Class 11th | Botany Viva-Voce Question Answers

Q1. Define the term "inflorescence."

Ans. It is "the reproductive shoot bearing number of flowers.

Q2.How are the flowers arranged in racemose and cymose inflorescence ? Explain.

Ans. In racemose, the flowers are axillary in position arranged in acropetal manner. T'hese are never borne on tip of the shoot. In cymose, the flowers are stalked, arranged in basipetal order and are always borne on tip of the shoot.

Q3. Give seven types of racemose inflorescence with one example each.

Ans. (i)Raceme-radish, (ii) Spike-amaranth, (iii) Catkin-mulberry, (iv) Spadix-banana, (v)Corymb-candituft, (vi) Umbel-coriander, (vii) Capitulum-sunflower.

Q4. Classify the following on the basis of type of inflorescence : (a) Mulberry, (b) Ficus

(c) Coriander, (d) Jasmine, (e) Calotropis, (f) Banana, (g) Mustard.

Ans. (a) Catkin (b) Hypanthodium, (c) Umbel, (d) Dichasial cyme, (e) Polychasial cyme, (f) Spadix,(g) Racemne.

Q5.State one differenee between a Spike and a Raceme.

Ans. In Raceme, flower are stalked in spike they are without sallk.

Q6.Define the following : (a) Involucre, (b) Períanth, (c) Florets

Ans. (a) A whorl of bracts, (b) Flowers in which calyx and corolla caannot be distinguishd (c)unisexual flowers.

Q7. Differentiate between the following: (i) Scorpoid and helicoid cyme, (ii) Dichasial and polychasial cyme, (iii) Acropetal and basipetal arrangement.

Ans. (i)Scorpoid cyme -The lateral branches with fiower on the tip are alternate.

Helicoid cyme-The lateral branches with flower on the tip are on the same side of bearing flower at the tip arise.

(ii) Diachasial type-The main axis bears flowers and from its base two lateral branches bearing flower at the tip arise.

Polychasial cyme- From the base of terminal flower more tnan two lateral branches arise each bearing flower at the tip

(iii) Acropetal flowers-New flowers are borne above the old ones on the shoot.

Basipetal flowers-The new flowers are borne lower to the old fowers.

Q8. Explain the following: (a) Verticillaster; (b) Hypanthodium inflorescence.

Ans. (a) Verticillaster: There are two clusters of sessile flowers arising from the axil of the two opposite leaves. That is the first axis terminates in a flowers and below this 2 alternate branches  cluster  of sessile flowers .e.g. Scared basil (Ocimum sanctum).

(b) Hypanthodium: Main axil takes shape of a cup with a small opening at the top.The male and female flowers are separate represented by pistil and stamens respectively. These flowers are arranged in cymose pattern. e,g Ficus.

Q9. State one feature which will help you to identify the inflorescence as Raceme ,Cymose or Special type.

Ans. (i) Racemose: Flower is never terminal. (i) Cymose: Flower is terminal in position.

(iii) Special type : Flower is in special structure and position

Q10. The students were amazed when the teacher told that sunflower and merigold are bouquet not mearly single flowers, What explanation the teacher wouid have given for her statement ?

Ans. Each floret of a sunflower or merigold is a flower. Hence  flower is a bunch of tiny flower and so can be called a bouquet.

Q11. Spike and catkin both are racemose type of inflorescenee with sessile fiowers

what is the difference between them ?

Ans. The catkin has several sessile flowers around axis that gives it a pendulous sape.

Q. 12. Hypanthodium and cyathium both have separate female fowers.What is the

difference between their flowers ?

Ans. The cyathium has only one female flower but the hypanthodium has several such flowers.