24277 + Interview Questions in Biology in Class 12 Page 283 InterviewSolution

14101.	Question : Isometric growth in found in
Answer» fish locust grasshopper All of these Answer :D

Discussion

14102.	Question : List out any five morphological adaptations of halophytes.
Answer» Solution :Morphological ADAPTATIONS The TEMPERATE halophytes are herbaceous but the TROPICAL halophytes are mostly bushy. In addition to the normal roots, many stilt roots are developed. A special type of negatively geotropic roots CALLED pneumatophores with pneumathodes to get sutficient aeration are also present. They are called breathing roots. Example: Avicennia. Presence of THICK cuticle on the aerial parts of the plant body. eaves are thick, entire, succulent and glossy. Some species are aphyllous (without leaves).

Discussion

14103.	Question : List four features which enable the Xeric plants to survive in the desert conditions.
Answer» SOLUTION :(i)thick cuticle (ii) STOMATA in deep pits (iii)Stomata closed during day time (iv) leaves MODIFIED into spines (CAM photosynthetic PATHWAY).

Discussion

14104.	Question : Isometric growth in not found in
Answer» mammals fishes locust grasshopper Answer :A

Discussion

14105.	Question : List down the advantages of conventional methods.
Answer» Solution :ADVANTAGES of conventional methods (i) The plants produced are genetically uniform. (ii) Many plants can be produced quickly by this method. (iii) Some plants PRODUCE little or no seeds, in others, the seeds produced do not germinate. In such cases, plants can be produced in a short period by this method. (iv) Some plants can be propagated more ecomically by vegetative propagation. EXAMPLE: Solanum tubersum. (v) Two different plants with desirable characters such as disease resistant and HIGH yield can be grafted and grown as a new plant with the same desirable characters.

Discussion

14106.	Question : List any two strategy adopted by bisexual flowers to prevent self-pollination.
Answer» Solution :Dichogamy: In bisexual flowers anthers and STIGMAS mature at different times, thus checking self-pollination. It is of two types. (1) Protandry: The stamens mature earlier than the stigmas of the flowers. Examples: Helianthus and Clerodendrum. Protogyny: The stigmas mature earlier than the stamens of the FLOWER. Examples: Scrophularia nodosa and Aristolochia bracteata. Self sterility/ Self-incompatibility : In some plants, when the pollen granin of a flower reaches the stigma of the same, it is unable to germinate or prevented to germinate on its own stigma. Examples: Abutilon, Passiflora. It is a GENETIC MECHANISM.

Discussion

14107.	Question : List any two methods of HIV prevention.
Answer» Solution :a. Sexual contact with infected PERSON. b. Transfusion of CONTAMINATED blood. c. Sharing of infected needles by DRUG abusers. d. From infected MOTHER to her child through PLACENTA.

Discussion

14108.	Question : List any two mechanisms by which a variant genotype is produced.
Answer» SOLUTION : CROSSING over, GENE MUTATION

Discussion

14109.	Question : Isolation of Bt gene from bacterium (Bacillus thuringiensis) was taken up in the year
Answer» 1977 1980 1997 1990 Solution :1980

Discussion

14110.	Question : List any two major causes other than anthropogenic causes of the loss of biodiversity.
Answer» Solution :(C) Alien (Exotic) species invasion : Introduction of alien species also causes the RISK of extinction. When alien species are introduced some of them turns INVASIVE and causes decline or extinction of indigenous species eg. Nile perch, a large predator fish, when introduced into the Lake Victoria in East AFRICA eventually led-to the extinction of an ecologically unique assemblage of more than 200 species of cichlid fish in the lake. Some well known invasive weed species like Parthenium (carrot grass), Lantana and water hyacinth (Eichomia) had caused immense environmental damage and posed threat to our native species. The recent introduction of African catfish (Clarias gariepinus) illegally for aquaculture purpose is posing a threat to the indigenous cat fishes of Indian rivers. (D) Co-extinctions : When a species becomes extinct, the plant and animal species associated with it, in an obligatory way also become extinct. eg. if a species of fish become extinct, all the parasites unique/specific to that fish also face extinction. Similarly in case of a co-evolved plant pollinator MUTUALISM, extinction of ONE species invariably leads to the extinction of the other.

Discussion

14111.	Question : Isolation of blood to treat Haemophilia A is practically impossible. Give reason.
Answer» SOLUTION :a) REQUIREMENT of large quantity of blood. b) RISK of transmission of blood RELATED DISEASES like AIDS.

Discussion

14112.	Question : List any two bioactive molecules of fungal origin and explain how those molecules help in restoring good health in humans.
Answer» Solution :a) Cyclosporin A- produced by the fungus Trichoderma polysporum, is used as an IMMUNO suppressive agent in organ- transplant patients. b) Statins- produced by the yeast Monascus purpureus have been commercialised as blood cholesterol LOWERING agents by COMPETITIVELY inhibiting the ENZYME responsible for SYNTHESIS of cholesterol.

Discussion

14113.	Question : Isolated population with the potential for rapid speciation are
Answer» SMALL in number large in number dimorphic inbreed Answer :A

Discussion

14114.	Question : List any two adverse effects of particulate matter on human health.
Answer» Solution :Particulate matter when inhaled deep into the lungs they cause : (i) BREATHING and RESPIRATORY symptoms (ii) IRRITATION (iii) Inflammations (iv) DAMAGE to the lungs and PREMATURE deaths.

Discussion

14115.	Question : Isolated chloroplast cannot synthesize starch through dark phase inspite of possessing stroma and dark phase enzymes It is due to absence of
Answer» Cytosol for exporting G3P Photophosphorylation Suitable HYDROGEN ACCEPTOR Carbondioxide for DARK PHASE reactions Answer :D

Discussion

14116.	Question : List any two adaptive features evolved in parasites enabling them to live successfully on their host?
Answer» SOLUTION :PRESENCE of haustorial ROOTS INSIDE the host PLANT to absorb nutrients.

Discussion

14117.	Question : List any three types of Innate Immunity barriers and give an example for each
Answer» Solution :a) Physical barriers These barriers do not ALLOW pathogens and FOREIGN agents to enter the body, eg., skin, mucous membranes of digestive, respiratory and urinogentical tracts trapping micro- organisms. b) Physicological barriers Sweat, tears, ACID in the stomach and saliva prevent microbial GROWTH c) Cellular barriers WBCs (Polymorphonuclear leukocytes and monocytes, natural killer lymphocytes) and macrophages PHAGOCYTOSE and destroy microbes. d) Cytokine barriers Interferons produced by virus - infected cells prevent from further viral infection

Discussion

14118.	Question : Isogametes are found in(A) cladophora and ulothrix(B) cladophora and fucus(C) fucus and ulothrix(D) oedogonium, fucus and ulothrix
Answer» CLADOPHORA and ULOTHRIX cladophora and FUCUS fucus and ultothrix OEDOGONIUM, fucus and ulothrix ANSWER :A

Discussion

14119.	Question : List any three special abilities of humans which have evolved due to large-sized brain.
Answer» SOLUTION :SPEECH, REASONING, CONCEPTUALISATION

Discussion

14120.	Question : List any three important characteristics of a population and explain :
Answer» Solution :• Three important characteristics of a population are : • Density : It is expressed as the total number of individuals per UNIT area or volume at a given time. The SIZE of the population is determined by the AVAILABLE resources nutrients, water etc. at a given time and other group properties such as natality, mortality and age structure. • Natality : It is the increase in the number of individuals in a population under given environmental conditions. Birth, HATCHING, germination and even vegetative PROPAGATION cause increase in the number of individuals. • Mortality : The loss of individuals due to death in a population under given environmental conditions is called mortality.

Discussion

14121.	Question : Isogametes are(A) morphologically similar(B) physiologically similar(C) motile and has flagella(D) all the above
Answer» Solution :In some ALGAE similar TYPES of gametes are PRODUCED called as ISOGAMETES.

Discussion

14122.	Question : List any three important characteristics of population and explain them.
Answer» Solution :(i) Population DENSITY: It is the number of individuals of a species PER unit area or volume at a given time. (ii) Natality: It is increase in number of individuals in population under given ENVIRONMENTAL condition, birth, hatching, germination and even vegetative propagation causes increase in number of individuals. (iii) Mortality: It is the LOSS of individuals DUE to death in a population under given environmental condition.

Discussion

14123.	Question : Islets of Langerhans are patches of endocrine cells in :
Answer» Liver Pancreas Kidney Stomach Answer :B

Discussion

14124.	Question : Listany three important characteristicof a population and explain .
Answer» Solution :A populationhas characteristic not shown by itsindividual members .Each populationhas natalitymortality dispersal bitoc ptermatialsexratiopatternof distribution variatin in numbers etc. a. Natality(BIRTH)rate thebirthrateof populationrefersto theaveragenumber of youngonesproducedby birthor germinationper unittime.The maximumbirthrate a speciescan achieveunderidealenvirommental conditionis calledpotentialnatalityalsocalledbioticpotential. Mortality(death )rate Thedeathrateof a POPULATIONIS the AVERAGENUMBER of individulasthat dieper unittime. Thedeathreate isexpressed as change numbers withrespectto membersof teh population CDispersal Individulas in a population disperse at ONE TI me or the otherduringtheir life . Thesereveal immingration or emigration.

Discussion

14125.	Question : List any three characteristic features of multiple allele.
Answer» Solution :`` MULTIPLE alleles of a series always OCCUPY the same locus in the homologous chromosome. `` Therefore, no crossing over occurs within the alleles of a series. `` Multiple alleles are always responsible for the same character. `` The wild type alleles of a series exhibit dominant character WHEREAS MUTANT type will influence dominance of an intermediate phenotypic EFFECT.

Discussion

14126.	Question : List any three advantages of micropropagation.
Answer» Solution :`` TISSUE culture can be carried out in any SEASON to PRODUCE plants . `` Plants which do not produce viable seeds and seeds that are difficult to germinatecan be protapgeted by tissue culture. `**` CELLS can be genetcally modified and transformedusing tissue culture.

Discussion

14127.	Question : islands of phloem are found in the wood of strychnos. This is dueto
Answer» development from wood parenchyma differentiation form VASCULAR ray intrusion of phloem through vascularray formation form SEPARATED cambial strip. Answer :d

Discussion

14128.	Question : islands of parenchyma are embedded in wood of
Answer» urtica Entada chenopodium Artemesia Answer :a

Discussion

14129.	Question : List any six traits in garden pea which Mendel studied in his breeding experiments.
Answer» SOLUTION :(a) stem height (b) pod SHAPE (c) Pod colour (d) seed shape (e) seed colour (F) flower colour

Discussion

14130.	Question : Isinglass, a type of by-product of fish industry is principally used for
Answer» Feeding cattle, pigs and poultry Preparation of paints and VARNISHES O Clarification of vinegar, WINES and beer Production of insulin Answer :C

Discussion

14131.	Question : List any four hormones secreted by placenta.
Answer» Solution :a. HUMAN Chorionic Gonadotropin(hCG) b. Human Placental Lactogen (HPL) c. Estrogens d. Progestogens.

Discussion

14132.	Question : _____island was considered to be nature's laboratory by Darwin.
Answer» Hawaii Andaman nicobar Cyelone Galapagos Answer :D

Discussion

14133.	Question : List any four characters of genetic code?
Answer» SOLUTION :(1) Genetic code is universal. (2) It is triplet in nature. (3) Itis NON overlapping and highly sequential. (4) It is DEGENERATE.

Discussion

14134.	Question : ____is used for commercial production of ethanol.
Answer» ANSWER :SACCHAROMYCES serevisiae

Discussion

14135.	Question : List any four characters that are employed in human population census.
Answer» SOLUTION :• (i) Birthrates (Natality) (II) Death RATES (Mortality)(iii) Sex RATIO (iv) Age distribution.

Discussion

14136.	Question : Is there any relationship between dedifferentiation and the higher degree of success achieved in plant tissue culture experiments ?
Answer» Solution :YES, the cells that has LOST the capability of division can regain the capacity of division through dedifferentiation. So, in plant TISSUE culture EXPERIMENTS more SUCCESS is achieved.

Discussion

14137.	Question : Is their any possibilities to tranfer a suitable desirable gene to host plant without vector? Justify you answer.
Answer» Solution :YES, it is possible to transfer a SUITABLE desired GENE to a host plant using CERTAIN chemicals, microinjection method, electroporation or by BIOLISTICS.

Discussion

14138.	Question : List any four adverse effect of noise.
Answer» Solution :HIGH BLOOD pressure Stress RELATED ailments SLEEP DISRUPTION Hearing impairment

Discussion

14139.	Question : Is there any population in Kerala having sickle cell anaemia? What is the reason of this genetic defect? Does it help the people in preventing any other diseases like malaria?
Answer» SOLUTION :Yes. In high altitude persons. It is a genetic DEFECT CHARACTERISED by sickle shaped RBC with ABNORMAL HB.

Discussion

14140.	Question : List any four applications of DNA fingerprinting.
Answer» Solution :DNA fingerprinting is USED in : DNA FORENSICS, for identification of criminals. DNA fingerprinting, for solving PATERNITY DISPUTES determining POPULATION and genetic diversities studying the breeding patterns of animals facing the danger of extinction.

Discussion

14141.	Question : Is there a relationship between the size of an organism and its life span ? Give two examples in support of your answer.
Answer» Solution :Life spans of organisms are not necessarily correlated with their SIZES. The sizes of crows and parrots are not very different YET their life spans show a WIDE difference. Life span of crow is 15 year and of parrot is 140 years. A MANGO tree has a much shorter life span (200 years) as compared to peepal tree (2500 years).

Discussion

14142.	Question : List any four applications of tissue culture.
Answer» Solution :The modern techniques of BIOLOGICAL CONTROL of weeds involving the use of insects and microorganisms to kill the weeds are called BIOHERBICIDES. Cochineal insect to destroy cacti, FUNGUS Phytophthora palmivora to control growth of milk-weed vines are EXAMPLES of biocides

Discussion

14143.	Question : Is there a cure for AIDS ?
Answer» Solution :Till today there is no accurate method available for the treatment of AIDS. Treatment with anti-retroviral drugs is only partially effective. They can only prolong the life of the patients but cannot prevent death. There is no vaccination available. It is absolutely incurable disease. National AIDS Control ORGANIZATION (NACO), World Health Organization(WHO). Non Government Organization (NGO). The above mentioned organization has started numerous programmes to prevent the SPREADING of HIV infection.

Discussion

14144.	Question : List any four advantages of genetically modified crop plants over their wild/ domesticated relatives.
Answer» SOLUTION :Advantages of genetically modified plants are,i. MAKE crops more TOLERANT to abiotic stresses. (Cold, drought, salt, heat) ii. Reduce reliance on chemical PESTICIDES. (Pest resistant crops) iii. Help to reduce post harvest losses.Biotechnology and its Applications iv. Increase the efficiency of mineral usage by plants.v. Enhance nutritional value of food. e.g. Vitamin A enriched rice.

Discussion

14145.	Question : List any four advantages of genetically modified crop plants over their wild/domesticated relatives.
Answer» SOLUTION :(i) Improvementof nutritional quality . `""` (II) BETTER NITROGEN fixation. (III) Production of disease resistantplant. `""` (iv) To reduce post - harvest losses.

Discussion

14146.	Question : Is the use of contraceptives justified? Give reasons.
Answer» Solution :yes. 1.Population GROWTH at this rate would lead to an aboustly scarcity of basics REQUIREMENT like FOOD, shelter ,clothing,etc. 2.There will be an increases in STDS including AIDs.

Discussion

14147.	Question : List any six features of genetic code.
Answer» Solution :Structural genes: .Z. for `beta` - gataclosidase, `gamma` for galactoside permease, .A. for galactosidetransacetylase. Regulatory gene - Regulator, promoter and operator Operon - off (SWITCH off) - in the absence of lactose in the medium regulator directs the SYNTHESIS of repressor protein that finds to operator. Operator gets repressed. RNA polymerase cannot bind to the promoter since a part of operator overlaps promoter. Structural genes are switched-off and therefore neither mRNA nor the ENZYMES are synthesized. Operor - On (switch on) - In the presence of lactose in the medium represent binds to lactose forming lactose-repressor complex.. Operator is derepresented RNA polymerase INTERACTS with the exposed promoter. Structural genes are switched on and therefore a polycistronic mRNA is synthesized followed by the synthesis of the enzymes.

Discussion

14148.	Question : Is the use of contraceptives justified ? Give reasons.
Answer» Solution :An IDEAL contraceptive should be user friendly, easily available, effective and reversible with no or least SIDE effect. It should also not interfere with the sexual drive, desire and the sexual act of the user. So it is ADVISABLE to use contraceptive to check the population EXPLOSION.

Discussion

14149.	Question : List all the wastethat yougenerate, at home, schoolor duringyour tripsto other place,couldyou very easily reduce? Which wouldbe difficult or ratherimpossibleto reduce ?
Answer» Solution :Food wastes , plastic bottlesand COVERS , used cloths ETC are the COMMON wastes that THEWE produce . Of these , plasticwastercan bereduced byotherbiodegradable materials .

Discussion

14150.	Question : ____is the universal hydrogen acceptor.
Answer» ANSWER :NAD

Discussion

Explore topic-wise InterviewSolutions in .

Question : Isometric growth in found in

Question : List out any five morphological adaptations of halophytes.

Question : List four features which enable the Xeric plants to survive in the desert conditions.

Question : Isometric growth in not found in

Question : List down the advantages of conventional methods.

Question : List any two strategy adopted by bisexual flowers to prevent self-pollination.

Question : List any two methods of HIV prevention.

Question : List any two mechanisms by which a variant genotype is produced.

Question : Isolation of Bt gene from bacterium (Bacillus thuringiensis) was taken up in the year

Question : List any two major causes other than anthropogenic causes of the loss of biodiversity.

Question : Isolation of blood to treat Haemophilia A is practically impossible. Give reason.

Question : List any two bioactive molecules of fungal origin and explain how those molecules help in restoring good health in humans.

Question : Isolated population with the potential for rapid speciation are

Question : List any two adverse effects of particulate matter on human health.

Question : Isolated chloroplast cannot synthesize starch through dark phase inspite of possessing stroma and dark phase enzymes It is due to absence of

Question : List any two adaptive features evolved in parasites enabling them to live successfully on their host?

Question : List any three types of Innate Immunity barriers and give an example for each

Question : Isogametes are found in(A) cladophora and ulothrix(B) cladophora and fucus(C) fucus and ulothrix(D) oedogonium, fucus and ulothrix

Question : List any three special abilities of humans which have evolved due to large-sized brain.

Question : List any three important characteristics of a population and explain :

Question : Isogametes are(A) morphologically similar(B) physiologically similar(C) motile and has flagella(D) all the above

Question : List any three important characteristics of population and explain them.

Question : Islets of Langerhans are patches of endocrine cells in :

Question : Listany three important characteristicof a population and explain .

Question : List any three characteristic features of multiple allele.

Question : List any three advantages of micropropagation.

Question : islands of phloem are found in the wood of strychnos. This is dueto

Question : islands of parenchyma are embedded in wood of

Question : List any six traits in garden pea which Mendel studied in his breeding experiments.

Question : Isinglass, a type of by-product of fish industry is principally used for

Question : List any four hormones secreted by placenta.

Question : _____island was considered to be nature's laboratory by Darwin.

Question : List any four characters of genetic code?

Question : ____is used for commercial production of ethanol.

Question : List any four characters that are employed in human population census.

Question : Is there any relationship between dedifferentiation and the higher degree of success achieved in plant tissue culture experiments ?

Question : Is their any possibilities to tranfer a suitable desirable gene to host plant without vector? Justify you answer.

Question : List any four adverse effect of noise.

Question : Is there any population in Kerala having sickle cell anaemia? What is the reason of this genetic defect? Does it help the people in preventing any other diseases like malaria?

Question : List any four applications of DNA fingerprinting.

Question : Is there a relationship between the size of an organism and its life span ? Give two examples in support of your answer.

Question : List any four applications of tissue culture.

Question : Is there a cure for AIDS ?

Question : List any four advantages of genetically modified crop plants over their wild/ domesticated relatives.

Question : List any four advantages of genetically modified crop plants over their wild/domesticated relatives.

Question : Is the use of contraceptives justified? Give reasons.

Question : List any six features of genetic code.

Question : Is the use of contraceptives justified ? Give reasons.

Question : List all the wastethat yougenerate, at home, schoolor duringyour tripsto other place,couldyou very easily reduce? Which wouldbe difficult or ratherimpossibleto reduce ?

Question : ____is the universal hydrogen acceptor.