TamilNadu Class 12th Botany Exam 2023 : 1 Marks Important Question with Solution

TamilNadu Class 12th Botany Exam 2023 : 1 Marks Important Question with Solution

Botany is one of the important subjects for those who want to pursue a career as a botanist. TN Board Class 12 Botany Important Questions are a valuable resource for revision purpose.

It boosts their confidence and can also self-analyze their preparation level so that they don't miss any topic from the syllabus. Students can solve these TN Board Class 12 Botany important questions for practice.

1 Mark Questions

Q.1. Which of the following part in a flower is diploid?

(a) Pollen grain

(b) Egg

(c) PEN

(d) Secondary nucleus

Q.2. In some seeds the nucellus may be persistent. Such nucellus is called…………..

Ans. Perisperm

Q.3. Observe the relationship between the first two terms and fill in the blank.

a. Overy wall : Pericarp Integuments : --------------------

Ans. Protective envelope of ovule

b. 2 celled pollengrain :- vegetative cell +generative cell 3 celled pollengrain :- vegetative cell +……………………..

Ans. 2 male gametes

Q.4. Development of fruit without fertilization and are seedless known as

a) Polyembryony

b) Apomixis

c) Parthenocarpy

d) Parthenogenesis

Q.5. ------------- is the proteinaceous layer which separate endosperm & embryo in a monocot seed

Ans. Aleurone layer

Q.6. Observe the relationship between the first pair and fill in the blanks.

a. Perisperm :- Remnants of nucellus ------------: - Fruit wall

Ans. Pericarp

b. Parthenocarpy : Formation of fruit without fertilization Apomixis : ---------------------

Ans. Formation of seeds without fertilization

Q.7. In maize, the chromosome number present in the meiocyte is 20. Give the number of chromosomes present in the following.

a. Maize pollen

Ans. 10

b. Maize endosperm

Ans. 30

Q.8. After syngamy & triple fusion in embryo sac, embryo will be diploid and endosperm will be………..

Ans. Triploid / 3n

Q.9. Innermost wall layer of microsporangium which nourishes the pollengrain is called-------------

Ans. Tapetum

Q.10. Fruit which develop from any part of the flower other than ovary is called……………..

Ans. False fruit

Q.11. A date palm seed discovered during archeological investigation retained viability even after 10000years. The retention of viability is due to the state of inactivity of embryo is called…………..

Ans. Dormancy

Q.12. Which among the following is a parthenocarpic fruit? ( Banana , Apple , Strawberry , Guava)

Ans. Banana

Q.13. From the following, select the two having haploid chromosome number (Egg, Endosperm, Zygote, Pollen)

Ans. Egg & Pollen

Q.14. In albuminous seed, food is stored in ------------

Ans. Endosperm

Q.15. In the Coconut fruit, the coconut water is ………………

Ans. Liquid endosperm

Q.16. Observe the relationship between the first pair and fill in the blanks.

Epicotyl :- Embryonal axis above the level of cotyledon ………….. :- Cylindrical portion below the level of cotyledon

Ans. Hypocotyl

Q.17. Formation of more than one embryo in the seed is called……………

Ans. Polyembryony

Q.18. Animal visitors which consume pollengrains or nector without bringing about pollination are called………………

Ans. Pollen robbers

Q.19. Observe the relationship between the first pair and fill in the blanks Pollen viability :- The period for which pollen grains remain fuctional ………………… :- Storage of pollengrains for years in liquid nitrogen (-196°C)

Ans. Pollen bank

Q.20. Most resistant organic material on exine of pollengrains

(a) Sporopollenin

(b) Cellulose

(c) Chitin

(d) Pectin

Q.21. Name two plants where remnants of nucellus can be found in the seed.

Ans. Black pepper and Beet

Q.22. In rDNA technology, Precipitated DNA threads can be removed by ……………….

Ans. Spooling

Q.23. Which of the enzymes removes nucleotides from the ends of a DNA?

(a) Exonuclease

(b) Endonuclease

(c) DNA ligase

(d) DNA polymerase

Q.24. What is the principle of PCR?

Ans. Amplification of genetic material

Q.25. Who constructed the first rDNA?

Ans. Stanly Cohen & Herbert Boyer

Q.26. In Gel electrophoresis, separated DNA fragments can be visualized after staining. Name the stain used for it.

Ans. Ethidium bromide

Q.27. DNA fragments with same kind of sticky ends can be joined by

(a) Ligase

(b) Endonuclease

(c) Exonuclease

(d) polymerase

Q.28. The first restriction endonuclease isolated is………….

Ans. Hind ΙΙ

Q.29. The restriction enzyme EcoRΙ is isolated from the bacterium…………..

Ans. Escherichia coli RY 13

Q.30. Ti plasmid used in genetic engineering is obtained from…………….

Ans. Agrobacterium tumefaciens

Q.31. Name the process through which a piece of DNA is introduced into host bacterium

Ans. Transformation

Q.32. Identify the substance used as a matrix in Gel electrophoresis

Ans. Agarose gel

Q.33. Name the specific base sequence in the DNA , which is recognised by particular restriction endonuclease

Ans. Recognition sequence

Q.34. Small chemically synthesized oligonucleotides that are complementary to the template DNA are called …………..

Ans. Primers

Q.35. Name two commonly used vectors for genetic engineering

Ans. Plasmids & bacteriophages

Q.36. Self replicating extra chromosomal circular DNA present in prokaryoytic cells are called………..

Ans. Plasmid

Q.37. Name the enyme used for the digestion of bacterial cell wall

Ans. Lysozyme

Q.38. Name the enzyme used for the digestion of fungal cell wall

Ans. Chitinase

Q.39. Which gene is used as an alternative selectable marker?

Ans. Gene for β galactosidase enzyme

Q.40. protein formed in a heterologous host is called………….

Ans. Recombinant protein

Q.41. Name the first transgenic cow that produce human protein enriched milk

Ans. Rosie

Q.42. Name the gene that control corn borer insect?

a. cry Ι Ac

b. cry ΙΙ Ab

c. cry Ι Ab

d. cry ΙΙ Ac

Q.43. What does Bt stands for in Bt cotton?

Ans. Bacillus thuringiensis

Q.44. Name the nematode which infects the roots of tobacco plants , resulting in the reduction of yield?

Ans. Meloidegyne incognitia

Q.45. Clones with radioactivity can be detected by

(a) Gel electrophoresis

(b) Autoradiography

(c) Chromatography

(d) ELISA

Q.46. Insulin consists of two short polypeptide chains A and B and the two chains are joined by

(a) Peptide bond

(b) Disulphide bond

(c) Hydrogen bond

(d) Ionic bond

Q.47. Name two gens that control cotton bollworms

Ans. cryIAc & cryIIAb

Q.48. Which company prepared genetically engineered human insulin ?

Ans. Eli Lilly

Q.49. In which year first clinical gene therapy was performed and to whom ?

Ans. 1990

Q.50. Expand ADA

Ans. Adenosine Deaminase

Q.51. Name the toxic protein produced by Bacillus thuringiensis?

Ans. Cry protein /Bt toxin

Q.52. Name a Bioinsecticide

Ans. Bt Cotton

Q.53. Name a genetically modified pest resistant crop

Ans. Tobacco

Q.54. Name the interaction in which both the interacting species are benefited

Ans. Mutualism

Q.55. Name the relationship between an orchid plant and a mango tree

Ans. Commensalism

Q.56. Name the interaction in which one organism captures and feeds on another

Ans. Predation

Q.57. Name the Interaction between two organism for same resource.

Ans. Competition

Q.58. A mechanism that promote co-existance rather than exclusion is…………..

Ans. Resource partitioning

Q.59. Name the interaction in which one species is harmed and the other is neither benefited nor harmed.

Ans. Ammensalism

Q.60. Relative measure of reproductive success of an organism is called…………..

Ans. Darwinian fitness

Q.61. Number of individuals present per unit area at a given time is called…………

Ans. Population density

Q.62. The size of a population is not static. Which of the following leads to increase in population?

(a) Natality & Mortality

(b) Mortality & Emigration

(c)Mortality & Immigration

(d) Natality & Immigration

Q.63. Observe the relationship between the first two terms anf fill in the blanks.

a. Mycorrhiza :- Mutualism Lice on humans :- …………….

Ans. Parasitism

b. Mortality :- No of death in the population during a given period …………..:- No of births in the population during a given period

Ans. Natality

Q.64. The feeding efficiency of one species is reduced due to the interfering & inhibitory presence of the other species even if resources are abundant is …………….

Ans. Interference competition

1. Natural interlinked food chains are called……………

Ans. Food web

Q.65. Which of the following is a detritivore?

(a) Earthworm

(b) Virus

(c) Lion

(d) Deer

Q.66. Detritus food chain begins with…………

Ans. Detritus / Dead remains

Q.67. What is the percentage of photosynthetically active radiation (PAR) in the incident solar radiation?

(a) 100%

(b) 20 %

(c) 39%

(d) 50%

Q.68. Vertical distribution of different species occupying different levels in an ecosystem is called…………..

Ans. Stratification

Q.69. Total biomass of living organisms at a particular time in a given ecosystem is called…………

Ans. Standing crop

Q.70. Organism which breakdown detritus is called……………

Ans. Decomposer / Detritivore

Q.71. Dead remains of plants and animals are called…………….

Ans. Detritus

Q.72. Annual NPP of biosphere is …………..

Ans. 170 billion tons

Q.73. Linear sequence of energy transfer in an ecosystem by eating and being eaten is called………..

Ans. Food chain

Q.74. Insects which are feeding on plant saps are called…………..

Ans. Phytophagous insects

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