Botany and Plant Science

A single naked female flower is surrounded by five scorpioid cyme of male flowers in Cyathium. The inconspicuous male flowers occur in clusters and are reduced to a single red stamen, while the female flower consists of a single ovary (pistil) on a stalk (pedicel). Cyathium inflorescence shows the presence of achlamydeous flowers. 
Achlamydeous flowers are flowers without a perianth. The cyathia are sometimes solitary but are usually in cymes, inflorescences of the second order, in pseudumbels, on dichotomously branched stalks or in so-called simple cymes which consist of one central and two lateral cyathia. The showy, red, modified leaves of these plants are not petals. In fact, they are not even part of the true flowers. They surround clusters of small, greenish, cup-shaped structures called as cyathia. Each cyathium is actually a flower cluster or inflorescence containing unisexual, apetalous male and female flowers. 
Therefore, the correct answer is option B.

"Mono" means single so a monoecious plant is one that bears both male and female sex organs on same plant. The monoecious plant can produce bisexual flowers or unisexual flowers. A dioecious plant is one that bears both male and female sex organs on different plants. A dioecious plant will always produce unisexual flowers.

Rafflesia arnoldii makes the largest single flower in the Angiospermae. It is a parasitic plant. The flower weighs around 15 pounds and can grow up to the height of 3 ft.

A bisexual flower is a flower that contains all the four whorls such as petals, sepals, the male reproductive structure (stamen) and female reproductive structure (pistil). Hence it is also called as a complete or perfect flower. Thus the correct answer is 'Four whorls'.

Sunflower (Hellanthus annus ) is a inflorescence (capitulum) .It is a plant of family compositae (Asteraceae).  

Some plants never open to ensure complete selfpollination. This condition is called cleistogamy e.g., Commelina bengalensis , Oxalis, Viola, etc. The cleistogamous flower are bisexual small, inconspicuous, colourless and do not secrete nectar.

Anthesis is the specific biological term used to describe the period during which a flower is fully open and functional.

Apocarpous : Gynoecium consisting of two to many free carpels Each carple forms its own pistils, e.g.,  Ranunculus. 

In angiosperms flowers can be unisexual having either stamen or pistil; or bisexual having both stamen and pistil in same flower. In both the types of flowers, Pistil bears ovary. Fruit is ripened or matured ovary. After fertilisation ovary undergoes major changes and its wall also thickens to produce a fruit.

Hydrophilous (water-pollinated) flowers typically have pollen grains that are protected by a mucilaginous covering to prevent wetting, not dry pollen grains. Therefore, statement A is incorrect.

In pea and bean, five types of petals are present. The largest petal (standard) overlaps the two lateral petals (wings), which in turn overlap two smallest anterior petals, which are known as keel. 

Zygomorphic flowers that are bilaterally symmetrical so that they are able to be bisected into similar halves in only one plane, forming mirror images, e.g., Gladiolus flower.

Unisexual flowers have either the male reproductive part (stamens) or female reproductive part (pistil) but never both.
As the flowers contain either the stamen or pistil, the fertilization can take place when the pollen from another flower or plant comes near the pistil. As there will be fusion of male and female gametes from different individuals of the same species, it results in cross-fertilization.
When the ovary (female reproductive part) ripens, it forms the fruit. So, when a plant contains only stamen, female reproductive part, it cannot produce a fruit.
Thus, the correct answer is option (B).

Tetradynamous is a condition of androecium where six stamens are present of which four stamens are longer and are inserted in inner whorl and remaining two are smaller and are inserted in outer whorl. 
Cruciform corolla is a type of corolla containing four free petals arranged in the form of a cross. 
Solanum tuberosum flower contains five fused petals forming a infundibulum form corolla.
Abelmoschus esculentus and Ochroma lagopus belongs to family Malvaceae. Both contain five free petals. 
Brassica campestris flower possess four free petals forming a cruciform corolla (arranged in the form of a cross). 
Therefore, the correct answer is option D.

There are two clusters each with 3-9 flowers on a node in the axis of opposite leaf and each cluster has a condensed dichasial cyme ending in monochasial cyme and flowers have lever mechanism, it represents Verticillaster. A cymose inflorescence arranged in pairs at the nodes, in the manner of a false whorl, is called a verticillaster. A reduced raceme or cyme that grows in the axis of a bract is called a fascicle. A verticillaster is a fascicle with the structure of a dichasium; it is common among the Laminaceae. Many verticillasters with reduced bracts can form a spicate (spike-like) inflorescence that is commonly called a spike.