and bacteria

Biotechnology or Industrial microbiology is defined as the application of organisms such as bacteria, fungi and algae to the manufacturing and services industries. These include:

  • Fermentation processes, such as brewing, baking, cheese and butter manufacturing, Bacteria, often Lactobacillus in combination with yeasts and molds, have been used for thousands of years in the preparation of fermented foods such as cheese, pickles, soy sauce, sauerkraut, vinegar, wine, and yogurt.
  • Chemical manufacturing such as ethanol, acetone, organic acid, enzymes, perfumes etc. In the chemical industry, bacteria are most important in the production of enantiomerically pure chemicals for use as pharmaceuticals or agrochemicals.
  • Pharmaceuticals, such as antibiotics, vaccines and steroids.

Practical applications of embryo culture

It is considered to be a rapid method for multiplication of many plants as compared to micropropagation. Somatic embryogenesis can give rise to non-chemical mutant somatic embryos Can be made to develop from single cell. Virus free and non-pathogenic embryoids can develop from nucellus. This technique has been successfully employed in Citrus, as vegetative tissue is easily Affected by viruses clones produced from nucellus have been found to be virus Free.


  • For rapid clonal multiplication
  • For production of virus  free plant
  • Used for germplasm conservation
  • Used for producton of transgenic plants.

Apiculture: Rearing of honey been for increased production of honey and bee wax..

Emasculation: The removal of anthers or stamens from the flower of a parent Considered to be female in a cross.

Exotic breeds: Breeds introduced in an area from an outside country.

Germplasm collection: The entire collection (of plants/seeds) having all the Diverse alleles for all the genes in a given crop.

Heterosis: The superiority of F1, hybrids over either of the parents in terms of  Yield, growth. or any other function.

Livestock: Domesticated animals like cattle, sheep, goat, camels horse, pig etc.

Health and Disease (part – 1)

Health is a state of Complete physical, Mental and social well being. It define The perfect balance between environment and body.

Characteristics of Health

  1. Free from sickness & diseases.
  2. Free from unnecessary anxiety.
  3. Free from social and psychological tensions.
  4. Self Confidence
  5. Ability to work efficiently and at his best.

Factors Affecting Health

  1. Environmental factors.- light, Temp, natural disasters, soil ,type, rainfall etc
  2. Social Environmental factors.- job, condition, Housing condition family  atm. and relationship.
  3. Regular exercise & yoga.
  4. Balanced diet.
  5. Personal hygiene that includes self-cleanliness by developing clean habit.

Types of Diseases

  1. Congenital diseases

Tere are inborn diseases which are present from the birth.These are generally inheritable e.g.

i)Diseases caused by gene mutation Haemophilia, colour blindness etc.

ii)Diseases caused by #al mutation.

Down,s Syndrome, klinefelter,s syndrome etc.


Placenta is defined as temporary intimate mechanical and physiological connection b/w foetal and maternal tissues for the nutrition, respiration, and excretion etc. of foetus.

  • Surface of blastocyst gives rise to finger like outgrowth called chorionic villi, finally chorionic villi fuse with eroded uterine mucosa to form a true placenta. Placenta is fully formed in 10 weeks and lasts through out the pregnancy. Human placenta is haemochorial placenta in which all three maternal tissues of the placenta (uterine epithelium, endometrial mesenchymal connective tissue and endothelium of maternal blood capillaries) have been digested by trophoblast of chorionic placenta.
  • Human placenta is deciduate placenta because at the end of pregnancy some maternal tissue called deciduas is expelled.
  • Placenta help in nutrition.
  • Placenta help in respiration.
  • It also helps in excretion.
  • It act as endocrine gland, it secretes HCG and HPL, HCG help to maintain the corpus luteum for continuous secretion of progesterone to maintain the pregnancy at the end of gestation period, and it also produces the relaxin. Which helps in softening of pubic at time of child birth?
  • Antibodies against diphtheria, smallpox, measles etc. passes from maternal blood to foetal blood through placenta thus provide passive immunity.
  • It stores glycogen till the formation of liver.

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