Free Plant Breeding and Genetics MCQs with Answers

• A. Oat
• B. Rice
• C. Barley
• D. Wheat

Explanation: Norin 10 is a Japanese dwarf wheat variety that donated important reduced-height genes used in modern wheat breeding.

• A. Donald (1968)Access Government Careers
• B. Finlay (1968)
• C. Rasmesson (1987)
• D. Jennings (1958)

Explanation: The term ideotype was coined by C. M. Donald in 1968 for an ideal plant type designed to achieve a specified production goal.

• A. Oat
• B. Linseed
• C. Gram
• D. Tomato

Explanation: Flor developed the gene-for-gene concept while studying flax resistance to flax rust.

• A. Lethal mutation
• B. Sub-vital mutation
• C. Vital mutation
• D. Sub lethal mutation

Explanation: A sublethal mutation kills about half of the individuals carrying it, whereas a fully lethal mutation kills all carriers under the…

• A. Barley
• B. Maize
• C. Wheat
• D. Oat

Explanation: Stadler pioneered the use of X-rays to induce mutations in barley, helping establish mutation breeding as a practical breeding method.

• A. Isochromosome
• B. Normal chromosome
• C. Traits located chromosome
• D. None of the aboveAccess Government Careers

Explanation: A primary trisomic carries one additional complete, normal chromosome, giving a chromosome number of 2n+1.

• A. Anenploidy
• B. Trisomy
• C. Euploidy
• D. all the above

Explanation: Euploidy is a chromosome-number change involving complete sets of chromosomes, such as haploidy or polyploidy.

• A. 2n-2
• B. 2n+1
• C. 2n-1
• D. 2n+2

Explanation: Nullisomy means that both copies of one homologous chromosome are missing, so its formula is 2n−2.

• A. Apomixis
• B. All the above
• C. Asexual reproduction
• D. Polyploidy

Explanation: Heterosis can be maintained across generations through apomixis or other asexual reproduction, while polyploidy may also help preserve…

• A. Composites
• B. Multi lines
• C. Hybrids
• D. Synthetics

Explanation: Hybrids are produced by crossing selected inbred or genetically distinct parents, so they express heterosis directly in the F1 generation.

• A. Simmonds (1979)
• B. East (1908)
• C. Davenport (1908)
• D. Davis (1927)

Explanation: Davis proposed the top-cross method in 1927 to evaluate the combining ability of inbred lines by crossing them with a common tester.

• A. Richey (1914)
• B. Meredith and Bridge (1972)
• C. Jenkins (1935)
• D. Hull (1950)

Explanation: Meredith and Bridge used the term useful heterosis in 1972 for hybrid superiority that has practical value in crop production.

• A. Proline
• B. Opaque 2
• C. Gang as
• D. African tall

Explanation: The opaque-2 mutant in maize increases the proportion of lysine and improves the grain's protein quality.

• A. Threonine
• B. Lysine
• C. Methionine
• D. a and b

Explanation: Lysine is commonly the first limiting amino acid in cereal grains, while threonine is also nutritionally limiting in many cereal-based…

• A. Nucleus
• B. Chloroplast
• C. Cutoplasm
• D. Vacuole

Explanation: A vacuole is enclosed by the tonoplast, a selectively permeable membrane that regulates exchange between the vacuolar sap and cytoplasm.

• A. Plasma membrane
• B. Cellulose cell wall
• C. Nuclear membrane
• D. Epidermis

Explanation: The cellulose cell wall forms the outermost boundary of a plant cell and lies outside the plasma membrane.

• A. 2000 times
• B. 4000 times
• C. 400,000 times
• D. 200,000 times

Explanation: Traditional biology texts commonly give about 200,000 times as the maximum magnification of an electron microscope, far above the limit of…

• A. Peroxisome
• B. Spherosome
• C. Lysosome
• D. Ribosome

Explanation: Ribosomes are the smallest cell organelles, generally about 20–30 nm in diameter, and they carry out protein synthesis.

• A. Segregation of the products of sunthesis
• B. Protein synthesis
• C. Photosynthesis
• D. RNA synthesis

Explanation: “Gorge bodies” refers to Golgi bodies, which modify, package and segregate materials produced in the cell, especially secretory products.

• A. Cowdry
• B. Altmann
• C. Palade
• D. Garner

Explanation: George Emil Palade discovered ribosomes using electron microscopy and studied their role in protein synthesis.