Morphology of Flowering Plants Test 15

Corymb is a racemose inflorescence which have slightly shortened axis. Presence of longer pedicel in older flowers and shorter pedicels in younger flowers arrange the flowers at more or less at the same level. Umbel is racemose inflorescence with shortened main axis and presence of a whorl of bracts at tips. Flowers are arranged at the same level in centripetal order. Panicle is a branched raceme in which peduncle bears a number of branches in acropetal order carrying pedicellate flowers in acropetal succession. Monochasial cyme bears a terminal flower at the tip of main stem. A lateral branch is present below the terminal flower which itself ends in a flower. Repeat of this arrangement give a long coiled inflorescence (helicoid cyme). In scapigerous umbel, clusters of flowers develop on the tip which gives resemblance to umbel but it is scorpioid monochasial cyme in which axis is terminated in a terminal flower.
Therefore, the correct answer is option D.

A head (capitulum) is a short dense spike in which the flowers are borne directly on a broad, flat peduncle, giving the inflorescence the appearance of a single flower, as in the Dandelion (Taraxacum).
Capitulum inflorescence is present only in Compositae.
In Solanaceae inflorescence is Cymose. Gamopetalous corolla, epipetalous stamens and bicarpellary gynoecium are common in both Solanaceae and Compositae.
Therefore, the correct answer is option A.

Inflorescence is the arrangement of flower on the floral axis. There are two types of inflorescence as racemose and cymose. In racemose type, the main axis is unlimited in growth. It never terminates into a flower. There are many sub-types of racemose inflorescence. Head or capitulum also belongs to racemose type of inflorescence. It possess a flattened, convex main axis called as receptacle. This receptacle bears flowers in centripetal order. The whole inflorescence is surrounded by a whorl of bracts. 

Liliaceae flowers - Hermaphroditic, actinomorphic (radially symmetric) or slightly zygomorphic (bilaterally symmetric), pedicellate (on a short secondary stem), generally large and showy but may be inconspicuous (Medeoleae). Bracts may (bracteate) or may not (ebracteate) be present. The perianth is undifferentiated (perigonium) and biseriate (two whorled), formed from six tepals arranged into two separate whorls of three parts (trimerous) each, although Scoliopus has only three petals, free from the other parts, but overlapping. The tepals are usually petaloid (apotepalous) with lines (striate) or marks in other colors or shades. Malvaceae possess perianth of five coloured tepaIs. Solanaceae possess perianth of five coloured tepaIs joint together. possess perianth of six coloured tepaIs does not possess perianth of six coloured tepaIs. 
Therefore, the correct answer is option C.

The onion (Allium cepa L.) also known as the bulb onion or common onion, is used as a vegetable and is the most widely cultivated species of the genus Allium. The name wild onion is applied to a number of Allium species but A. cepa is exclusively known from cultivation and its ancestral wild original form is not known, although escapes from cultivation have become established in some regions. The onion is most frequently a biennial or a perennial plant, but is usually treated as an annual and harvested in its first growing season.
Allium cepa belongs to the family Liliaceae and not to Solanaceae, Cruciferae or Compositae. 
Therefore, the correct answer is option B.

Gramineae flower - Reproductive structures are distinct in that the inflorescences are made up of subinflorescences known as spikelets. The grass spikelet is defined by two basal sterile bracts or glumes. These subtend either a single (simple spikelet) or several (compound) florets.  The term floret, when applied to grasses, refers to the flower and two fertile bracts that usually enclose the flower, the lemma and palea. The perianth is reduced to vestigial structures, lodicules, positioned beneath the ovary and the fruit is single-seeded with the testa adnate to the pericarp, a caryopsis. In contrast to most large families, the fruit is usually not needed for species identification. So, the inflorescence of Gramineae is spikelet and not raceme, spike and thyrsus.
Therefore, the correct answer is option C.

Cucurbitaceae inflorescence - Axillary solitary or cymose or racemose, peduncle of male flower profusely branched while female solitary. The flowers are sympetalous and usually unisexual. In monoecious taxa the male flowers are often produced before the female ones, i.e. on more proximal parts of the shoots. Many taxa have single axillary female flowers and male flowers in lateral inflorescences at the same nodes, but several other arrangements exist.
Malvaceae - The flowers are commonly borne in definite or indefinite axillary inflorescences, which are often reduced to a single flower, but may also be cauliflorous, oppositifolious, or terminal. They often bear supernumerary bracts. They can be unisexual or bisexual, and are generally actinomorphic, often associated with conspicuous bracts, forming an epicalyx. Leguminosae and Cruciferae flowers are bisexual. 
Therefore, the correct answer is option C.

Flowers of Poaceae are characteristically arranged in spikelets, each spikelet having one or more florets. The spikelets are further grouped into panicles or spikes. A spikelet consists of two or sometimes fewer bracts at the base, called as glumes, followed by one or more florets. A floret consists of the flower surrounded by two bracts, one external the lemma and one internal the palea. The flowers are usually hermaphroditic maize being an important exception and anemophilous or wind-pollinated. The perianth is reduced to two scales, called as lodicules, that expand and contract to spread the lemma and palea. These are generally interpreted to be modified sepals. The lodicules are the two diminutive bodies lying between the lemma and the ovary base in the grass floret which, by expanding rapidly at the time of anthesis, lever away the rigid lemma allowing anthers and stigmas to emerge. Expansion results from the swelling of a cushion of tissue at the base of each lodicule.
Therefore, the correct answer is option A.

Flowers of Poaceae are characteristically arranged in spikelets, each spikelet having one or more florets. The spikelets are further grouped into panicles or spikes. A spikelet consists of two or sometimes fewer bracts at the base, called as glumes, followed by one or more florets. A floret consists of the flower surrounded by two bracts, one external the lemma and one internal the palea. The flowers are usually hermaphroditic maize being an important exception and anemophilous or wind-pollinated. The perianth is reduced to two scales, called as lodicules, that expand and contract to spread the lemma and palea. These are generally interpreted to be modified sepals. The lodicules are the two diminutive bodies lying between the lemma and the ovary base in the grass floret which, by expanding rapidly at the time of anthesis, lever away the rigid lemma allowing anthers and stigmas to emerge. Expansion results from the swelling of a cushion of tissue at the base of each lodicule. Perianth of Gramineae are not termed as tepal, ligule and spur. 
Therefore, the correct answer is option C.