24277 + Interview Questions in Biology in Class 12 Page 20 InterviewSolution

951.	Question : When both ovaries of human are removed then which hormone is decreased in blood :-
Answer» Oxytocin Prolactin Estrogen Gonadotropin RELEASING factor Answer :C

Discussion

952.	Question : When bond between firstand second phosphate of ATP is hydrolysed,the amount of energy released(at pH 7)is
Answer» 1200cal 3000 cal 1500-1800 cal 6.5 kcal Solution :NA

Discussion

953.	Question : When BOD of sewage is reduced significantly the effluent is passed into a ..........
Answer» AERATION TANK SETTLING tank Anaerobic SLUDGE DIGESTER underground digester tank Solution :settling tank

Discussion

954.	Question : When blood levels of glucocorticoids raises then the secretion of
Answer» TSH decreases Somatocrinin increases FSH Increases ACTH decreases Answer :D

Discussion

955.	Question : When birth time is near, two chemical signals associated and produces real parturition pain / labour pain.
Answer» Solution :Some cells of embryo start producing oxytocin. That excites to release prostaglandian of PLACENTA. These both hormones induces consistent and powerful contraction of uterus. At this stage, signals of oxytocin are released from posterior pituitary gland. COMBINED effects of increased level of oxytocin and prostaglandin PROMOTE promote LABOUR pain. Due to strong contraction more oxytocin is released. As a result powerful contraction occurs. That penetrates foetus deep from abdomen. This takes out foetus from uterus immediately after that child is delivered.

Discussion

956.	Question : When beet root cylinders are washed an then placed in hot water. The water turns red. This is due to
Answer» Piasma MEMBRANE LOSES its function hence pigments COME out of beetroot Plasma membrane is functional and ALLOWED anthocyanin to come out Anthocyanin get denatured None of the above Answer :A

Discussion

957.	Question : When are the chromosomes seen in the form of chromatin network?
Answer» SOLUTION :In interphase, CHROMOSOMES are seen in the FORM of CHROMATIN NETWORK.

Discussion

958.	Question : When are bivalents of chromosomes first clearly visible in meiosis ?
Answer» Leptotene Diplotene Pachytene Diakinesis Answer :C

Discussion

959.	Question : When and Where does spermatogenesis occur in human male ? (b) Draw a diagram of a mature human male gamete. Label the following parts: acrosome, nucleus, middle piece and tail. (c) Mention the functions of acrosome and middle piece.
Answer» SOLUTION :Intestes, the immature male germ cells (spermatogonia) produce sperms by spermatogenesis that begin at PUBERTY (c) Function of acrosome : A plasma membrane envelops the Whole body of sperm. The sperm head contains an elongated haploid nucleus, the anterior portion of which is covered by a cap-like structure called acrosome. The acrosome is filled With enzymes that help FERTILISE the ovum. Function of MIDDLE piece : Middle piece contains a number of MITOCHONDRIA, that provide energy for the motility of sperms.

Discussion

960.	Question :When and why do snails go into aestivation?
Answer» Solution :Snails UNDERGO aestivation during summer to AVOID HEAT and OVERCOME DESSICATION

Discussion

961.	Question : When and why does a plant breeder employ this technique?
Answer» Solution :Emasculation is the EMPLOYED by a plant breeder to obtain commercially superior VARIETIES of crop plants in artificial hybridisation Emasculation is employed to ensure that the pollen grains only from the parent plant with DESIRED CHARACTERS should pollinate on the stigma. Emasculation PREVENTS self pollination.

Discussion

962.	Question :When and where are primary oocytes formed in a human female ? Trace the development of these occytes till ovulation (in menstrual cycle). How do gonadotropins influence this developmental process ?
Answer» Solution : Oogenesis : (i) The process of formation of a mature female gamete or ova in the ovary is KNOWN as oogenesis. (ii) Germ cells of female foetus divide to produce oogonia which later grow into ovarian follicles. (iii) Oogonia start dividing and enter into prophase -I of the miotic division and get temporarily arrested at that stage, called primary oocytes are ENCLOSED by a layer of granulosa cells, the follicle cells, and known as primary follicle. (iv ) The primary follicles get surrounded by more layers of granulosa cells and a thecal layer known as secondary follicles. (v) The secondary follicle soon transforms into a tertiary follicle which is characterised by a fluid-filled cavity called antrum. (vi) Primary oocyte undergoes first meotic division and produce two haploid cells: a large haploid secondary oocyte and a small first polar body. Secondary oocyte moves into the fallopian tube. (vii) When a sperm enters its cytoplasm, secondary oocyte completes meosis-II. ( viii) The secondary oocyte undergoes the second meotic division and produces a mature ovum and a second polar body. (ix) Polar bodies have no function and eventually degenerate. (x) Mature follicle of Graafian follicle ruptures to RELEASE the ovum from the ovary by the process called OVULATION. Effect of gonadotropins : The primary follicle in the ovary grows and becomes a fully mature Graffian follicle. The endometrium of the UTERUS is regenerated due to the secretion of LH and FSH from anterior pituitary and ovarian hormone, estrogen. It lasts for about 14 days. Rapid selection of LH (LH surge) induces rupture of Graafian follicle and thereby leading to ovulation (release of ovum). For figure : See Q. 28 (or), Set-I, Delhi Board-2008

Discussion

963.	Question : When an organism is benefitted without affecting the other is called :
Answer» Mutualism Symbiosis Commensalism Parasitism ANSWER :C

Discussion

964.	Question : When an oak tree is kept in a poisonous solution, that rises to the top of the tree, even then the tree is ready to take another supply of poisonous solution followed by uptake of even pure water. This shows that
Answer» Living cells are not involved in ASCENT of sap Living cells play a MAJOR ROLE in ascent of sap Both xylem and phloem play a major role in ascent of sap Living cells play 60% role and VESSELS of xylem play 40% role in ascent of sap Answer :A

Discussion

965.	Question : When and at what end does the tailing' of hn RNA take place?
Answer» Solution :After the PROCESS of SPLICING the HN RNA undergoes capping and tailing. In tailing, ADENYLATE residues (200-300) are ADDED at 3-end.

Discussion

966.	Question : When an impulse passes, the membrane is depolarized and the charge of the cells is :-
Answer» Outside positive and INSIDE negative Inside positive and outside negative Both sides have ZERO potential Both sides are electronegative ANSWER :B

Discussion

967.	Question : When an allele of one gene suppresses an allele of another gene,the phenomenon is called :
Answer» DOMINANCE Suppression Epistasis Inactivation Answer :C

Discussion

968.	Question : When an alien DNA fragment is linked with the origin of replication, so that this alien piece of DNA can replicate and multiply itself in the host organism, then this can be called as
Answer» GENE transfer gel ELECTROPHORESIS gene cloning transformation Answer :C

Discussion

969.	Question : When alloxan is injuected into experimental animal, glycosuria results because of
Answer» STIMULATION of SYMPATHETIC nerves Lowering of RENAL threshold Damage of brain Necrosis of BETA cells of Islet of Langerhans Answer :4

Discussion

970.	Question : When agriculture began ?
Answer» Before MILLIONS of the YEAR Before THOUSANDS of the year Before LACS of the year Before CRORES of the year Solution :Before thousands of the year

Discussion

971.	Question : When a yellow mouse were crossed to another yellow mouse,the F_(1) generation produces yellow and brown-black mice in the ration 2:1. The yellow mice are never homozygous. The reason is
Answer» Homozygous YELLOW cannot SURVIVE due to lethal EFFECT of genes Yellow mice are not very SUITABLE to live There is no formation of ZYGOTES with homozygous yellow constitution None of the above Answer :A

Discussion

972.	Question : When a cell is placed in hypotonic solution, water moves into the cell , this flow is called________.
Answer» ANSWER :ENDOSMOSIS

Discussion

973.	Question : When a yeast produces wine, which is not formed ?
Answer» Acetaldehyde Ethyl ALCOHOL `CO_2` ACETYL coenzymeA Answer :D

Discussion

974.	Question : When a wheat variety of red kernel is crossed with white kerneled wheat, the F_(2)ratio would be
Answer» 1:10:4:1 `9:7` 1:2:4:2:4:2:1 1:4:6:4:1 Answer :D

Discussion

975.	Question : When a woman heterozygous for A blod group heterozygous non albino marries a man who is heterozygous non albino and heterozygous for B blood group. The probable kindsof phenotypes in their progeny
Answer» 4 9 8 6 Answer :D

Discussion

976.	Question :When a tall plant with round seeds ( TTRR ) crossed with a dwarf plant with wrinkled seeds ( ttrr ) , the F_1 generation consists of tall plant with round seeds . What would be the proportion of dwarf plant with wrinkled seeds in F_1 -generation ?
Answer» `1/4` `1/16` 0 `1/2` ANSWER :C

Discussion

977.	Question : When a single gene influences multiple traits then the phenomenon is called ...........
Answer» PLEIOTROPY Polygenic INHERITANCE EPISTASIS ATAVISM ANSWER :A

Discussion

978.	Question :When a species is considered as locally extinct?
Answer» Solution :A SPECIES is CONSIDERED to be locally EXTINCT when it is no longer found in an area it once inhabited but is still found ELSEWHERE in the wild.

Discussion

979.	Question : When a segment of a chromosome breaks and later rejoins after 180^@rotation, it is known as
Answer» DELETION DUPLICATION INVERSION interstitial translocation ANSWER :C

Discussion

980.	Question : When a pure strain of tallplants (TT) with round seeds (RR) is crossed with a pure strain of short plants (tt) with wrinkled seeds (rr), an F_(1) generation is produced. The alleles for short and wrinkled are recessive to those for tall and round, respectively. When these F_(1) plants self-pollinate, what proportion of the F_(2) generation is short with wrinkled seeds ?
Answer» 0 `(1)/(16)` `(1)/(2)` `(9)/(16)` ANSWER :B

Discussion

981.	Question :When a red flowered Antirrhinum plant was crossed with a white flowered Antirrhinum plant, the F_1 offspring had pink flowers. Mention: (a) The genotype of F_1plants (b) The reason why it did not bear the parental red or white flower colours.
Answer» SOLUTION : (a) Rr, (b) It is due to phenomenon of INCOMPLETE dominance, where dominant GENE in heterozygous CONDITION has reduced its expression in `F_1`generation so that each of them expresses itself PARTIALLY.

Discussion

982.	Question : When a red flowered. Antirrhinum plant was crossed with a white flowered Antirrhinum plant, the F_1 offspring had pink flowers. Mention (a) the genotype of F_1 plant, and(b) the reason why it did not bear the parental red or white flower colours?
Answer» SOLUTION :(a) Rr { presuming PARENTS had genotypes (RR) and (rr)} (b) It shows INCOMPLETE DOMINANCE.

Discussion

983.	Question : When a process is elevated to large scale, the stage between laboratory scale and manufacuring unit is known as
Answer» Bioeactor scale Pilot PLANT scale Support GROWTH system Suspended growth system Answer :B

Discussion

984.	Question : When a plant with 6 feet height was crossedwith a plant with 4 feet height, than plants with 5 feet height was obtained. When it is selfed, 1/256 plants having 4 feet height and 1/256 plants having 6 feet height was obtained. Find out how many polygenes are controlling this inheritance
Answer» 4 3 2 6 Answer :A

Discussion

985.	Question : When a pressure greater than atmospheric pressure is applied to pure water,its ψw
Answer» Increases Decreases Becomes zero Remains same Answer :B

Discussion

986.	Question : When a plant wilts, sequence of events will be as
Answer» EXOSMOSIS, DEPLASMOLYSIS, PLASMOLYSIS, temporary and PERMANENT wilting Exosmosis, plasmolysis, deplasmolysis, temporary and permanent wilting Exosmosis, temporary and permanent wilting None of the above Answer :C

Discussion

987.	Question : When a plant of F_1 generation is crossed with the homozygous dominant parent, it is known as _
Answer» SOLUTION :BACK CROSS

Discussion

988.	Question : When a physician informs a patient that his blood pressure reading is 160/90 , she refers respectively to
Answer» systolic pressure of the RIGHT ventricle systolic pressure of the AORTA and diastolic pressure in the superior vena cava systolic and diastolic pressures of the brachiral artery blood pressure in the veins of the arm SOLUTION :Blood pressure is usually measured by placing the sphygmomanometer cuff around the arm compressing the brachial artery and vein. Maximum blood pressure is obtained during ventricular contraction (systole): in our case 160. MINIMUM blood pressure indicates ventricular rest (diastole): in our case 90

Discussion

989.	Question : When a person suffers from marked fall in B.P. it is helpful to administer him the following hormone
Answer» Insulin Thyroxine Growth hormone Adrenaline Answer :4

Discussion

990.	Question : When a person is injected with antiserum, the type of immunity developed is
Answer» NATURAL active Artificial active Natural passive Artificial passive Answer :D

Discussion

991.	Question : When a particular characteristic of an individual, e.g. petal colour, shows variation among the offspring produced after the indiviual is selfed, it is said to be
Answer» Pure-breeding True-breeding HOMOZYGOUS HETEROZYGOUS ANSWER :D

Discussion

992.	Question : When a neuron is in resting state, i.e., not conducting any impulse, the axonal membrane is :
Answer» COMPARATIVE more permeble of `K^+` ions and nearly IMPERMEABLE to `Na^+` ions Comparatively more PERMEABLE to `Na^+` ions and nearly impermeable to `K+ ions EQUALLY permeable to both `Na^+` and `K^+` ions Impermeable to both `Na^+` and `K^+` ions Answer :A

Discussion

993.	Question : When a particle chromosome is present in three copies,the cell is a……………
Answer» SOLUTION :TRISOMIC

Discussion

994.	Question : When a particular chromosome rejoins in reverse orientation ,mutation work in geneties.
Answer» SOLUTION :INVERSION

Discussion

995.	Question : When a neural signal reaching the neuromuscular junction releases acetylcholine, an action potential is generated first in
Answer» SARCOLEMMA Sarcoplasmic reticulum Sarcosomes SARCOMERES ANSWER :A

Discussion

996.	Question : When a nerve fibres is stimulated the inside of the membrane becomes :
Answer» Filled with ACETYL CHOLINE NEGATIVELY charged POSITIVELY charged Neutral Answer :C

Discussion

997.	Question : When a mutation is limited to the substitution of one nucleotide for another , it is called :
Answer» translocation point MUTATION BASE inversion sugar PHOSPHATE deletion Answer :D

Discussion

998.	Question : When a muscle bends one part upon the other, it is called
Answer» abductor regulator extensor flexor ANSWER :D

Discussion

999.	Question : When a microspore mother cell with 40 chromosomes undergoes meiosis each of the four resulting cell has(A) 80 chromosomes(B) 20 chromosomes(C) 10 chromosomes(D) 40 chromosomes
Answer» 80 chromosomes 20 chromosomes 10 chromosomes 40 chromosomes Answer :B

Discussion

1000.	Question : When a man inhales air containing normal concentration of O_2 as well as CO he suffers from suffocation because
Answer» CO reacts with `O_2` REDUCING its PERCENTAGE in air Haemoglobin combines with CO instead of `O_2` and forms carboxyhaemoglobin CO affects DIAPHRAGM and INTERCOSTAL muscles CO affects the NERVES of the lungs Answer :B

Discussion

Explore topic-wise InterviewSolutions in .

Question : When both ovaries of human are removed then which hormone is decreased in blood :-

Question : When bond between firstand second phosphate of ATP is hydrolysed,the amount of energy released(at pH 7)is

Question : When BOD of sewage is reduced significantly the effluent is passed into a ..........

Question : When blood levels of glucocorticoids raises then the secretion of

Question : When birth time is near, two chemical signals associated and produces real parturition pain / labour pain.

Question : When beet root cylinders are washed an then placed in hot water. The water turns red. This is due to

Question : When are the chromosomes seen in the form of chromatin network?

Question : When are bivalents of chromosomes first clearly visible in meiosis ?

Question : When and Where does spermatogenesis occur in human male ? (b) Draw a diagram of a mature human male gamete. Label the following parts: acrosome, nucleus, middle piece and tail. (c) Mention the functions of acrosome and middle piece.

Question :When and why do snails go into aestivation?

Question : When and why does a plant breeder employ this technique?

Question :When and where are primary oocytes formed in a human female ? Trace the development of these occytes till ovulation (in menstrual cycle). How do gonadotropins influence this developmental process ?

Question : When an organism is benefitted without affecting the other is called :

Question : When an oak tree is kept in a poisonous solution, that rises to the top of the tree, even then the tree is ready to take another supply of poisonous solution followed by uptake of even pure water. This shows that

Question : When and at what end does the tailing' of hn RNA take place?

Question : When an impulse passes, the membrane is depolarized and the charge of the cells is :-

Question : When an allele of one gene suppresses an allele of another gene,the phenomenon is called :

Question : When an alien DNA fragment is linked with the origin of replication, so that this alien piece of DNA can replicate and multiply itself in the host organism, then this can be called as

Question : When alloxan is injuected into experimental animal, glycosuria results because of

Question : When agriculture began ?

Question : When a yellow mouse were crossed to another yellow mouse,the F_(1) generation produces yellow and brown-black mice in the ration 2:1. The yellow mice are never homozygous. The reason is

Question : When a cell is placed in hypotonic solution, water moves into the cell , this flow is called________.

Question : When a yeast produces wine, which is not formed ?

Question : When a wheat variety of red kernel is crossed with white kerneled wheat, the F_(2)ratio would be

Question : When a woman heterozygous for A blod group heterozygous non albino marries a man who is heterozygous non albino and heterozygous for B blood group. The probable kindsof phenotypes in their progeny

Question :When a tall plant with round seeds ( TTRR ) crossed with a dwarf plant with wrinkled seeds ( ttrr ) , the F_1 generation consists of tall plant with round seeds . What would be the proportion of dwarf plant with wrinkled seeds in F_1 -generation ?

Question : When a single gene influences multiple traits then the phenomenon is called ...........

Question :When a species is considered as locally extinct?

Question : When a segment of a chromosome breaks and later rejoins after 180^@rotation, it is known as

Question :When a red flowered Antirrhinum plant was crossed with a white flowered Antirrhinum plant, the F_1 offspring had pink flowers. Mention: (a) The genotype of F_1plants (b) The reason why it did not bear the parental red or white flower colours.

Question : When a red flowered. Antirrhinum plant was crossed with a white flowered Antirrhinum plant, the F_1 offspring had pink flowers. Mention (a) the genotype of F_1 plant, and(b) the reason why it did not bear the parental red or white flower colours?

Question : When a process is elevated to large scale, the stage between laboratory scale and manufacuring unit is known as

Question : When a plant with 6 feet height was crossedwith a plant with 4 feet height, than plants with 5 feet height was obtained. When it is selfed, 1/256 plants having 4 feet height and 1/256 plants having 6 feet height was obtained. Find out how many polygenes are controlling this inheritance

Question : When a pressure greater than atmospheric pressure is applied to pure water,its ψw

Question : When a plant wilts, sequence of events will be as

Question : When a plant of F_1 generation is crossed with the homozygous dominant parent, it is known as _

Question : When a physician informs a patient that his blood pressure reading is 160/90 , she refers respectively to

Question : When a person suffers from marked fall in B.P. it is helpful to administer him the following hormone

Question : When a person is injected with antiserum, the type of immunity developed is

Question : When a particular characteristic of an individual, e.g. petal colour, shows variation among the offspring produced after the indiviual is selfed, it is said to be

Question : When a neuron is in resting state, i.e., not conducting any impulse, the axonal membrane is :

Question : When a particle chromosome is present in three copies,the cell is a……………

Question : When a particular chromosome rejoins in reverse orientation ,mutation work in geneties.

Question : When a neural signal reaching the neuromuscular junction releases acetylcholine, an action potential is generated first in

Question : When a nerve fibres is stimulated the inside of the membrane becomes :

Question : When a mutation is limited to the substitution of one nucleotide for another , it is called :

Question : When a muscle bends one part upon the other, it is called

Question : When a microspore mother cell with 40 chromosomes undergoes meiosis each of the four resulting cell has(A) 80 chromosomes(B) 20 chromosomes(C) 10 chromosomes(D) 40 chromosomes

Question : When a man inhales air containing normal concentration of O_2 as well as CO he suffers from suffocation because