CBSE Questions for Class 11 Medical Biology Morphology Of Flowering Plants Quiz 17 - MCQExams.com

The inflorescence in the Bougainvillea flower is a simple cyme or cymule. In the cymule, the peduncle ends in a flower and only 2 lateral branches. These are produced which also ends in flowers. Thus, 3 flowered inflorescences will be formed. Flowers are arranged in a basipetal manner. Since the inflorescence number will be given here 34. Thus, the total numbers of flowers would be $$34 \times 3 = 102.$$

Single female flower-like inflorescence of the Euphorbiaceae i.e. Poinsettia is called a cyathium. The single female flower of cyathium has 3 carpels syncarpous pistil. Also, the inflorescence number given here is 42. Thus hence the number of female flowers is 42.

So, the correct answer will be 102,42.

The correct option is C.

In the bud stage, the inner floral parts are covered with the outer whorl of calyx made up of sepals. When the bud opens, the sepals remain at the base at protection.

A. The whorl of petals called corolla form the next whorl after sepals. It protects the androecium and gynoecium and also attracts pollinators.

B. Anthers are the parts of stamens that produce microspores or pollen grains.

C. Sepals cover the floral bud.

D. Stigmas are the parts of carpel that receive the pollen grains.

Hence, the correct answer is 'Sepals'

$$\textbf{Correct option: B}$$

$$\textbf{Solution:}$$

$$\textbf{Explanation for correct option:}$$

Option B:

$$\bullet$$ Flower is a modified shoot.

$$\bullet$$ The floral components, calyx, corolla, androecium, and gynoecium, are basically the modified parts of a normal shoot.

$$\bullet$$ These modifications and initiated by the hormonal changes occur in the plant.

$$\textbf{Explanation for incorrect options:}$$

Option A:

$$\bullet$$ Placentation is the arrangement of placentas of the ovules inside an ovary.

$$\bullet$$ Primrose exhibits the free central type of placentation and not the basal.

$$\bullet$$ The free central placentation looks like the axile placentation but there are no locules present in it because the ovary is not partitioned as septa are absent.

$$\bullet$$ In basal placentation, one or more ovules are directly attached to the base of the ovary such as in Marigold, Sunflower, etc.

Option C:

$$\bullet$$ Tomato is not a capsule, it is a berry fruit.

$$\bullet$$ Capsule fruit is a simple and dry fruit having more than one pistils which split or dehisce at maturity to release seeds present inside it.

$$\bullet$$ Berry fruit is a simple fruit having many seeds arranged within the pulp of the fruit.

Option D:

$$\bullet$$ Orchids are the flowering plants whose seeds do not possess endosperm.

Hence the correct option is option B.

Pisum commonly known as a pea is a genus of flowering plant belonging to family Fabaceae. In Fabaceae, the flowers are zygomorphic (bilateral symmetry), bisexual. The petals 5, polypetalous, the posterior outermost petal is large (the vexillum or standard), two lateral petals (the wings or alae) and the two anterior and innermost petals are united to form a boat-shaped structure (the keel or carina), descending imbricate or vexillary aestivation. Stamens are 10, diadelphous (stamens united by their filaments so as to form two groups). Placentation is marginal (placenta forms a rigid along ventral side and ovules are arranged in two vertical rows). So, the correct answer is 'Pisum'.

• An inflorescence is a group or cluster of flowers arranged on a stem that is composed of the main branch or a complicated arrangement of branches. 
• Cyme is an arrangement of flower cluster with a central stem bearing a single terminal flower that develops first and the other flowers in the cluster developing as terminal buds of lateral stems. 
• A dichasial cyme is a determinate inflorescence in which the growth of the central axis is terminated by a flower that opens first and each pair of branches subtending this flower then is terminated by a single flower.
  
• In Jasmine flower, the flowers are borne in cymose clusters with a minimum of three flowers, though they can also be solitary on the ends of branchlets (i.e. shows dichasial cyme).

A.     Correct option: B

B.    Explanation for correct option:

This is the type of racemose inflorescence found in mustard, wheat etc

• In acropetal succession, the position of youngest flower is distal or towards apex
• The position of older flowers is proximal or towards the base.

• In grasses and many monocots, the leaf base is broad and surrounds the stem as an envelope, such a leaf base is called sheathing leaf base. e.g., Sorghum, Wheat, and Palms. Hence statement (A) is a correct statement.
•  The leaf is attached to the stem by the leaf base. In some leguminous plants, the leaf-base may become swollen, which is called the pulvinus. Hence statement (B) is a correct statement.
•  Phyllotaxy is the pattern of arrangement of leaves on the stem or branch. In Alstonia, more than two leaves arise at a node and form a whorl. Hence Whorled phyllotaxy is found in Alstonia. Hence statement (E) is a correct statement.
• Hence Three statements are correct i.e (A),(B) AND (E).
• So, the correct answer is 'Three'.

Solution:

Correct answer is option A.

Explanation for correct option:

• Inflorescence in Solanaceae family is solitary axillary, umbellate cyme, or helicoid cyme in Solanum.
• Determinate simple inflorescences are generally called as cymose. The main kind of cymose inflorescence is the cyme.
• Inflorescence meristem terminates into a floral bud, followed by the next floral meristem forming on the flank of the previous flower.