Sometimes the many separate apocarpous ovaries were in a single flower, like a raspberry and the resulting fruit is an aggregate. Sometimes the compound fruit comes from many flowers in an inflorescence like a pineapple and it is a multiple.
The ovary wall is the predecessor of the fruit wall, and is divided into three layers, the endocarp, closest to the seed, the mesocarp in the middle and the exocarp to the outside, and often we differentiate fruit types by what happens to these layers.
When the endocarp becomes hard or bony enclosing a single seed we have a drupe. These are the so-called stone fruits, all in the rose family, that make up an important economic grouping. Cherries, peaches, plums, apricots and almonds belong here, and these are truly the idea of sweet fruit that makes our mouth water. Beware of the easily opened pit, and resist the temptation to suck on the seed, because these seeds are equipped with a bit of cyanide to discourage predation.
They are all from hypogynous flowers with superior ovaries and you can check this and show it in your drawings when you can see the remains of the calyx attached to the stem. The minimal scar at the opposite side of the fruit is the place where the style was attached.
Another fruit type formed from a superior ovary, but one where the pericarp is succulent, and not differentiated into separate layers is the berry. A grape is an example, as are the fruits of the nightshades, tomatoes, peppers, and eggplants. Now we are dealing with succulent entities that are no longer sweet, that we would classify unbotanically as vegetables. Blueberries and gooseberries for example, are classed as false berries because, although they are from fleshy and undifferentiated pericarps, they are from inferior ovaries.
Mesocarp, endocarp and swollen placenta are eaten. Dry Fruits Dry fruits are the fruits in which pericarp or fruit wall becomes dry at maturity. The pericarp is brittle or hard. On the basis of dehiscence dry fruits are classified into three categories :- A.
Dry Dehiscent Fruits Dry dehiscent fruits burst automatically on ripening and discharge their seeds. The dry fruit wall shrinks and splits up exposing the seeds. They are :- Legume , Follicle , Siliqua and Capsule a. Legume Legume is a dry dehiscent fruit developed from monocarpellary, unilocular and superior ovary. The fruit splits along the dorsal and ventral sutures into two valves. The seeds attached to the valves are discharged at this stage. Legume is found in many members of leguminosae b.
Follicle Follicle is a dry dehiscent fruit developed from superior ovary. Normally follicles are present as fruitlets in aggregate fruits. Rarely follicles occur singly Banksia and Hakea.
Siliqua Siliqua is a dry dehiscent fruit developed from bicarpellary, syncarpous and superior ovary. The dehiscence of the fruit begins at the base and proceeds upwards. Capsule Capsule is a dry dehiscent fruit developed from multicarpellary syncarpous and superior ovary. Based on the type of dehiscence, capsules are classified into five types Septicidal capsule. Dry Indehiscent Fruits The dry indehiscent fruits do not split at maturity.
A dry indehiscent fruit usually consists of only one seed. The fruit containing the seed falls off from the plant at maturity. The fruit wall disintegrates slowly and release the seed. Dry indehiscent fruits are classified into five types :- a. Caryopsis Caryposis is a one-seeded, dry indehiscent fruit developed from a monocarpellary, unilocular and superior ovary. In this fruit pericarp fuses with the seed coat. This fruit is seen in the members of family poaceae gramineae , for example Oryza rice and Triticum wheat.
Achene It is a one-seeded, dry, indehiscent fruit developed from a monocarpellary, unilocular and superior ovary. In this fruit pericarp, and seed coat are not fused. Pericarp is leathery or thin. Achenes are found as fruitlets in aggregate fruits. Aggregates of achenes are seen in Clematis. Nut It is a one-seeded and one chambered dry, indehiscent fruit developed from a multicarpellary, syncarpous and superior ovary. The fruit wall is hard and woody.
Since abortion of all ovules occur except one, only one-seeded and one- chambered fruit is formed from multicarpellary and syncarpous ovary. Example Terminalia chebula, Anacardiun occidentale cashewnut and Quercus oak. Cypsela Cypsela is a one seeded and one chambered dry indehiscent fruit developed from bicarpellary, syncarpous, unilocular and inferior ovary.
Pericarp is thin and free from the seed coat. Cypsela is the characteristic fruit of family compositae. The fruit consists of persistent pappus which is the modified calyx. In Helianthus pappus is hairy. Samara It is a one-seeded dry indehiscent fruit developed from monocarpellary or multicarpellary and superior ovary.
The pericarp is extended into wing like structures which help in the dispersal of fruit. Examples of samara are Gyrocarpus and Pterocarpus. Schizocarpic Fruits The schizocarpic fruits break up into one seeded bits at maturity. The one-seeded bits are called mericarps. Each mericarp consists of one seed. The seed is liberated only after the decay of pericarp.
Schizocarpic fruits are considered intermediate between dehiscent and indehiscent fruits. Schizocarpic fruits are classified into four types :- a. Lomentum It is a schizocarpic fruit developed from a monocarpellary, unilocular and superior ovary. The fruit is constricted between the seeds. At maturity the fruit breaks up at the constrictions into one-seeded bits and releases indehiscent one-seeded mericarps. Lomentum is variation of legume and is characteristic of subfamily mimosaceae of fabaceae leguminosae , for example, Acacia and Hedysarum.
Carcerulus It is a schizocarpic fruit developed from multicarpellary syncarpous and superior ovary. The fruit separates into 2 to 3 - seeded indehiscent mericarps. The number of mericarps is equal to the number of locules, for example, Althea, Abutilon and Malva. In Ocimum the carcerulus is developed from a bicarpellary, syncarpous, superior and tetralocular ovary. The fruit separates into four indehiscent nutlets. Cremocarp It is a schizocarpic fruit developed from bicarpellary, syncarpous and inferior ovary.
Do the same with a grain that has been thoroughly soaked in water. When this skin like structure has been removed, what structures are left? Examine a demonstration microscope showing the longitudinal section of a corn grain, and note the fused testa or seed coat and pericarp. How many seeds can you see in this structure?
Identify and label the drawings of the caryopsis. Berry: Tomato or Grape. Examine fresh or preserved tomato fruits, noting the stalk or pedicel and the green sepals at the basal end.
Where do you find the remains the style? Does the berry develop from a superior or an inferior ovary? Where were the petals attached? The stamens? Is any other floral part united with the ovary in the formation of this fruit? Is the tomato a true fruit or an accessory fruit? Examine a cross-section of a tomato. How many locules are visible?
Of how many carpels is the fruit composed? How does the berry differ from the legume? Identify and label the drawings of the berry. D The Drupe: Peach Cherries, plums, or even soaked prunes. Examine a fresh or preserved peach. Does this fruit come from a superior or an inferior ovary? What evidence do you have to support your answer? Examine a peach that has been cut lengthwise and one that has been cut crosswise. How many carpels are involved in the formation of the peach? What part of the ovary wall is the rough, fuzzy skin?
What part of the fruit forms the edible portion of the fruit? What part forms the stone or pit? How many seeds does this a drupe contain? Identify and label the drawing of a drupe. The Pome: Apple Crab apple, pear, or quince. Examine the fruit of the apple. Find the fruit stalk or pedicel, and see whether you find near its upper end any scars that might mark the former location of the other flower parts.
Examine the other end of the fruit. What are the small, pointed structures which you find there? How many of these structures are there? Do you find any evidence of stamens? Does the pome develop from an epigynous or hypgynous flower? Examine the cross-section of an apple, noting the star-shaped core. What are the.
How many of them are there? Is the pome a true fruit or an accessory fruit? Identify and label the drawings of the pome. Identification of Miscellaneous Fruits. There is a key for the identification of fruits at the end of this exercise. Study the various fruits available in the laboratory, having your instructor name them for you if necessary, and record your information on each one on the Table provided. Label the drawings of all of the fruits you have identified. Characteristics of Some Common Fruits.
Name of. Dry or. Type of. Types of Fruits: Label the fruit type of each of the drawings below and on the next two pages. Key to the Classification of Fruits. Simple fruits, formed from a single ovary or carpel Compound fruits, formed from several carpels or ovaries Dry fruits Fleshy fruits Fruit dehiscent Fruit indehiscent Fruit derived from one carpel only Fruit derived from one to several carpels Fruit splitting at maturity along one suture Fruit splitting at maturity along two sutures Fruit formed of 2 carpels, separating at maturity, leaving a persistent partition.
Fruit formed of several carpels Fruit several to many-seeded, breaking at maturity into several one-seeded. Fruit not as above, generally one-seeded Seed coat firmly united with pericarp at all points Seed coat not attached to pericarp at all points Pericarp thin, with one or two wings Pericarp lacking wings Fruit coat very hard Fruit coat not particularly hard Fruit composed of 2 carpels, separating at maturity into two 1-seeded halves or.
Fruit coat thin, not separating; fruit small, 1-seeded Fleshy part of fruit derived from ovary only Fleshy part of fruit derived, at least in part, from the receptacle Entire ovary becoming fleshy at maturity Outer part of ovary fleshy,.
Fruit fleshy or juicy, composed of several usually 10 carpels, each with 2 seeds; rind leathery Fruit fleshy, of several carpels, each with one to several seeds; leathery rind. Pistils several, separate, non-fleshy, enclosed by the fleshy or semi-fleshy receptacle. Ovary compound, carpels united Ovary wall fleshy, berry-like, with hard rind Inner part of ovary wall papery or cartilaginous, outer part fleshy, surrounded.
Many simple fruits, usually achenes or drupes, derived from separate carpels of one. Aggregate Fruit. Many simple fruits derived from the carpels of separate flowers Flowers borne within an enlarged hollow, fleshy receptacle Flowers borne upon the surface of a more or less fleshy receptacle Multiple Fruit.
Modified Structures in Plants. Many shoot systems, both stems and leaves, have modifications for special purposes. The leaves of carnivorous plants are famous examples of modified structures which are used for trapping and digesting insects and other small organisms. Just for curiosity observe the many stem, leaf, and shoot modifications on display.
Common Underground Stems and Shoots. Other Modified Stems.
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