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SOLAR ECLIPSE 2025

   Introduction to Solar Eclipses Solar eclipses are one of the most fascinating celestial events, capturing the curiosity of scientists, astronomers, and the general public alike. These occur when the Moon passes between the Earth and the Sun, either partially or completely obscuring the Sun's light. There are different types of solar eclipses: Total Solar Eclipse : The Moon completely covers the Sun. Partial Solar Eclipse : The Moon partially blocks the Sun, creating a crescent shape. Annular Solar Eclipse : The Moon covers the center of the Sun, leaving a ring-like appearance. Hybrid Solar Eclipse : A rare eclipse that transitions between total and annular phases. The Solar Eclipse of 2025 In 2025, two significant solar eclipses will occur: March 29, 2025 – A partial solar eclipse , visible in several parts of the world but not visible from India . September 21, 2025 – Another partial solar eclipse , with possible limited visibility in India. Key Details of the March 29, ...

SAMPLE PAPER BIOLOGY 2023

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SECTION - A 1. An infertile couple was advised to undergo In vitro fertilization by the doctor. Out of the options given below, select the correct stage for transfer to the fallopian tube for successful results? (a) Zygote only (b) Zygote or early embryo upto 8 blastomeres (c) Embryos with more than 8 blastomeres (d) Blastocyst Stage EXPLANATION:(b) Zygote or early embryo upto 8 blastomeres 2. Given below are four contraceptive methods and their modes of action. Select the  correct match: (a) a)–(i) b)–(ii) c)– (iii) d)–(iv) (b) a)–(ii) b)–(iii) c)–(iii) d) – (i) (c) a)–(iii) b)–(iv) c)–(ii) d)–(i) (d) a)–(iv) b)–(i) c)– (iii) d)–(ii) EXPLAINATION: (c) a) - iii, b) - iv, c) - ii, d) - i 3 Which of the following amino acid residues will constitute the histone core? (a) Lysine and Arginine  (b) Asparagine and Arginine (c) Glutamine and Lysine  (d) Asparagine and Glutamine EXPLANATION:(a) Lysine and Arginine 4 Evolutionary convergence is development of a (a) common set of fu...

biotechnology class 12 2023

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1.Male sterility is widely used in crops such as maize, sunflower for hybrid production. Male sterile plants are created by introducing a gene encoding- (a) Barnase protein (b) TA29 (c) Barstar protein (d) Coat protein EXPLANATION: (a) Barnase gene was first introduced to produce male sterility in 1990. it is effective fertility restoration system in barstar. it is genetic and heritable. 2. Bodybuilders prefer to drink buffalo milk to build muscle mass. Determine the reason for this? (a) Easier to digest (b) Lower fat content (c) Higher calcium and phosphorus content (d) Balanced calorie source EXPLANATION: (c) buffalo milk has high-fat content, higher calcium and phosphorus content 3. An industrially important secondary metabolite which is used as a red pigment in lipsticks and dye for silk is obtained from- (a) Datura stramonium (b) Lithospermum erythrorhizon (c) Digitalis lanata (d) Coptis japonica EXPLANATION: (b) Lithospermum erythrorhizon commonly known as purple groomwell, red ...

sample paper class 10 for 2023 (science)

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SECTION -A 1.  The change in colour of the moist litmus paper in the given set-up is due to i. presence of acid ii. presence of base iii. presence of H⁺(aq) in the solution iv. presence of Litmus which acts as an indicator (a) i and ii (b) Only ii (c) Only iii (d) Only iv. EXPLANATION: (option c) litmus changes its colour in the presence of acids and bases hence act as an indicator. in the figure shown, HCl is liberated during the reaction of  NaCl and conc H2SO4 which turns blue litmus red ( acid of the solution has H+ ions) 2. In the redox reaction  MnO2 + 4HCl → MnCl2 + 2H2O + Cl2 (a) MnO2 is reduced to MnCl2& HCl is oxidized to H2O (b) MnO2 is reduced to MnCl2& HCl is oxidized to Cl2 (c) MnO2 is oxidized to MnCl2 & HCl is reduced to Cl2 (d) MnO2 is oxidized to MnCl2 & HCl is reduced to H2O EXPLANATION: (b) it is an example of redox reaction in which a substance which loses oxygen or gain hydrogen is reduced and which gain oxygen and loses hydrogen...