24277 + Interview Questions in Biology in Class 12 Page 405 InterviewSolution

20201.	Question : Bt cotton is regarded as an important achievement of genetic engineering. What does Bt stands for.
Answer» SOLUTION :BACILLUS thuringiensis

Discussion

20202.	Question : Bt cotton is not
Answer» a GM plant insect resistant a bacterial gene expressing system resistant to all pesticides Solution :Several transgenic PLANTS have been DEVELOPED. One such plane is BT cotton in which the Bt TOXIN has been used as a biological insecticide The bacterium-Bacillus thuringiensis is COMMON soil bacteria which produces a protein toxin that kills certain insects. Bt toxin gene was isolated from Bacillus thuringiensis and was incorporated into several crops plant such as cotton. Bt cotton is resistant to insect but is not pesticide resistant.

Discussion

20203.	Question :Bt cotton is not(A) a GM plant(B) Insect resistant(C) a bacterial gene expressing system(D) resistant to all pesticides
Answer» A GM plant Insect resistant A bacterial gene EXPRESSING SYSTEM Resistant to all pesticides Solution :BT cotton is a genetically modified plant, genome of it is modified by INSERTING a foreign gene from a soil bacterium Bacillus thurengenesis. This genetically modified plant cell produces .cry. protein. This protein when is ingested kill certain insects like, lepidopterancoleopterans and dipterans.

Discussion

20204.	Question : BT cotton is not :
Answer» A GM plant Insect resistant A BACTERIAL GENE EXPRESSION system Resistant to all pesticides Answer :D

Discussion

20205.	Question : Bt. cotton is a well known example of application of Biotechnology in agricul ture. Bt. cotton reduces the use of pesticides. Explain.
Answer» Solution :Bt cotton is a pest RESISTANT plant. Bt toxin gene has been cloned from Bacillus thuringienesis and been expressed in plants to provide resist ance to INSECTS WITHOUT the need for INSECTICIDES. So it REDUCES the use of pesticides.

Discussion

20206.	Question : Bt - cotton has genes to repel
Answer» BACTERIAL PATHOGENS Fungal pathogens Nematodes pathogens INSECT pathogens SOLUTION :Insect pathogens

Discussion

20207.	Question : Bt cotton is a disease resistant transgenic plants.
Answer» ANSWER :INSECT RESISTANT

Discussion

20208.	Question : Bt cotton genes repel
Answer» BACTERIAL pathogens Fungal pathogens Nematode parasites Insect pests Answer :D

Discussion

20209.	Question : Bt cotton has been produced by
Answer» In-situ HYBRIDISATION of Bt-gene Northern BLOTTING of Bt-gene Cloning of Bt-gene Southern blotting of Bt-gene Answer :C

Discussion

20210.	Question : 'Bt Cotton''
Answer» Bt COTTON is a GENETICALLY modified organism Bt toxins are insecticidel to the larvae of moths . Increase pollination by insects COST of Bt cotton seed is high SOLUTION :N/A

Discussion

20211.	Question : Bt corn been made resistant from corn borer disease by intoduction of the gene
Answer» CRYLAB cryllAb `amp^(R)` Trp Solution :CrylAb has been introduces in Bt CORN to protect it from corn BORER.

Discussion

20212.	Question : Bryophytes show an advancement over algae in :-
Answer» Having multicellular sporophytic GENERATION Having parasatic SPOROPHYTE Having ZYGOTIC meiosis None of the above Answer :A

Discussion

20213.	Question : Bryophytes have probably evolved from
Answer» BLUE GREEN algae Green algae Blue algae Red algae Answer :B

Discussion

20214.	Question : Bryophytes can be separated from algae because they
Answer» are thalloid forms have no conducting tissue possessarchegonia with outer layer of sterile cells contain chloroplasts in their cells Solution :(C) Archegonia is female sex ORGAN in bryophytes. It is a flask-shaped multicellular organ. It is composed of a CYLINDRICAL upper portion called neck with a single layer of sterile cells called Neck Canal Cells (NCC)and a lower swollen sac-like portion called VENTER. It also has layer or layers of sterile cells.Venter ENCLOSES a larger egg cell and a smaller (just above to egg)Venter Canal Cell (VCC).

Discussion

20215.	Question : Bryophytes comprise
Answer» SPOROPHYTE of longer duration dominant phase of sporophyte which is parasitic dominantphase of gametophyte which produces spores small sporophyte phase GENERALLY parasitic on gametophyte Solution :(d) Bryophyta is a group of thalloid, non-vascular, cryptogams which have gametophytic (haploid phase) as dominant phase. It BEARS diploid SPOROPHYTIC phase which takes food from gametophytic phase, thus behaves as parasite on gametophyte.

Discussion

20216.	Question : Bryophytes can be compared with amphibians since both are (i) Autotrophic (ii) Dependent on water for reproduction (iii) Without endoskeleton (iv) Devoid of impervious body surface (v) With separate sexes
Answer» II,iv i,ii,iv ii,III,iv i,iii,iv Answer :A

Discussion

20217.	Question : Bryophytes are not characterised by :
Answer» Rhizoids Meiosis in SPORE MOTHER cell Reduction DIVISION in zygote Dependent sporophyte Answer :C

Discussion

20218.	Question : Bryophytes are different than algae in
Answer» having MULTICELLULAR sporophytic GENERATION having no sporophyte having ZYGOTIC meiosis formation of EMBRYO ANSWER :D

Discussion

20219.	Question : Bryophytes are amphibians because
Answer» they require a layer of water for carrying out SEXUAL reproduction they OCCUR in damp places they are mostly aquatic All of the above Solution :(a) Bryophytes are CALLED amphibians (amphibians of plant kingdom). They are first amongst land plants which occur in damp and shady habitats. As vascular tisues are ABSENT, male gametes require a layer of water for SWIMMING and fertilisation.

Discussion

20220.	Question : Bryophytes and Pteridophytes produce a large number of male gametes but relatively vary few female gametes. Why ?
Answer» Solution :Because male gemete need medium (water) to REACH egg/FEMALE GAMETE. A large NUMBER of the male gametes fail to reach the female gamete. It increases the probability of FERTILISATION.

Discussion

20221.	Question : Bryophyta are not tall plants due to:-
Answer» Absence of meristern Absence of vascular tissues PRESENCE of ROOT system All the above ANSWER :B

Discussion

20222.	Question : Bryophyllum vegetatively multiples by adventitious buds where , water hyacinth by____
Answer»

Discussion

20223.	Question : Bryophyllum is the best example of propagation by...............
Answer» ANSWER :LEAF

Discussion

20224.	Question : Bryophyllum can be propagated vegetatively by:
Answer» Stem Root Leaf Flower Answer :C

Discussion

20225.	Question : Brush border epithelium occurs in
Answer» Trachea Stomach Small intestine Fallopian tube Answer :C

Discussion

20226.	Question : Brunner's glands occur in:
Answer» SUBMUCOSA of duodenum Submucosa of stomach Mucosa of oesophagius Mucosa ofileum Answer :A

Discussion

20227.	Question : Brunner's glands are found in submucosa of_____.
Answer» ANSWER :DUODENUM

Discussion

20228.	Question : Brown sugar is :
Answer» Barbiturate Herion LSD Hashish Answer :B

Discussion

20229.	Question : Brown rust of wheat is caused by ...........
Answer» USTILAGO NUDA tritici Puccinia recondita Puccinia striiformis Puccinia graminis tritici Answer :B

Discussion

20230.	Question : Brown algae is characterised by th presence of
Answer» phycocyanin phycoerythrin FUCOXANTHIN haematochrome Solution :(C) In addition to chlorophyll-a, brown algae posses special carotenoids and fucoxanthin.It is due to the fucoxanthin (brown pigment) that these algae APPEAR brown.Phycocyaninandphycoerythrin are phycobilins which are FOUND in red algae (phycocyanin-r,phycoerythrin-r)and blue-green algae (phycocyanin-c,phycoerythrin-c).

Discussion

20231.	Question : Brooders pneumonia disease is connected with
Answer» HONEY bee Hens Fish Pigs Answer :B

Discussion

20232.	Question : Broca's area is concerned with_____
Answer» ANSWER :SPEECH

Discussion

20233.	Question : Broad part of leaf is
Answer» LEAF base Petiole Lamina All Answer :C

Discussion

20234.	Question : Broad-leaved forest oak are found in:
Answer» North coniferous forests Mediterranean EVERGREEN forest Temperate DECIDUOUS forest Tropical deciduous forest Answer :B

Discussion

20235.	Question :Broad funnel shaped space in the kidney, inner to hilum is
Answer» RENAL column renal PELVIS renal calyx renal sinus Answer :B

Discussion

20236.	Question : (a) Bring out the inheritance of chloroplast gene with on example. Chloroplast Inheritance
Answer» Solution :Chloroplast Inheritance: (i) DNA is the universal genetic material. Genes located in nuclear chromosomes fllow Mendelian inheritance.But certain traits are governed either by the chloroplast or mitochondrial genes known as extra nuclear inheritance. (ii) It is kind of Non-Mendelian inheritance. Since it INVOLVES cytoplasmic organelles such as chloroplast that act as inheritance vertors, it is also called Cytoplasmic inheritance. (iii) It is based on independent, self replicating extra chromosomal unit called plasmogene located in the chloroplast. (iv) IT is found in 4 O' Clock plant (Mirabilis jalapa). (v) Two types of VARIEGATED leaves namely (i) Dark green LEAVED plants (ii) Pale green leaved plants. (vi) When the pollen of dark green leaved plant (male) is transferred to the stigma of pale green leaved plant (female) and pollen of pale green laeved plant is transferred ot the stigma of dark green leaved plant, the `F_(1)` generation of both the crossed must be identical as per Mendelian inheritance. (vii) But in the reciprocal cross the `F_(1)` plant differs from each other. (viii) In each cross, the `F_(1)` plant reveals the character of the plant which is used as female plant. (ix) This inheritance is not through nuclear gene. It is due to the chloroplast gene found in the ovum of the female plant which contributes the cytoplasm during fertilization since the male gamete contribute only the nucleus but not cytoplasm. Pale Green leaved Plant (male) `underset(F_(1)" Dark Green leaved)underset(DARR)(xx)`Dark Green leaved Plant (Female)`""`DArk Green leaved Plant (Male) `underset(F_(1)" Pale Green leaved)underset(darr)(xx)`Pale Green leaved Plant (Female)

Discussion

20237.	Question : Briefly write the the methodlogy involved in this techique ?
Answer» SOLUTION :In DNA finger fingre printing ,the DNA MOLECULES are identified by a modern technique colled southern blotting. The major STEPS are: Isolation of DNA DIGESTION by RESTRICTION endonucleases

Discussion

20238.	Question : Bright coloured fleshy fruit are dispersed by
Answer» Insect Air Water Bird Answer :D

Discussion

20239.	Question : Briefly mention the contribution of T.H. Morgan in genetics.
Answer» Solution :T.H. Morgan put forth the chromosome theory of linkage from his work on fruit FLY (DROSOPHILA melanogaster). He ESTABLISHED the principle of linkage, discovered sex linkage and the technique of chromosome MAPPING. He wrote a book Theory of Gene. and was awarded Nobel PRIZE in 1933.

Discussion

20240.	Question : Briefly explaing the 'cutting' and 'ligation' of DNA during recombinant DNA technology or how is recombinant DNA produced ?
Answer» Solution :.Cutting. of DNA is by RESTRICTION ENZYMES. Purified DNA molecules are incubated with restriction ENDONUCLEASES to make the .cut. . This pro-cess is repeated in vector also . The .ligation. of DNA involves several processes. The cut out .GENE of inter-est. fromthe SOURCE DNA and the cut vector with space are mixed and DNAligase is added . This result in the preparation of recombinant DNA .

Discussion

20241.	Question : Briefly explain natural methods of birth control.
Answer» Solution :Perodic abstinence-couple should avoid coitus from 10th to 17th DAY of menstrual CYCLE. Coitus interruptus-male partner withdraws his penis from the bagina just before EJACULATION of SEMEN.

Discussion

20242.	Question : Brieflyexplain the usea of transgenicanimals .
Answer» Solution :Normal physiology and development: Trangenicanimals are specifically designedto allow studying about . Howthe genes regulated. How the gene affects normal functioningof body . How it affects growth and development E.g., insulin like growth factor . Theanimalsare madetransgnetic to know the biological EFFECT and result. Studyof disese : Transgenicof disease like cancers , cysticfibrosis , rheumatoidarthritis and Alzheimer.s Biological products : Transgenicanimalsare USED to produce biological product of human intereset. `alpha` 1-antitrypsin used to treatemphysema. PROTEINS for treatment of PKU andcysticfibrosis. Trangenic cow , Roiseproduce human protein enriched milk (2.4 gm/lit.human `alpha`- lactalbumin). Vaccine safety . Transgenic miceare beingdeveloped and USEIN testingthe safetyof vaccinesbeforetheyareusedfor humans . Polio vaccine is testedin mice . Chemicalsafety testing . THISIS also known as toxicity /safety testing . Transgenicanimalsare usedto knowthe effects of toxi chemicals .

Discussion

20243.	Question : Briefly explain the surface sterilization of explants.
Answer» Solution :The plants materials to be used for tissue culture should be surface sterilized by FIRST exposing the material in running TAP WATER and then treating it in surface sterilization agents like 0.1% mercuric chloride, 70% ethanol under aseptic CONDITION inside the Laminar Air Flow Chamber.

Discussion

20244.	Question : Name the male gamete in a flower. Explain its structure.
Answer» Solution :a. Pollen grains are the mature microspore. The WALL of the pollen grain is made up of outer exine and an inner intine. b. The exine is outerhard coat due to the prescnce of sporollenin, WHEREAS intine is made up of cellulose and pectin. c. The pollen grain has germpore through which the pollen tube germinate. d. Enclosed within the wall are two unequal cells. The larger one is called the vegetative cell and the smaller one is called the generative cell. e. The vegetative cell has abundant FOOD reserve, a large irregularly shaped nucleus and a floating generative cell in its cytoplasm. f. The generative cells produce two MALE gametes, which takes PART in double fertilization.

Discussion

20245.	Question : Briefly explain the structure of human insulin. What was the main challenge for production of insulin using rDNA technique?
Answer» Solution :The HUMAN insulin is synthesized by the `beta` cells of ISLETS of Langerhans in the pancreas. It is formed of 51 aminoacids which are arranged in two polypeptide chains, A and B. The polypeptide CHAIN A has 21 amino acids while the polypeptide chain B has 30 amino acids. Both A and B chains are attached together by DISULPHIDE bonds.

Discussion

20246.	Question : Briefly explainthe specialadaptations evolvedby parasites in accordancewiththeirlifestyles.
Answer» Solution :a. Loss ofunnecessarysenseorgans. B. PRESENCEOF adhesiveorgans orsuckers. c.Lossof digestivecapacity d .High repreoductive capacity .

Discussion

20247.	Question : Briefly explainthe needof constantinternalenvironmentfor organisms. Whatdo youmean byhomeostasis ?
Answer» Solution :A constantinternalenvironment isneeded to PERMIT all biochemicalreactionsand physicologicalfunctionto proceed withmaximum EFFICIENCY. Themaintenanceof a CONSTANT internal environmentbyorgansimsiscalledhomeostasis.

Discussion

20248.	Question : Briefly explain the different measures to reduce noise pollution.
Answer» SOLUTION :i. REDUCTIONOF noisefrom INDUSTRIES by usingsound absorbentmaterialsor by MUFFLING noise . ii. Delimiationof horn- free zonesaround hospitals andschools. iii. Limit the useof loudspeakers especially during 9 pm- 9am. IV. USeof crackers within permissiblesoundlevels.

Discussion

20249.	Question : What is male heterogamety? Explain sex determination in humans.
Answer» Solution :In human SEX determination is XX-XY type. MALES are heterogametic because they produce two types of SPERMS, ie., `50%` gametes carrying X chromosome and `50%` of gametes carrying Y - chromosome. Females are homogametic and produce X type of eggs. During fertilization, if egg fuses with x sperm, it DEVELOPS into female offspring. If egg fuses with sperm carrying Y chromosomes, it develops, into male offspring.

Discussion

20250.	Question : BrieflyexplainGause'scompetitiveexclusion principle .
Answer» SOLUTION :This principlestates thatcloselyrelatedspeciescompetingfor thesameresourcescannotcoexistindefinitedand thecompetitivelyinferiorone WILLBE eliminatedeventually.

Discussion

Explore topic-wise InterviewSolutions in .

Question : Bt cotton is regarded as an important achievement of genetic engineering. What does Bt stands for.

Question : Bt cotton is not

Question :Bt cotton is not(A) a GM plant(B) Insect resistant(C) a bacterial gene expressing system(D) resistant to all pesticides

Question : BT cotton is not :

Question : Bt. cotton is a well known example of application of Biotechnology in agricul ture. Bt. cotton reduces the use of pesticides. Explain.

Question : Bt - cotton has genes to repel

Question : Bt cotton is a disease resistant transgenic plants.

Question : Bt cotton genes repel

Question : Bt cotton has been produced by

Question : 'Bt Cotton''

Question : Bt corn been made resistant from corn borer disease by intoduction of the gene

Question : Bryophytes show an advancement over algae in :-

Question : Bryophytes have probably evolved from

Question : Bryophytes can be separated from algae because they

Question : Bryophytes comprise

Question : Bryophytes can be compared with amphibians since both are (i) Autotrophic (ii) Dependent on water for reproduction (iii) Without endoskeleton (iv) Devoid of impervious body surface (v) With separate sexes

Question : Bryophytes are not characterised by :

Question : Bryophytes are different than algae in

Question : Bryophytes are amphibians because

Question : Bryophytes and Pteridophytes produce a large number of male gametes but relatively vary few female gametes. Why ?

Question : Bryophyta are not tall plants due to:-

Question : Bryophyllum vegetatively multiples by adventitious buds where , water hyacinth by____

Question : Bryophyllum is the best example of propagation by...............

Question : Bryophyllum can be propagated vegetatively by:

Question : Brush border epithelium occurs in

Question : Brunner's glands occur in:

Question : Brunner's glands are found in submucosa of_____.

Question : Brown sugar is :

Question : Brown rust of wheat is caused by ...........

Question : Brown algae is characterised by th presence of

Question : Brooders pneumonia disease is connected with

Question : Broca's area is concerned with_____

Question : Broad part of leaf is

Question : Broad-leaved forest oak are found in:

Question :Broad funnel shaped space in the kidney, inner to hilum is

Question : (a) Bring out the inheritance of chloroplast gene with on example. Chloroplast Inheritance

Question : Briefly write the the methodlogy involved in this techique ?

Question : Bright coloured fleshy fruit are dispersed by

Question : Briefly mention the contribution of T.H. Morgan in genetics.

Question : Briefly explaing the 'cutting' and 'ligation' of DNA during recombinant DNA technology or how is recombinant DNA produced ?

Question : Briefly explain natural methods of birth control.

Question : Brieflyexplain the usea of transgenicanimals .

Question : Briefly explain the surface sterilization of explants.

Question : Name the male gamete in a flower. Explain its structure.

Question : Briefly explain the structure of human insulin. What was the main challenge for production of insulin using rDNA technique?

Question : Briefly explainthe specialadaptations evolvedby parasites in accordancewiththeirlifestyles.

Question : Briefly explainthe needof constantinternalenvironmentfor organisms. Whatdo youmean byhomeostasis ?

Question : Briefly explain the different measures to reduce noise pollution.

Question : What is male heterogamety? Explain sex determination in humans.

Question : BrieflyexplainGause'scompetitiveexclusion principle .