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This section includes InterviewSolutions, each offering curated multiple-choice questions to sharpen your knowledge and support exam preparation. Choose a topic below to get started.
| 35951. |
Q-Define pollination. How does suitable pollination lead to fertilization? |
| Answer» Transfer of pollen grains from anther of a stamen to stigma of a carpel is called pollination | |
| 35952. |
Q-What is contraception? List four advantages of adopting contraceptive measures. |
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Answer» 1) it help to control population. 2)it protect us from sexually transmitted diseases 3)it help in family planning. 4) The prevention of pregnancy in women (by preventing fertilisation) is called contraception |
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| 35953. |
What is the biological importance of PH |
| Answer» \tImportance of pH in Everyday life:pH change and survival of animals - \tOur body works well within a narrow pH range of 7.0 to 7.8.\tWhen the pH of rain water is less than 5.6, it is known as acid rain.\tWhen this acid rain flows into rivers, it lowers the pH of the river water making the survival of aquatic life difficult.pH in our digestive system\tOur stomach produces hydrochloric acid which helps in the digestion of food without harming the stomach.\tSometimes excess acid is produced in the stomach which causes indigestion.\tTo get rid of this pain, bases called antacids are used.\tAntacids are a group of mild bases which react with the excess acid and neutralise it.\tCommonly used antacids are magnesium hydroxide [Mg(OH)2] and sodium bicarbonate[NaHCO3]\xa0pH change - Cause of tooth decay:Tooth decay starts when the pH in the mouth falls below 5.5. Tooth enamel is made up of calcium phosphate which is the hardest substance in the body. It is insoluble in water but gets corroded when the pH in the mouth falls below 5.5. The bacteria present in the mouth produce acids due to the degradation of sugar and food particles after eating. Hence, to prevent tooth decay, the mouth should be rinsed after eating food and toothpastes which are basic should be used for cleaning teeth to neutralise the excess acid. | |
| 35954. |
All the best for exam. Sab top karna |
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Answer» ????? Neeche se pkka karenge?? Same to you bro kosish yhi h top krne ke |
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| 35955. |
What is efflorescence ? |
| Answer» Efflorescence is the\xa0spontaneous loss of water by a hydrated salt, which occurs when the aqueous vapor pressure of the hydrate is greater than the partial pressure of the water vapour in the air. | |
| 35956. |
how about the image formed by spherical mirror |
| Answer» Image formation by Spherical Mirrors:The nature, position and size of the image formed by a concave mirror depends on the position of the object in relation to points P, F and C. The image formed is real for some positions of the object. It is found to be a virtual image for a certain other position. The image is either magnified, reduced or has the same size, depending on the position of the object. | |
| 35957. |
Which stakeholder cause maximum damage to forest |
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Answer» And except tribal people..... All human beings except animals ???? Industrialist . Industrialists and tribal people The industrialist I think industrialist ? ? Human being living near the forest. |
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| 35958. |
Why tooth decay begin when the pH is less than 5.5 ? |
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Answer» Because when pH is less than 5.5 than it means that there is Excess acid level in our mouth and because of Excess acid our teeths starts decaying Blood |
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| 35959. |
What is eflorance |
| Answer» Efflorescence is a crystalline deposit of salts that can form when water is present in or on brick, concrete, stone, stucco or other building surfaces | |
| 35960. |
How synapse act as one way valves ? |
| Answer» Synapses act like one way valves because the neurotransmitter is present only on one side of the gap. Due to this reason, the nerve impulses through a particular set of neurons can go across only from one side. | |
| 35961. |
Difference between soap and deterrent |
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Answer» Soap is a sodium and potassium salt of long carboxylic acidWhere is detergent is illuminate and sulphonate salt of long carboxylic acidSoap is effective in soft water onlyDetergent is effective in both soft water and hard water And detergent is used for removing the hardness of water and soap cannot do this soap is biodegradable detergent is notsoap cannt act in hard water as it forms scum while detergent can |
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| 35962. |
Are activities given in ncert important of science ?? |
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Answer» Yes, anyone of them can came in exam Yes,not be doubted yes why not Yes, some have came in exam also Yes Yesss, spcly in chem... |
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| 35963. |
What is the function of copper t |
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Answer» Copper t is safely placed in uterus and does not let ovary to reach egg to sperms copper T acts as a barrier as it creates a hostile environment for male gamete n kill it Copper t stops the growth of embroy by destroying it |
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| 35964. |
Transportation is a necessary evil.Jusyify. |
| Answer» Transpiration is a necessary evil As allows plant to release off excess of water | |
| 35965. |
describe the process of electrolytic refining of copper? |
| Answer» Electrolytic refining is a process of purification of metals which are highly reactive in nature . For example: sodium , magnesium, aluminum etc. So basically in this process,1.The impue metal is made the anode and the pure metal is made the cathode. 2. A solution of metal salt is used as electrolyte (in aqueous form) in which small amount of acid is mixed3. On passing the current the pure metal from the anode dissolves in the electrolyte and gets deposited on cathode (because metals are electopositive as they form +ve ions so the attracts the -ve electrode and depositd on it)4.The impurities go into the solution and settle down at the bottom of anode and are called anode mud.I hope you understood all this process Thanks | |
| 35966. |
How will yoy create an artificial aquatic ecosystem which is self sustainable? |
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Answer» aquarium not pond or lake because the latter are natural ecosystems Like aquarium, pond, lake etc |
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| 35967. |
Calcium does not occur in free state in nature.give reason. |
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Answer» Calcium is very reactive in nature and hence it is not found in free state in nature high reactivity It is highly reactive metal.thus, it react with its surrounding environment and form a compound. |
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| 35968. |
Induced current |
| Answer» Current which is made to pass through a electric circuit | |
| 35969. |
The angle of reflection is equal to the angle of incidence |
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Answer» Just angle of reflection is equal to angle of incidence it is known as law of reflection True. Always |
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| 35970. |
Function of thyroxine in our body |
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Answer» It control the feelings of human body Hi aadya Yes It regulates the rate of metabolism carbohydrates, fats and proteins in body.. |
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| 35971. |
Which is the less reactive non metal |
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Answer» Gold or silver Bromine |
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| 35972. |
sponication reaction |
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Answer» Reaction in which ester react with sodium hydroxide to form sodium ethanoate and ethanol.. Reaction in which ester react with sodium hydroxide to form sodium salt and alcohol Soapnification reaction |
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| 35973. |
Why atomic number is considered more fundamental property than atomic mass ? |
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Answer» Beciz it solves the problem of isobars in the peiodic table ,assigns hydrogen correct position in mordern periodic table. \tAtomic number of an element is numerically equal to the number of electrons round the nucleus.\tThe number of electrons in turn is equal to the number of protons in the nucleus.\tAtomic number is a more fundamental property of an element than its atomic mass because when the elements are arranged in the increasing order of their atomic number, most of the defects of Mendeleev\'s classification get rectified. |
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| 35974. |
What is the difference between gene chromosome and DNA |
| Answer» GeneA gene is a section of DNA which is involved in carrying information for a particular trait. They are functional units of heredity and are made of DNA.Genes are responsible for the hereditary and this is the reason why we all have similar characteristics of both the parents like the pigmentation of the eye, hair color, etc. There are about 29 to 30 thousands of genes in every cell of the human body. The term gene was first coined in the year 1909 by a Danish botanist Wilhelm Johannsen.ChromosomesChromosomes are thread-like structures merged together and are made of proteins and a single molecule of deoxyribonucleic acid – DNA. They are mainly found inside the nucleus of both animal and plant cells. They are passed to offspring from their parents, over generations. The term chromosome is derived from the Ancient Greek word meaning coloured body. Every human cell contains 46 or 23 pairs ofchromosomes. These chromosomes play an important role in cell division process and ensure that DNA molecules are copied and distributed evenly. | |
| 35975. |
Write the reaction five metals with water and acid |
| Answer» \tReaction of Metals with Water: Metals react with water to produce metal oxides with the release of hydrogen gas. But all metals do not react with water.Metal + Water → Metal oxide + HydrogenMetal oxides that are soluble in water dissolve in it to further form metal hydroxide.Metal oxide + Water → Metal hydroxideMetals such as sodium and potassium react vigorously with cold water to lead to evolution of hydrogen, which immediately catches fire producing a large quantity of heat.2Na + 2H2O\xa0→ 2NaOH + H2 + Heat2K\xa0+ 2H2O\xa0→ 2KOH + H2 + HeatMetals such as aluminium, zinc and iron do not react with cold or hot water, but they react with steam to form metal oxides and hydrogen.2Al\xa0+ 3H2O\xa0→ Al2O3\xa0+ 3H2 + Heat3Fe + 4H2O\xa0→ Fe3O4\xa0+ 4H2 + Heat\tReactions of Metals with Acids: Metals react with acids to form salt and hydrogen gas. Metal + Dilute acid → Salt + HydrogenMetals react with dilute hydrochloric acid to give metal chloride and hydrogen gas. Example - Magnesium reacts violently with dilute hydrochloric acid to form magnesium chloride and hydrogen.Mg + 2HCl\xa0→ MgCl2+ H2\xa0Metals react with sulphuric acid to form metal sulphate and hydrogen gas.Fe + H2SO4 → FeSO4+ H2\xa0\xa0\xa0 | |
| 35976. |
What are brisk effervescences? |
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Answer» Brisk effervescence\xa0is defined as the rapid or vigorous evolution of a gas in a chemical reaction. For example, when hydrochloric acid is added to sodium bicarbonate, bubbles of carbon dioxide gas are formed vigorously. Ester |
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| 35977. |
Explain why, a freely suspended magnet always point in the north-south direction |
| Answer» Because the one nend point of maganet act as north pole and other act as south therefore north pole is point towards south and south towards norths | |
| 35978. |
Describe in brief the structure and the functions of the placenta in human beings |
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Answer» Role of placenta1. placenta act to provide oxygen and nutrition to embryo. 2. It remove wastage material; CO2 from baby\' s body .3.Placenta attach to the wall of uterus and baby\'s umbilical cord arises from it. Placenta is a special tissue connection between embryo and uterine wall. It acts as an endocrine gland.Role of placenta:\tIt possesses villi that increase the surface area for absorption of nutrients.\tFacilitates passage of nutrition and oxygen to embryo from mother through blood.\tWaste substances produced by embryo are removed through placenta into mother’s blood. |
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| 35979. |
Define the term:focal plane |
| Answer» The front and rear (or back) focal planes are defined as the planes, perpendicular to the optic axis, which pass through the front and rear focal points. An object an infinite distance away from the optical system forms an image at the rear focal plane. For objects a finite distance away, the image is formed at a different location, but rays that leave the object parallel to one another cross at the rear focal plane. | |
| 35980. |
Reproduction lead to DNA how |
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Answer» At the reproduction time DNA is copying through meosis DNA or Deoxyribonucleotide is the basis of genetic mechanism. Genes are the specific parts of chromosomes or Deoxyribo Nucleic Acid (DNA) segments which determine the hereditary characteristics.Importance of DNA copying in reproduction:\tDNA copying mechanism is extremely necessary for reproduction as copying of DNA helps in transfer of information or characters from parents to offspring.\tIt also generates variations during sexual reproduction. This variation leads to evolution.\tDNA copying is also necessary because DNA (Deoxyribonucleic acid) is the genetic material found in chromosomes, which are present in the nucleus of a cell.\tDNA determines the body design of an individual. It carries the genetic information and key for the production of every type of cell proteins, which control the function of living organisms.\tDNA copying also helps in proper survival of the organism by similar copying and variation during DNA copying leads to evolution. |
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| 35981. |
How do plant excretion their waste? |
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Answer» Excretion in plants occurs through various means -1. Excess water is removed through stomata by transpiration which is the process of removal or evaporation of water.2. Plants also get rid of oxygen, a by - product in the process of photosynthesis and carbon dioxide which is the by - product formed during respiration. The plants get rid of these by stomata present in their leaves.3. Some of the wastes stored in the leaves are removed by the detachment of the leaves itself from the tree.4. Waste are also stored in the cellular vacuoles which do not affect the functioning of cytoplasm because of its outer membrane known as tonoplast.5. Other waste products are stored in resins and gums, especially in old xylem which stops working thereby. With the help of leaves |
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| 35982. |
Give another compound use in place of lead nitrate to form yellow p.pt. |
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Answer» Hii? Hi Aadya ? Potassium Iodide.. Silver bromide |
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| 35983. |
Difference betwn resistance n resisivity...? |
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Answer» Gi diku Resistance is the ability to resist the flow of electrons resistance depend on three factors 1 length of wire 2 area of cross section 3 material of which the wire is made - this third factor is known as resistivityR=pL/A Hlw ?? Hlw? Hi Kyu kya hua Hm theek ni h sis.... Bhai m theek hu aap kese Ho? ? Hnji bhaiya ji .. Hii sis hru..kitne time baad ayi ho Hi anku bhaiya Hii sisters....and aseem bhai. Hi diku Aap aajkl baat kyu ni krte ho... Buddy? resistance is the physical property while resistivity is the ability to resist the flow of current ..... ulta v ho skta hai sorry ?. ? Koi ni h kya |
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| 35984. |
Describe fission of amoeba |
| Answer» Binary Fission: Seen in bacteria, protozoa like Amoeba, Paramecium. (In these first pseudopodia withdrawn (karyokinesis) the nucleus of the parent cell divides and then the cytoplasm divides (cytokinesis) resulting in the formation of two daughter cells). It occurs during highly favourable conditions. The cell division can occur in any plane as in case of Amoeba. However, organisms like Leishmania. (cause Kala-azar), which have a whip like flagella at one end, binary fission occurs in a definite orientation in relation to the flagellum. | |
| 35985. |
Write important function of Testosterone |
| Answer» It develops secondary sexual characters in males. | |
| 35986. |
How can i learn full science in 4 days.please help me |
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Answer» You first relax and enjoy after watch video of science Read from short notes or ncert , solve sample papers of 2020 and study ncert questions . Go through ncert....and learn all main topics nd solve past yr questions. |
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| 35987. |
What is synthetic indicator |
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Answer» Artificial indicators A synthetic indicator is a mam made chemical substances used to determine pH.???? Simply....a man made indicator. A natural indicator is a natural substance that can be used to determine the pH of another substance.?? Indicator prepared from artificial substances and by humans is referred as synthetic indicator. Examples:- Phenolphthalein, litmus paper etc. |
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| 35988. |
A b battery light a bulb describe the energy change involved in the process |
| Answer» Electrical energy to heat energy to light energy | |
| 35989. |
Is it important to solve sample paper with the setting of 3 hrs ? |
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Answer» Yes it will increase your confidence and you come to know that where you are taking time to solve particular questions Yah it it very impt |
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| 35990. |
What is feedback mechanism ? |
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Answer» The excess or lack of hormone in our body will be harmful to us so the timing n amount of hormone releasing in our body is controlled by feedback mechanism Using feedback mechanism an organism\'s body can check and regulate hormones secretion. |
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| 35991. |
What is double fertilisation in flower . According ti three marks question |
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Answer» When pollen grain falls on stigma of a flower the pollen tube is generated through a germ pore. Pollen grains undergo 2 mitotic division . First division led to the formation of generative and vegetativ cell . Generative cell undergo mitosis to form 2 male gamates . One male gamate fuses with egg to form zygote and another male gamete fuses with secondary nuclues which is formed by fusion of 2 polar nuclei to form endosperm.This fertilisation is called double fertilisation. Any other answer please When one of the two male germ cell fuses with the centrally located polar nuclei after normal fertilisation |
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| 35992. |
Which plant help in ripening of fruit ? |
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Answer» Ethylene ncert me h ? Yes ethylene Plant hormone * ethylene |
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| 35993. |
A small size image image of 2 cm can be obtained by ???? |
| Answer» plane mirror | |
| 35994. |
What is a metal which react with air and form green colour subsatance |
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Answer» Its copper You are right ✔ I think copper and the green colour substance is copper carbonate |
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| 35995. |
Alltrope of carbon having fused benzene rings |
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Answer» Okay?? Graphite. I m not sure.. Graphite? |
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| 35996. |
What is nutrilization reaction |
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Answer» The reaction in which an acid reacts with a base to form salt and water is called as neutralisation reaction Acid+base=Salt+water. Acid+base=salt {neutralization rxn} Reaction between an acid n base is called neutralisation reaction. |
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| 35997. |
Name two biologically important compounds that contain both oxygen and nitogen ?? |
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Answer» The biologically important compounds that contain both oxygen and nitrogen are nitrates (NO2-) and nitrates (NO3-). These are important forms of nitrogen to be utilized by the plants to synthesize biomolecules like proteins. Urea and NO2 Nitrogen oxide |
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| 35998. |
Define the double circulation of the blood. Why is it necessary |
| Answer» The heart receives deoxygenated blood from different parts of the body, and it pumps this blood to the lungs. The oxygenated blood from the lungs returns to the heart, which is pumped again into different parts of the body by the heart. Thus, the blood passes twice through the heart making one complete round through the body. This is called double circulation.\xa0Pulmonary and systemic circulationThe pulmonary circulation pertains to lungs. The blood flows from the right ventricle to the lungs. Pulmonary veins collect oxygenated blood from the lungs and carry it back to the heart (left auricle).\xa0The systemic circulation pertains to the major circulation of the body. The aorta receives the blood from the left ventricle and sends it to the various parts of the body. Veins collect the deoxygenated blood from the body parts and pour it back into the right auricle. | |
| 35999. |
What is the ultimate source of energy for bio-mass, wind and ocean thermal energy...???? |
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Answer» sunlight 1-Plants; Bio mass is a type of material that is derived from plants. This plant derived material can be used to create fuels, such as ethanol and bio diesel, which are essentially carbon neutral.Wind; Wind energy can be used to produce electricity. As wind passes through the blades of a windmill, the blades spin. The shaft that is attached to the blades turns and powers a pump or turns a generator to produce electricity.Oceans; Oceans contain both thermal energy from the sun’s heat and mechanical energy from the tides and waves.Geothermal energy uses heat from within the earth to produce electricity and provide heating and cooling. Geothermal energy is an underused resource that emits little to no greenhouse gas emissions. Sun |
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| 36000. |
Which of the following is not mineral acid a) KOH (b)C2H5OH (C)NH4OH |
| Answer» No one is mineral acid | |