Do you know what is a strawberry?
By Tulipa_negra
@Tulipa_negra (383)
Portugal
December 4, 2006 8:31am CST
its my favourite fruit...yumiiiii....
The strawberry (Fragaria) is a genus of plants in the family Rosaceae, and the fruit of these plants. There are more than 20 named species and many hybrids and cultivars. The most common strawberries grown commercially are cultivars of the Garden strawberry, Fragaria × ananassa. Strawberries are a valuable source of vitamin C. See Garden Strawberry for information about the fruit as a food.
Morphology
Closeup of the surface of a strawberry
Strawberry flowers and developing fruitThe strawberry is an accessory fruit; that is, the fleshy part is derived not from the ovaries (which are the "seeds", actually achenes) but from the peg at the bottom of the hypanthium that held the ovaries. So from a technical standpoint, the seeds are the actual fruits of the plant, and the flesh of the strawberry is modified receptacle tissue. It is greenish-white as it develops and in most species turns red when ripe.
The rosette growth of the plants are a well-known characteristic. Most species send out long slender runners that produce a new bud and roots at the extremity, allowing the plant to spread vegetatively. The leaves typically have three leaflets, but the number of leaflets may be five or one.
While the flower has the typical rosaceous structure, the fruit is very peculiar, but it may be understood by the contrast it presents with the rose hip of the rose. In a rose the top of the flower-stalk expands as it grows into a vase-shaped cavity, the hip, within which are concealed the true fruits or seed-vessels. In the rose the extremity of the floral axis is concave and bears the carpels in its interior. In the strawberry, the receptacle (floral axis), instead of being concave, swells out into a fleshy, dome-shaped or flattened mass in which the achenes or true fruits, commonly called pips or seeds, are more or less embedded but never wholly concealed. A ripe strawberry in fact may be aptly compared to the fruit of a rose turned inside out.
Classification
Harvested strawberriesThere are more than 20 different Fragaria species worldwide. Key to the classification of strawberry species is recognizing that they vary in the number of chromosomes. There are seven basic types of chromosomes that they all have in common. However, they exhibit different polyploidy. Some species are diploid, having two sets of the seven chromosomes (14 chromosomes total). Others are tetraploid (four sets, 28 chromosomes total), hexaploid (six sets, 42 chromosomes total), octoploid (eight sets, 56 chromosomes total), or decaploid (ten sets, 70 chromosomes total).
As a rough rule (with exceptions), strawberry species with more chromosomes tend to be more robust and produce larger plants with larger berries (Darrow).
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