CBSE Class 12 Biology Strategies for Enhancement in Food Production Assignment Set B

 

Question. Biological principles as applied to animal husbandry and food production. Which of the following technique is not going to play a pivotal role in further enhancing food production
(a) Embryo transfer technique
(b) Tissue culture technique
(c) Mutations
(d) Biomining

Answer : D

Question. Green revolution was dependent to a large extent on plant breeding techniques for development of
(a) High yielding varieties
(b) Disease resistant varieties
(c) Wild varieties
(d) Both 1 and 2

Answer : D

Question. Purposeful manipulation of plant species in order to create desired plant type that are better suited for cultivation, give better yields and disease resistant is
(a) Plant systematics
(b) Plant breeding
(c) Plant monitoring
(d) Biofortification

Answer : B 

Question. Which of the following is root of any plant breeding programme
(a) Genetic variability
(b) Evaluation and selection of parents
(c) Cross hybridisation among selectied parents
(d) Selection of superior recombinants

Answer : A

Question. Production of thousands of plants through tissue culture method is called :
(a) Macropropagation
(b) Micropropagation
(c) Somatic embryo
(d) Totipotency

Answer : B

Question : Crop plants grown in monoculture are
(a) highly prone to pests
(b) low in yield
(c) free from intraspecific competition
(d) characterised by poor root system. 

Answer : A

Question : In maize, hybrid vigour is exploited by
(a) inducing mutations
(b) bombarding the protoplast with DNA
(c) crossing of two inbred parental lines
(d) harvesting seeds from the most productive plants. 

Answer : C

Question : Triticale, the first man-made cereal crop, has been obtained by crossing wheat with
(a) barley
(b) rye
(c) pearl millet
(d) sugarcane. 

Answer : B

Question : Three crops that contribute maximum to global food grain production are
(a) wheat, rice and maize
(b) wheat, rice and barley
(c) wheat, maize and sorghum
(d) rice, maize and sorghum. 

Answer : A

Question : Which of the following is generally used for induced mutagenesis in crop plants?
(a) X-rays
(b) UV (260 nm)
(c) Gamma rays (from cobalt-60)
(d) Alpha particles 

Answer : C

Question : The name of Norman Borlaug is associated with
(a) white revolution
(b) green revolution
(c) yellow revolution
(d) blue revolution.

Answer : B

Question : India’s wheat yield revolution in the 1960s was possible primarily due to
(a) hybrid seeds
(b) increased chlorophyll content
(c) mutations resulting in plant height reduction
(d) quantitative trait mutations.

Answer : D

Question : When a diploid female plant is crossed with a tetraploid male, the ploidy of endosperm cells in the resulting seed is
(a) tetraploidy
(b) pentaploidy
(c) diploidy
(d) triploidy. 

Answer : A

Question : If a diploid cell is treated with colchicine then it becomes
(a) triploid
(b) tetraploid
(c) diploid
(d) monoploid. 

Answer : B

Question : Which of the following crops have been brought to India from New world?
(a) Cashewnut, potato, rubber
(b) Mango, tea
(c) Tea, rubber, mango
(d) Coffee

Answer : A

Question : Before the European invader which vegetable was absent in India?
(a) Potato and tomato
(b) Shimla mirch and brinjal
(c) Maize and chichinda
(d) Bitter gourd 

Answer : A

Question : Triticale is obtained by crossing wheat with
(a) oat
(b) barley
(c) maize
(d) rye. 

Answer : D

Question : The new varieties of plants are produced by
(a) introduction and mutation
(b) selection and introduction
(c) selection and hybridization
(d) mutation and selection. 

Answer : C

Question : The reason for vegetatively reproducing crop plants to suit for maintaining hybrid vigour is that
(a) they are more resistant to diseases
(b) once a desired hybrid produced, no chances of losing it
(c) they can be easily propagated
(d) they have a longer life span. 

Answer : B

Question : If an angiospermic male plant is diploid and female plant tetraploid, the ploidy level of endosperm will be
(a) tetraploid
(b) pentaploid
(c) haploid
(d) triploid. 

Answer : B

Question : Which of the following is the New World spice, that has become an essential part of Indian cuisine?
(a) Red pepper
 (b) Black pepper
(c) Ginger
(d) Cardamom 

Answer : A

Question : Haploid plants can be obtained by culturing
(a) pollen grains
(b) root tips
(c) young leaves
(d) endosperm. 

Answer : A

Question : Haploid plants are preferred over diploids for mutation study because in haploids
(a) recessive mutation express immediately
(b) induction of mutations is easier
(c) culturing is easier
(d) dominant mutation express immediately.

Answer : A

Question : Which crop variety is not due to induced mutations?
(a) Reimei of rice
(b) Prabhat of arhar
(c) Sharbati Sonora of wheat
(d) Aruna of castor 

Answer : D

- It is the scientific agricultural practice of breeding and raising livestock.

- It deals with the care & breeding of livestock (buffaloes, cows, pigs, horses, cattle, sheep, camels, goats etc.), poultry farming and fisheries.

- More than 70% of the world livestock population is in India & China. However, the contribution to the world farm produce is only 25%, i.e., the productivity per unit is very low. Hence new technologies should be applied to achieve improvement in quality and productivity.

- It is the management of animals for increasing yield and quality of milk and its products.

- Milk yield depends on the quality of breeds in the farm.

- It is important to select good breeds having high yielding potential and resistance to diseases.

- Ways for the yield potential:

¶ Look after the cattle (housing well, give adequate water and maintain disease free).

¶ Feeding of cattle in a scientific manner – emphasis on the quality and quantity of fodder.

¶ Stringent cleanliness and hygiene of cattle & handlers while milking, storage and transport of the milk.

- Nowadays, these processes have mechanized. It reduces chance of direct contact of the produce with the handler.

- To ensure these stringent measures there should be

¶ Regular inspections to identify and rectify problems.

¶ Regular visits by a veterinary doctor.

- Poultry is the domesticated birds used for food or eggs.

E.g. chicken, ducks, turkey and geese.

- Components of poultry farm management:

¶ Selection of disease free and suitable breeds.

¶ Proper and safe farm conditions.

¶ Proper feed and water.

¶ Hygiene and health care.

 

- A breed is a group of organisms related by descent and similar general appearance, features, size etc.

- Breeding is the modification of genotype of an organism to make that organism more useful to humans. E.g. Jersey (improved cattle breed), Leghorn (improved chicken breed).

- Animal breeding aims at increasing the yield of animals and improving the desirable qualities of the produce.

- Breeding is 2 types: Inbreeding and out-breeding.

 

It is the mating of more closely related individuals within the same breed for 4-6 generations. This strategy is as follows:

¶ Identify and mate superior males & females of same breed.

¶ Evaluate the progeny obtained and identify superior males and females among them for further mating.

In cattle, a superior female produces more milk per lactation. A superior male (bull) gives rise to superior progeny.

 

¶ It increases homozygosity to evolve a pure line animal.

¶ It exposes harmful recessive genes that are eliminated by selection.

¶ It helps in accumulation of superior genes and elimination of less desirable genes. This increases the productivity of inbred population.

Continued inbreeding, especially close inbreeding, may reduce fertility and productivity. This is called inbreeding depression. To solve this problem, selected animals should be mated with unrelated superior animals of the same breed.

It is the breeding of the unrelated animals. It includes out- crossing, cross-breeding and inter-specific hybridization.

- It is the mating of animals within the same breed, but having no common ancestors on either side of their pedigree up to 4-6 generations.

- The offspring of such a mating is known as out-cross.

- It is the best method for animals having low milk productivity, growth rate in beef cattle, etc.

- It helps to overcome inbreeding depression.

- It is the mating of superior males of one breed with superior females of another breed.

- The desirable qualities of 2 different breeds are combined.

- The progeny hybrid animals may be used for commercial production or may be subjected to inbreeding and selection to develop new stable superior breeds.

- E.g. Hisardale (sheep) developed in Punjab by crossing

Bikaneri ewes and Merino rams.

- It is the mating of male and female of two different species.

- In some cases, the progeny may combine desirable features of both the parents, and may be of considerable economic value. E.g. Mule (male ass X female horse).

 

- The semen collected from male parent is injected into the reproductive tract of selected female by the breeder.

- Semen is used immediately or is frozen and used later. Frozen semen can also be transported.

- Success rate of crossing mature male & female is low even though artificial insemination is carried out.

- It is a programme for herd improvement. It improves chances of successful production of hybrids.

- In this, a cow is administered hormones such as FSH to induce follicular maturation & super ovulation (production of 6-8 eggs per cycle instead of one egg).

- The animal is either mated with an elite bull or artificially inseminated. Fertilised eggs at 8–32 cells stage are recovered non-surgically and transferred to surrogate mothers.

- MOET has been demonstrated for cattle, sheep, rabbits, buffaloes, mares, etc.

- High milk yielding breeds of females and high quality (lean meat with less lipid) meat-yielding bulls have been bred successfully to increase herd size in a short time.

- It is the maintenance of hives of honeybees to produce honey and beeswax.

- Most common species that can be reared is Apis indica.

- Honey is a food of high nutritive and medicinal value.

- Beeswax is used in preparation of cosmetics, polishes etc.

- Apiculture can be practiced in an area having bee pastures of some wild shrubs, fruit orchards and cultivated crops.

- Important points for successful bee-keeping:

(i) Knowledge of the nature and habits of bees.

(ii) Selection of suitable location for keeping beehives.

(iii) Catching and hiving of swarms (group of bees).

(iv) Management of beehives during different seasons.

(v) Handling and collection of honey and beeswax.

- Bees are the pollinators of crop species such as sunflower, Brassica, apple and pear.

- Keeping beehives in crop fields during flowering period increases pollination. It improves crop and honey yield.

 

- Fishery is an industry of catching, processing or selling of fish, shellfish or other aquatic animals (prawn, crab, lobster, edible oyster etc.).

- Freshwater fishes: Catla, Rohu, common carp etc.

Marine fishes: Hilsa, Sardines, Mackerel, Pomfrets etc.

- Fisheries provide income and employment to millions of fishermen and farmers.

- Aquaculture (farming of aquatic organisms) & pisciculture (farming of fishes) are the techniques to increase the production of aquatic plants and animals.

- Blue Revolution: The development and flourishing of the fishery industry.

 

- Nobel laureate Norman E. Borlaug (International Centre for Wheat & Maize Improvement, Mexico) developed semi-dwarf wheat.

- In 1963, high yielding and disease resistant wheat varieties like Sonalika & Kalyan Sona were introduced in India.

- Semi-dwarf rice varieties were derived from IR-8, (developed at International Rice Research Institute (IRRI), Philippines) and Taichung Native-1 (from Taiwan). Later better-yielding semi dwarf varieties Jaya and Ratna were developed in India.

Sugar cane: Saccharum barberi (grown in north India, but poor sugar content & yield) was crossed with Saccharum officinarum (tropical canes in south India, thicker stems and higher sugar content but do not grow well in north India) and got a hybrid sugar cane having desirable qualities like high yield, thick stems, high sugar and ability to grow in north India.

Millets: Hybrid maize, jowar & bajra developed in India. It includes high yielding varieties resistant to water stress.

 

- Plant diseases cause crop losses up to 20-30% or even total.

- Disease-resistant cultivars enhance food production and helps to reduce the use of fungicides and bactericides.

- Resistance of the host plant is the genetic ability to prevent the pathogens from disease.

¶ Fungal: Rusts. E.g. brown rust of wheat, red rot of sugarcane and late blight of potato.

¶ Bacterial: Black rot of crucifers.

¶ Viral: Tobacco mosaic, turnip mosaic, etc.

 

¶ Screening germplasm for resistance sources.

¶ Hybridisation of selected parents.

¶ Selection and evaluation of the hybrids.

¶ Testing and release of new varieties.