Class 11th| Botany Viva-Voce Question Answers

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Q1.What is a flower ? Why does it hold an important position in a plant?

Ans. Flower is a reproductive shoot of a plant, hence holds an important position.

Q2.Name the essential and non-essential whorls of a fower. Why are they so cailed

Ans. Androecium and Gynoecium are essential whorls, calyx and corolla are non-essentisl.

Q3.Give two examples each of a pedicellate and sessile flowers

Ans. Pedicellate-Mustard and pea; Sessile-Wheat and paddy

Q4.Match the given flowers with the corresponding features.

Flowers: (a) Petunia, (b) Pea, e) Onion
Features: (i) Complete, (ii) Zygomorphic, (iii) Gamopetalous

Ans(i) Onion, (ii) Pea, (iii) Petunia

Q5.What is perianth ? How does it differ from gamopetalous flowers ?

Ans.In perianth calyx and corolla cannot be distinguished. Gamopetalous fowers have oniy fused
petals.

Q6.Pea is a polypetalous whereas Petunia is a gamopetalous flower. What is the differenee
between their petals ?

Ans. Pea has free petals and Petunia has fused petals.

Q7. Name the flower which has 9+1 arrangement of stamens.

Ans.Pea.

Q8.What is syngenesious condition of stamens ? In which flower it is seen ?

Ans. Syngenesious stamens have fused anthers and free stamens. This is seen in sunflower.

Q9. In petunia flower the stamens are attached to the base of the petals or corolla tube.
What is this condition known as ?

Ans.Infundibulum

Q10.Gynoecium of onion is tricarpellary and syncarpous. Explain the statement.

Ans. Three pistils fused together.

Q11. The flower of pea is pentamerous and of mustard is tetramerous. What does it mean ?

Ans.Mustard has 4 petals, pea has 5 petals.

Q12. The ovary of pea flower is perigynous and of petunia is hypogynous. Which flower is
superior and why ?

Ans. Petunia ovary is superior as all the whorls arise from its base

Q13. What is a papillionacious corolla ?

Ans. It is corolla of pea family which possesses one large posterior standard, two lateral wings, two
innermost wings and a keel.

Q14.Why is it necessary to draw floral diagram besides floral formula to deseribe a flower?

Ans.Floral diagram explains aestivation of floral leaves, their relation with floral leaves and other
whorls, placentation in the ovary and position of floral whorls with respect to mother axis.
Floral formula cannot tell whether sepals are opposite to petals or alternate so floral diagram
is necessary.

Q15.Why is it easier to bring self-pollination in pea than in Onion ?

Ans.The corolla of sweet pea shows vexillary aestivation in which petals completely enclose
androecium and gynoecium and facilitate self-pollination. In onion flower the reproductive
whoris are exposed to environment so probability of cross-pollination increases.

Q16.What does mother axis represent in a floral diagramn?

Ans.Mother axis is the main axis bearing the flower. It is drawn with axial flower not the terminal
flower.

Q17.In a dorsifixed as well as versatile stamens the filaments are attached to the dorsal
side of the anther. What is the difference between the two ?

Ans.Dorsifixed anthers do not move free like versatile anthers.

Q18.How does a bract differ froma bracteole ?

Ans.Bract is a leaf like structure at the base of a flower. Brateole is a leaf like strudture On any
part of the flower stalk

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