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InterviewSolution
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.
| 701. |
A charge `+Q`, is uniformaly distributed within a sphere of radius R. Find the electric field, due to this charge distribution, at a point distant r form the centre of the spehre where : (i) ` 0 lt r lt R` and `(ii) r gt R` |
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Answer» (i) `O lt r lt R`, (ii) Charge per unit volume ` rho= (Q)/((4)/(3)piR^3)` When point P is inside `(o lt r R)` then, charge enclosed by sphere of radius r will be `(4)/(3)pi R^2xx rho`. `=(4)/(3) pir^3xx (Q)/((4)/(3)piR^2)=(Qr^3)/(R^3)` So, electric field will be `E=(1)/(4pi epsilon_0) ((Qr^3)/(R^3))/(r^2)` ` E=(1)/(4pi epsilon_0) (Q)/(R^3).r` `rArr E prop r` (ii) When `r gt R`, Charge enclosed will be Q. So, `E=(1)/(4piepsilon_0) (Q)/(R^2)`. |
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| 702. |
The kinetic energy (K.E.) of a beam of electrons, accelerated through a potential V, equalws the energy of a photon of wavelength of 5460 nm. Find the de-Broglie wavelength associated with this beam of electrons. |
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Answer» `E=hv=(hc)/(lambda)=e` `V=(hc)/(lambda e) =(6.6xx 10^-34xx 3xx10^8)/(5460xx 10^-9-1.6xx10 ^-19)=0.22V` Using , ` lambda =(12.3)/(sqrt(V))A^@rArr lambda=(12.3)/(sqrt(0.22)) =26.2Å`. |
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| 703. |
Write the function of each of the following : (a) Middle piece in human sperm. (b) Tapeturn in anthers. (c) Luteinizing hormone in human males. |
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Answer» (a) Provides energy for movement. (b) Provides nourishment to developing pollen. (c) Stimulate synthesis and secretion of androgens or male hormones. |
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| 704. |
(a) India has greater ecosystem diversity than norway .Do you agree with the statement? Given reasons in support of your answer (b) Write the difference between genetic biodiversigy and species biodiversity that exists at all the levels of biologicval orgainisation |
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Answer» (a) India has greater ecosystem diversity than norway yes because of desert rain forest mangroves coral reefs wetlands estureaies and alphine meadows (b) Genetic diversity: (i)Genetic diversity is the total number of genetic characteristics in the genetic make up of a speicis (ii) A single speices musght show high diversity at the genitc level (e.g chinese indian american african) etc india has more than 50000 genetically different strains of rice and 1000 varities of mango. (iii) Genetic diversity allows species to adopt to changing environments .This diversity aims to ensure that some species survive drastic changes and thus carry on disirable genes. specific diversity : (i) It is the ratio of one species population over total number of organisms across all species in the givben biome zero would be infinete diversity and one represents only one speices present (ii) Species diversity is a measure of the diversity within an ecological community that incorporated both species richness (the number of speices in a community ) and the evenesss of speices (iii) For example the western Ghats have a greater amplhibian speices diversity than the eastern ghats .there are more than 200000 species in india of which several are confined to indian (endemic) |
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| 705. |
Explain the effect on the characteristics of a river when urban sewage is discharged in to it. |
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Answer» Effect of discharge in river : (i) Biodegradable organic matter: Lots of oxygen of wate is used by the icro organisms in decomposition of organic compounds which cause hsarp decline in dissolved oxygen and causes increased fish mortality and disturbances of aquatic food chains. (ii) Inorganic nutrients e.g nitrates and phosphates: cause rapid growth of algal forms and other aquatic plants in the water body called culteural or accelerated eutrophication .excessive growth of the palnktonic algae is called algal blooming (iii) pathogenci mirco organisms : These in trun decrease the quality of water increased death pf aquatic organisms or may be toxic for human being .consumption of such contaminated water my cause infection disease like cholera typhoid jaundice dysentery etc. |
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| 706. |
It is commonly observed that parents fell embarrassed to discuss freely with their adolescent children about sexuality and reproduction . The result of this parental inhibition is that the children go astray sometimes. (a) Explain the reasons that you fell behind such embarrassment amongst some parents to freely discuss such issues with their growing children. (b) By taking one example of a local plant and animals ,how would you help these parents to overcome such inhibitions about reproduction and sexuality ? |
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Answer» The reasons behind embarrassment amongst parents is due to improper communication and will of understanding between parents as well as children . Parents feel unable to communicate and explan important information to children and feel that the age gap is crucial reason for effctive communication. (b) The parents can take an example of the common plant china rose to explain the process of sexual reproduction . they can also employ various books , ariticles and stories to give the necessary information to the children . Example of brids can also be given but it is important that parents communicate effectively with their children about these matters. |
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| 707. |
In Snapdragon, a cross between true-breeding red flowered (RR) plants and true -breeding white flowered (rr) plants showed a progeny of plants with all pink flowers. (a) The appearance of pint flowers is not known as blending. Why ? (b) What is the phenomenon known as ? |
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Answer» (a) The appearance of pink flowers in `F_(1)` generation is not called blending because both red and white flowers appear in `F_(2)` generation on selfing. (b) This phenomenon is called incomplete dominance. |
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| 708. |
Differentiate between divergent and convergent evolution. Give one example of each. |
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Answer» Divergent evolution : 1. Here anatomically similar structures perform different functions. 2. Example : Forelimbs of cheetah and humans. 3. Such structure called Homologous. Convergent evolution 1. Here anatomically different structures perform similar functions 2. Example: Flippers of penguins and dolphins 3. Such structures are called analogous. |
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| 709. |
(a) Differentiate between exons and introns. (b) What is a plasmid? Why is it selected as vector? |
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Answer» Exons : The coding sequences or expressed sequences are defined as exons, Exons are said to be those sequence that appear in mature or processeds RNA. lntrons : The: exons are interrupted by introns. Introns or intervening sequences and do not appear in mature or processed RNA. (b) The construction of the first recombinant DNA emerged from the possibility oflinking a gene encoding antibiotic resistance with a native plasmid. The cutting of DNA at specific locations became possible with the discovery of the so-called molecular scissors-restriction enzymes. The cut piece of DNA was then linked with the plasmid DNA. These plasmid DNA act as vectors to transfer the piece of DNA attached to it. Mosquito acts as an insect vector to transfer the malarial parasite into human body. In the same way, a plasmid can be used as a vector to deliver an alien piece of DNA into the host organism. |
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| 710. |
What is ecological succession? Where and why would the rate of succession be faster in newly created pond or a forest destroyed by a forest fire ? |
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Answer» Ecological Succession : The sequential gradual and predictable· changes in the species composition in an area are called succession or ecological succession. The entire sequence of communities that successively changes in a given area is called sere(s). The species that invade a bare area are called pioneer species. Type of Ecological succession : 1. Hydrarch succession : The plant succession which takes place in wet area or water, leading to a successional series progress from hydric to the mesic conditions. 2. Xerarch succession: The plant succession which takes place in dry area, leading to a successional series from xeric to mesic conditions. The rate of succession will be faster in a forest destroyed by fire because here some soil or sediment is present leading to secondary succession while in a newly created pond the succession is primary, therefore, it is slow. |
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| 711. |
Explain the events in a normal woman during her menstrual cycle on the following days : (a) Pituitary hormone levels from 8 to 12 days. (b) Uterine events from 13 to 15 days. (c) Ovarian events from 16 to 23 days. |
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Answer» (a) Pituitary hormone levels from 8 to 12 days. It is the follicular‘phase where FSH stimulates the ovarian f licles to secretes estrogen, which in turn stimulates the prolifemtim of the endometrium of the uterine wall. The endometrial lining begins to thicken. (b) The uterine events between day 13 and 15 are governed by the high LH and FSH levels. The endometrium is intact under the effect of these hormones and also prepares itself forimpending pregnancy if it occurs. (c) Ovarian events frdm 16 to 23 days : Secretion of progesterone maintains the endometrium which is necessary for implantation of fertilized ovum and other events of pregnancy. |
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| 712. |
Peer pressure plays a negative role in triggering smoking habits in adolescents. As a school captain list any two activities you would like to organize with the help of senior students of your school and any other two activities you would like your school authorities to organize for the students to tackle this problem. Explain how theHe activities will help in doing so. |
| Answer» As a captain, we will organise craft competition to creat the awareness among the students. Secondly, we will prepare some student to delivers the debates during morning assembly to make it more effective and with the help of school authorities, we will prepare hoardings and put then up on walls. We will-also distribute some brouchers among the students including the lecture of principal during morning assembly, we can also arrange a play on any auspicious occasion. | |
| 713. |
Explain how and why controlled breeding experiment is carried out in cattle. |
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Answer» Controlled breeding experiments are carried out in cattle using artificial insenination. Herein, semen is collected from the male and injected into the reproductive tract of the selected female by the breeder. The semen can be used immediately or can be frozen and used at a later date. Controlled breedingexperiments are carried out in cattle for the following reasons : (i) To increase milk production by cattle. (ii) To increase growth rate in beef cattle. |
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| 714. |
(i) Why was a bacterium used in the first instance of the construction of an artificial recombinant DNA molecule ? (ii) Name the scientists who accomplished this and how ? |
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Answer» (i) A bacterium salmonella typhimurium was used in the first instance of construction of artificial recombinant DNA molecule because of the possibilities of linking agene encoding antibiotic resistance with a native plasmid of the bacterium. This was future made possible by the availability of restriction enzymes and the enzyme DNA ligase. (ii) Stanley Cohen and Herbert Boyer accomplished this in 1972 by isolating the antibiotic resistance gene by cutting out a piece of DNA from a plasmid which was responsible for conferring antibiotic resistance. The cutting of DNA at specific sites was possible with the availability of restriction enzymes. The cut DNA was the linked with the plasmid DNA using the enzyme DNA ligase. The plasmid DNA acts as vector to transfer the piece of DNA attached to it. |
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| 715. |
Which orientation of an electric dipole in a uniform electric field would correspond to stable equilibrium ? |
| Answer» The dipole is in stable equilibrium when electric dipole is in the direction of electric field vector and is parallel `vec(P) ||vec(E)`. | |
| 716. |
Write the difference between the tender coconut water and the thick, white kernel of a mature coconut and their ploidy. |
| Answer» The tender coconut water represents the free nuclear endosperm while, the white kernel is the cellular endosperm. The water and kernel of the endosperm are both triploid. | |
| 717. |
How does a restriction nuclease function ? Explain. |
| Answer» See Q.26 (a), Set-I, Delhi Board 2010 | |
| 718. |
Metion the ploidy of the different types of cells present in the female gametophyte of an angiosperm. |
| Answer» There is a characteristic distribution of the cells within the embryo sac. Three cells are grouped together at the microplar end and constitute the egg apparatus. The egg apparatus, in turn, consists of two synergids and one egg cell. The synergids have special cellular thickenings at the micropylar tip called filiform appartus, which play an important role in guiding the pollen tubes into the synergid. These cells are the chalazal and are called the antipodals. The large central cells as mentioned earlier, has two polar nuclei. Thus, a typical angiosperm embryo sac, at maturity, though 8-nucleate is 7-celled. | |
| 719. |
As a biologists explain the technique to a dairy farmer for increasing the yield of herd size of cattle in a short time. |
| Answer» MOET : Multiple Ovulation Embryo Transfer Technology : In this method, a cow is administread hormones with FSH - like activity to induce follicular maturation and super ovulation to produce 6-8 eggs. The animal is either mated with an elite bull or artificially inseminated. The fertilized eggs at `8-32 Cells stages are recovered non-surgically and transferred to surrogate mothers. The genetic mother is available for another round of super ovulation. This technology has been demonstrated for cattle, sheep, rabbits, buffalo and mares etc. | |
| 720. |
Nematode-specific genes are introduced into the tobacco plant using Agrobacterium vectors to develop resistance in tobacco plants against nematodes. Explain the events that occur in tobacco plant to develop resistance |
| Answer» See Q.29 (or ).out side delhi, set-1 ,2008 | |
| 721. |
Name the cell from which the endosperm of coconut develops. Give the characteristic features of endosperm of coconut |
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Answer» The endosperm of coconut develops from the primary endosperm cell. Characteristic features of endosperm of coconut are: The water of coconut is free-nuclear endosperm made up of thousands of free nuclei. The surrounding white kernel of coconut is the cellular endosperm |
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| 722. |
(A) Name any two places where it is essential to intall electrostatic precipitators . Why is it reuired to do so ? (b) Mention one limitation of the electtostatic precipitor. |
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Answer» The two places where it is essential to install electrostatic precipitators are the following: 1. thermal power plants 2. Smelters it is required so to separate particulate and gaseous air pollutants from harmless gases such as nitrogen , oxygen etc. ( B) An electrostatic precipitor cannot remove particulate matter of size 2.5 micrometers or less in diameter(PM.2.5) these fine particle can cause respiratory symptoms , inflammationnn and irration of lungs and premature death. |
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| 723. |
Name the respective forms in which the malaria parasite gains entry into (i) Human body, and (i) SporozoitC:, (ii) Gametocytes Body of female Anopheles. |
| Answer» (i) Sporozoitc:, (ii) Gametocytes | |
| 724. |
How does Cu-T acts as an effective contraceptive for human females? |
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Answer» Cu-Tis an ideal contraceptive device for human females because: Cu.ions released suppress sperm motility and fertilising capacity of sperms. It increases phagocytosis of sperms within the uterus. |
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| 725. |
Name the hormnal composition of the oral contraceptive used by human females. Explain how does it acts as a contraceptive. |
| Answer» Oral contraceptive of female consists of either progestogens or progesterone-estrogen combrnaion. They are taken as pills that inhibit ovulation and implantation | |
| 726. |
(a) Explain menstrual cycl in human females (b) How can the scientific understanding of the menstrual cycle of human females help as a contraceptive measure ? |
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Answer» (a) (i) The reproductive cycle in the female primates (E.g monkey apes and human is called) menstural cycle . (ii) The Ist mentrual cycle begins at puberty and is called menarche ltrbgt (iii) In human females menstruation is repeated at an average interval about `28//29` days and the cycle of events strarting from one menstraution till the next one is menstrual cycle. The phase of menstural cycle are as follows : (i) Menstrual phase : It lasts for 3-5 days .Menstrual flow results due to breakdown of endometrial lining of hte uterus and its blood vessel which form liquid that come out thorhg vagina menstruation only occurs if the releaaed ovum is not feritslied (ii) Follicular phase: It lasts for 8-10 dyas during phase the primary follicles in the ovary grows to become f fully mature graffian folliclea and simultaneously the endometrium fof uterus regenerates through proliferation.The secreation of LH and FSH increses gradually (iii) Obulatory phse: It lasts for 1 day .Ther is release of ovum Luteal phase : It lasts for 13 dys .There is LH surge .These induces the remaining part of graffian if fertiliztion occurs endometriumstarts preparing for implant ation . In the absence of fertiliztion corpus luteunm degenerates (i) Rhythm method : period absitinenerce in whinc coulples avoid coitius form day 10-17 the menestural cylce .In this method ovultion is expected occur and chancesf of fertizlaiton are very high (ii) Pills used by females also depends on menstrual cycle .oral pills have to be taken dialy for a period of 21 days starting within the first five days menstural cycle oral pills inhibit ovulation and implanation and also modify the equality of cervical mucus to prevent / retard entry of sperms |
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| 727. |
How does replication of long DNA molecules occur ? Explain the process. |
| Answer» See Q.29, Set0I, Delhi Board-2014. | |
| 728. |
Arrange the terms given below in their orthir order of occurrence describing their ructure and function in the earloy development of the humn embryo: Implantation, cleavage, inner cell mass, trophoblastl, blastomeres, endometrium, morula, blastocyst, |
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Answer» 1. Cleavage. 2. Blastomeres. 3. Morula. 4. Blastocyst. 5. Trophoblast. 6. Inner cell mass 7. Endoetrium. ltbtgt 8. Implantation. |
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| 729. |
(a) Name the hormone that initiates spermatogenesis in humans. Describe the process of spermatogenesis in spermatogenesis in sequence mentioning the ploidy of the cells at each step. (b) Draw the diagram of a mature human sperm and label the parts that : (i) helps it reaching to the ovum . (ii) providing energy for it to reach the ovum. (iii) helping it to gain entry into the ovum. |
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Answer» (b) (i) Head (ii) Neck (iii) Middle piece (iv) Tail |
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| 730. |
Schematically represent and explain the events of spermatogenesis in humans. |
| Answer» See Q.29(or), Set-III., Delhi Board-2009. | |
| 731. |
Differential between a ray and a wavefront. |
| Answer» The locus of all the particles of the medium, which any instant are cibrating in the same phase,is called the wavefront and an arrow drawn normal to the wavefront and pointing in the direction of propagation of the disturbance is called a ray. | |
| 732. |
How do interferéns protect us? |
| Answer» Interferon protect us to resist the infection of viruses. They prevent the synthesis of a virus, proteins in infected cells and help block the virus from reproducing (replicating itself). This slows down the process of the infection and gives the immune system time to respond to the virus. | |
| 733. |
In a dihybrid cross, when would the proportion of parental gene combinations be much higher than non-parental types, as experimentally shown by Morgan and his group? |
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Answer» This is possible when the two genes in a dihybrid cross were located on the same chromosome. Morgan associated this with physical association of the two genes or linkage. Morgan hybridized yellow bodied white eyed females to brown bodied red-eyed males and noticed that F2 ratio deviated from the usual. 9:3:3:1 |
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| 734. |
Define the following term in relation to proteins : (i) Peptide bond (ii) Denaturation of proteins. |
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Answer» (i) Peptide bond : The carboxyl group of one amino acid and amino acid and amino group of another amino acid gets condensed with the elimination of water molecule. The resulting - CO -NH - Linkage is called a peptide bond. (ii) Denaturation of proteins : A process that changes the physical and biological properties of proteins without affecting the chemical composition of a protein. |
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| 735. |
Write the location and function of the sertoli cells in humans. |
| Answer» Sertoli cells are located in the germinal epithelium of seminiferous tubules. They provide nourishment for developing spermatozoa. | |
| 736. |
What is primitive cell ? |
| Answer» A primitive cell has particles ( atoms) at all the corners of the unit cell. | |
| 737. |
If light of wavelength 412.5 nm is incident on each of the metals given below, which one will show photoelectric emission and why? . |
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Answer» Metal will show photoelectric emission only when energy of incident photons is greater than work function of that metal. `E = 1240// 421.5 mm` ` E = 3eV` It is greater than Na and K , so only those two will exit photoelectrons. |
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| 738. |
In a potentiometer arrangement for determining the emf of cell, the balance point of the cell in open circuit is 350 cm. When a resistance of `9 Omega` is used in the external circuit of cell , the balance point shifts to 300 cm. Determine the internal resistance of the cell. |
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Answer» Given `l_(1) = 350` `l_(2) = 300` `R = 9Omega` ltbrlt The internal resistance can be be calculate as . ` r= (R(l_(1) - l_(2)))/(l_(2))` ` r= 9((350-300)/(300)) = (9xx50)/(300) = 1.5Omega` |
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| 739. |
Read the graph given above and correlate the uterine events that take place according to the hormonal levels on (i) 6 - 15 days (ii) 16 - 25 days (iii) 26 - 28 days (if the ovum is not fertilised ) (b) Specify the sources of the hormones mentioned in the graph. |
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Answer» (i) It is the follicular phase where the FHS stimulates the overian follicles to secrete estrogen which in ture stimulates the proliferation of the endometrium of the uterine wall . The endometrial lining begins to thicken. (ii) Secretion of progesterone maintains the endometrium which is neccessary for implantation of fertilised ovum and other events of pregnancy. (iii) When fertilisation does not take place, the endometrium, disintegrates, leading to menstruation making a new cycle. (iv) Oestrogen is secreted by the ovarian follicle and progesterone is secreted by the corpus luteum. |
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| 740. |
A factory drains its waste water into the nearly lake. It has caused algal bloom. (a) How was the algal bloom caused ? (b) What would be the consequences ? (c) Name the phenomenon that caused it . |
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Answer» (a) The algal bloom was caused due to the presence of large amounts of nutrients in the lake. (b) Deterioration of water quality. (i) Increased fish mortality rate. (ii) Some bloom forming algae are toxic to humen being and animals. (c) Accelerated Eutrophication |
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| 741. |
( a) Explain giving reasons why the tourists visiting Rohtang Pass or Mansarovar are advised to resume normal ‘active life’ only after a few days of reaching there. (b) It is impossible to find small animals in the polar regions. Give reasons. |
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Answer» (a) Initially the person suffers from altitude sickness/nausea, fatigue and heart palpitation because of low oxygen availability and low atmospheric pressure. Gradually the body increases RBC production, decreasing binding capacity of HB and increases the breathing rate to get acclimatised. (b) Small birds have larger surface area relative to their volume, 30 they lose heat much faster and have to spend more energy to generate body heat through matabolism. |
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| 742. |
How is 1-propoxyproapane synthesised from propan-1-ol ? Write mechanism of the reaction. |
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Answer» `underset("Propan-1-01")(CH_(3)CH_(2)CH_(2)OH)overset(P,Br_(2))to underset("Bromopropane")(CH_(3)CH_(2)CH_(2)Br)` `CH_(3)CH_(2)CH_(2)overset(NaOH)tounderset("Sodium propoxide")(CH_(3)CH_(2)CH_(2)ONa)` `CH_(3)CH_(2)CH_(2)Br+CH_(3)CH_(2)CH_(2) ONato underset("1-propoxy propane")(CH_(3)CH_(2)CH_(2)OCH_(2)CH_(2)CH_(3))` |
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| 743. |
State kohlraush law of independent migration ions. Why does the conductivity of a solution decrease with dilution? |
| Answer» Kohlrausch law of independent migration of ions: The molar conductivity of an electrolyte at infinite dilution is the sum of the individual contributions of the anion and cation of he electrolye `lambda_(m)(CH_(3)COOH)=lambdaCH_(3)COO^(-)+lamdba_(H)^(+)` | |
| 744. |
How will you distinguish between the following pairs of terms: (i) Tetrahedral and octahedral voids (ii) Crystal lattice and unit cell |
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Answer» (i)Tetrahedral voids: Surrounded by 4 speres which lie at the verticles of regular tetrahedron Octahedral void: surrounded by 6 speres and formmed by combination of 2 triangular voids of 1st and 2nt lager (ii) Crystal lattice : 3-Darrangement of particles in space unit cell : smallest unit of crystal lattice when repeated in different direction generates the entire lattice |
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| 745. |
State Kohlrausch law of independent migration of ions. Write an expression for the molar conductivity of acetic acid at infinite dilution according to Kohlrausch law. `{:((b),"Calculate",:,wedge^(@)m" for acetic acid."),(,"Given that",:,wedge^(@)m(HCl)=426 " S " "cm"^(2)mol^(-1)),(,,,wedge^(@) m(NaCl)=126 " S " cm^(2) mol^(-1)),(,,,wedge^(@) m(CH_(3)COONa)=91 " S " cm^(2)mol^(-1)):}` |
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Answer» (a) Kohlrausch law : It states that limiting molar conductivity of an eletrolyte can be reprsented as the individual contribution of the anion and cation of the electrolyte. `wedge^(@)m(CH_(3)COOH) =lambda_(H^(+))^(@)lambda_(CH_(3)COO^(-))^(@)` (b) `^_(m)^(@)(HCl)" "=lamda_(H^(+))^(@)+lamda_(Cl^(-))^(@)` `wedge^(@)._(m)(NACl)" "=lambda^(@)._(Na^(+)+ lambda^(@)._(Cl)-` `wedge^(@)._(m-)(CH_(3)COONa)" "= lambda^(@)CH_(3)COO^(-^(+))lambda^(@)._(Na^(+))` `wedge^(@)._(m)(CH_(3)COONa)" "lambda^(@)._(H^(+))+lambda^(@)._(Cl^-)+^(@)._(CH_(3)COO^(-))+lambda^(@)._(Na^(+))- lambda^(@)._(Cl^-)-lambda^(@)._(Na`^(+))` `" "=wedge^(@)._(m)(HCl)+wedge^(@)._(m)(CH_(3)COONa)- wedge^(@)._(m) Nacl` `" "=426+91-126` `" "=426+91-126`. |
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| 746. |
A hemophilic father can never pass the gene for hemophilia to his son. Explain. |
| Answer» Because this is x-linked gentic disorder and the father cannot pass haemophila through y-chromosomes, only carrier female can produce a haemophilic son. | |
| 747. |
If 8 individuals in a laboratory population of 80 fruit flies died in a week, then what would be the death rate for population for the said period ? |
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Answer» Fruits flies in laboratory= 80 No. of fruits flies in a weak = 8 Death rate=`("No of Individuals dead")/("Total No of individual")` Death rate = `8/80`=0.1 The death rate will be 0.1 individual per week. |
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| 748. |
Name and describe that technique that helps in separating the DNA fragments formed by the use of restriction endonuclease. |
| Answer» Gel Electrophoresis : DNA are negatively charged, forced to move towards anode when electric field is applies in agarose gel matrix and separated according to their size, showing seiving effect, smaller fragment moves faster and further than the large. | |
| 749. |
Why are analogous structure a result of convergent evolution ? |
| Answer» Analogous structures perform the same function depite different structures. This points to convergent evalution. Eg : wings of butterfly and bird. | |
| 750. |
Why The vegetative propagules in the following : (a) Agave (b) Bryophyllum |
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Answer» (a) Bulbil of Agave. (b) Leaf bud of Bryophyllum. |
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