Ovary (botany)

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Longitudinal section of female flower of a squash showing pistil (=ovary+style+stigma), ovules, and petals. The petals and sepals are above the ovary; such a flower is said to have an inferior ovary, or the flower is said to be epigynous. Femalesquash3747.JPG
Longitudinal section of female flower of a squash showing pistil (=ovary+style+stigma), ovules, and petals. The petals and sepals are above the ovary; such a flower is said to have an inferior ovary, or the flower is said to be epigynous.
Cross section of a tulip ovary Ovary (botany) (255 30) Tulip; cross-section.jpg
Cross section of a tulip ovary

In the flowering plants, an ovary is a part of the female reproductive organ of the flower or gynoecium. Specifically, it is the part of the pistil which holds the ovule(s) and is located above or below or at the point of connection with the base of the petals and sepals. The pistil may be made up of one carpel or of several fused carpels (e.g. dicarpel or tricarpel), and therefore the ovary can contain part of one carpel or parts of several fused carpels. Above the ovary is the style and the stigma, which is where the pollen lands and germinates to grow down through the style to the ovary, and, for each individual pollen grain, to fertilize one individual ovule. Some wind pollinated flowers have much reduced and modified ovaries.

Contents

Fruits

A fruit is the mature, ripened ovary of a flower following double fertilization in an angiosperm. Because gymnosperms do not have an ovary but reproduce through fertilization of unprotected ovules, they produce naked seeds that do not have a surrounding fruit, this meaning that juniper and yew "berries" are not fruits, but modified cones. Fruits are responsible for the dispersal and protection of seeds in angiosperms and cannot be easily characterized due to the differences in defining culinary and botanical fruits.

Development

Simple fruits are derived from one ovary of a single flower, while aggregate fruits are derived from many ovaries of one flower. Differently, a multiple fruit is derived from multiple ovaries each from their own individual flowers. Fruit Type Diagram.png
Simple fruits are derived from one ovary of a single flower, while aggregate fruits are derived from many ovaries of one flower. Differently, a multiple fruit is derived from multiple ovaries each from their own individual flowers.

After double fertilization and ripening, the ovary becomes the fruit, the ovules inside the ovary become the seeds of that fruit, and the egg within the ovule becomes the zygote. [1] [2] Double fertilization of the central cell in the ovule produces the nutritious endosperm tissue that surrounds the developing zygote within the seed. [2] Angiosperm ovaries do not always produce a fruit after the ovary has been fertilized. Problems that can arise during the developmental process of the fruit include genetic issues, harsh environmental conditions, and insufficient energy which may be caused by competition for resources between ovaries; any of these situations may prevent maturation of the ovary. [3] [4] [5] [6]

Dispersal and evolutionary significance

The orange is a simple fruit called a hesperidium. It is the mature ovary of a single orange blossom. Though it seems to have sections when cut open, all of these sections together come from a single ovary that develops into different layers. OrangeBloss wb.jpg
The orange is a simple fruit called a hesperidium. It is the mature ovary of a single orange blossom. Though it seems to have sections when cut open, all of these sections together come from a single ovary that develops into different layers.

Fruits are important in the dispersal and protection of seeds, and variation in fruit shape or size results from an evolutionary response that aids in the dispersal of seeds in different environments. [8] [9] For example, the seeds of large fleshy fruits are often dispersed through endozoochory; this means that animals consume the fleshy fruit and as a result disperse its seeds with their movement. [10] The seeds of fruits can be dispersed by endozoochory, gravity, wind, or other means.

Complications and types of fruits

There are some complications to the definition of a fruit, as not all botanical fruits can be identified as culinary fruits. A ripened ovary may be a fleshy fruit such as a grapefruit or a dry fruit such as a nut. Further complicating this, culinary nuts are not always botanical nuts; some culinary nuts such as the coconut and almond are another type of fruit called a drupe. [11] [12]

In this same way, not all "fruits" are true fruits. A true fruit only consists of the ripened ovary and its contents. Fruits can be separated into three major categories: simple fruits, aggregate fruits, and multiple fruits. Simple fruits like oranges are formed from a single ovary which may or may not consist of multiple parts, while aggregate and multiple fruits are formed from several ovaries together. [13] Aggregate fruits like raspberries are the ripened ovaries of one flower that form a single fruit, and multiple fruits like pineapples are formed from the ovaries of separate flowers that are close together. [13] [14] [15]

Because aggregate and multiple fruits are formed from many ripened ovaries together, they are actually infructescences or groups of fruits that are arranged together in a structure. [13] Some fruits, like the apple, are accessory fruits which can include other parts of the flower such as the receptacle, hypanthium, perianth, or calyx in addition to the mature and ripened ovary. [16]

Parts of the ovary

Locules are chambers within the ovary of the flower and fruits. The locules contain the ovules (seeds), and may or may not be filled with fruit flesh. Depending on the number of locules in the ovary, fruits can be classified as uni-locular (unilocular), bi-locular, tri-locular or multi-locular. Some plants have septa between the carpels; the number of locules present in a gynoecium may be equal to or less than the number of carpels, depending on whether septa are present.

The ovules are attached to parts of the interior ovary walls called the placentae. Placental areas occur in various positions, corresponding to various parts of the carpels that make up the ovary. See Ovule#Location within the plant. An obturator is present in the ovary of some plants, near the micropyle of each ovule. It is an outgrowth of the placenta, important in nourishing and guiding pollen tubes to the micropyle. [17]

The ovary of some types of fruit is dehiscent; the ovary wall splits into sections called valves. There is no standard correspondence between the valves and the position of the septa; the valves may separate by splitting the septa (septicidal dehiscence), or by spitting between them (loculicidal dehiscence), or the ovary may open in other ways, as through pores or because a cap falls off.

Classification based on position

Ovary insertion: I) superior; II) half-inferior; III) inferior. a androecium g gynoecium p petals s sepals r receptacle. The insertion point is where a, p, and s converge. Ovary position.svg
Ovary insertion: I) superior; II) half-inferior; III) inferior. a androecium g gynoecium p petals s sepals r receptacle. The insertion point is where a, p, and s converge.

The terminology of the positions of ovaries is determined by the insertion point, where the other floral parts (perianth and androecium) come together and attach to the surface of the ovary. [18] If the ovary is situated above the insertion point, it is superior; if below, inferior.

Superior ovary

A superior ovary is an ovary attached to the receptacle above the attachment of other floral parts. A superior ovary is found in types of fleshy fruits such as true berries, drupes, etc. A flower with this arrangement is described as hypogynous. Examples of this ovary type include the legumes (beans and peas and their relatives).

Half-inferior ovary

A half-inferior ovary (also known as “half-superior”, “subinferior,” or “partially inferior,”) is embedded or surrounded by the receptacle. [19] This occurs in flowers of the family Lythraceae, which includes the crape myrtles. Such flowers are termed perigynous or half-epigynous. In some classifications, half-inferior ovaries are not recognized and are instead grouped with either the superior or inferior ovaries.

More specifically, a half-inferior ovary has nearly equal portions of ovary above and below the insertion point. Other varying degrees of inferiority can be described by other fractions. For instance, a "one-fifth inferior ovary" has approximately one fifth of its length under the insertion point. Likewise, only one quarter portion of a "three-quarters inferior ovary" is above the insertion.

Inferior ovary

An inferior ovary lies below the attachment of other floral parts. A pome is a type of fleshy fruit that is often cited as an example, but close inspection of some pomes (such as Pyracantha ) will show that it is really a half-inferior ovary. Flowers with inferior ovaries are termed epigynous. Some examples of flowers with an inferior ovary are orchids (inferior capsule), Fuchsia (inferior berry), banana (inferior berry), Asteraceae (inferior achene-like fruit, called a cypsela) and the pepo of the squash, melon and gourd family, Cucurbitaceae.

See also

Related Research Articles

<span class="mw-page-title-main">Fruit</span> Seed-bearing part of a flowering plant

In botany, a fruit is the seed-bearing structure in flowering plants that is formed from the ovary after flowering.

<span class="mw-page-title-main">Drupe</span> Fleshy fruit with hard inner layer (endocarp or stone) surrounding the seed

In botany, a drupe is an indehiscent type of fruit in which an outer fleshy part surrounds a single shell of hardened endocarp with a seed (kernel) inside. These fruits usually develop from a single carpel, and mostly from flowers with superior ovaries.

<span class="mw-page-title-main">Accessory fruit</span> Botanical category of fruit

An accessory fruit is a fruit that contains tissue derived from plant parts other than the ovary. In other words, the flesh of the fruit develops not from the floral ovary, but from some adjacent tissue exterior to the carpel. As a general rule, the accessory fruit is a combination of several floral organs, including the ovary. In contrast, true fruit forms exclusively from the ovary of the flower.

<span class="mw-page-title-main">Capsule (fruit)</span> Type of simple, dry rarely fleshy, dehiscent fruit

In botany a capsule is a type of simple, dry, though rarely fleshy dehiscent fruit produced by many species of angiosperms.

<span class="mw-page-title-main">Pome</span> Fruit with apple-like features

In botany, a pome is a type of fruit produced by flowering plants in the subtribe Malinae of the family Rosaceae. Pome fruits consist of a central "core" containing multiple small seeds, which is enveloped by a tough membrane and surrounded by an edible layer of flesh. Pome fruit trees are deciduous, and undergo a dormant winter period that requires cold temperatures to break dormancy in spring. Well-known pomes include the apple, pear, and quince.

<span class="mw-page-title-main">Ovule</span> Female plant reproductive structure

In seed plants, the ovule is the structure that gives rise to and contains the female reproductive cells. It consists of three parts: the integument, forming its outer layer, the nucellus, and the female gametophyte in its center. The female gametophyte — specifically termed a megagametophyte— is also called the embryo sac in angiosperms. The megagametophyte produces an egg cell for the purpose of fertilization. The ovule is a small structure present in the ovary. It is attached to the placenta by a stalk called a funicle. The funicle provides nourishment to the ovule.On the basis of the relative position of micropyle, body of the ovule, chalaza and funicle, there are six types of ovules . (a) Orthotropous ovule - the micropyle, chalaza and funicle all lie in the same straight line, this is the most primitive type of ovule . Eg: Piper, polygonum and cycas.

<span class="mw-page-title-main">Plant reproductive morphology</span> Parts of plant enabling sexual reproduction

Plant reproductive morphology is the study of the physical form and structure of those parts of plants directly or indirectly concerned with sexual reproduction.

<span class="mw-page-title-main">Dehiscence (botany)</span> Splitting of a mature plant structure along built-in line of weakness to release contents

Dehiscence is the splitting of a mature plant structure along a built-in line of weakness to release its contents. This is common among fruits, anthers and sporangia. Sometimes this involves the complete detachment of a part. Structures that open in this way are said to be dehiscent. Structures that do not open in this way are called indehiscent, and rely on other mechanisms such as decay or predation to release the contents.

<span class="mw-page-title-main">Gynoecium</span> Female organs of a flower

Gynoecium is most commonly used as a collective term for the parts of a flower that produce ovules and ultimately develop into the fruit and seeds. The gynoecium is the innermost whorl of a flower; it consists of pistils and is typically surrounded by the pollen-producing reproductive organs, the stamens, collectively called the androecium. The gynoecium is often referred to as the "female" portion of the flower, although rather than directly producing female gametes, the gynoecium produces megaspores, each of which develops into a female gametophyte which then produces egg cells.

<span class="mw-page-title-main">Aggregate fruit</span> Category of fruit

An aggregate fruit or etaerio is a fruit that develops from the merger of several ovaries that were separated in a single flower. In contrast, a simple fruit develops from one ovary, and a multiple fruit develops from multiple flowers. In languages other than English, the meanings of "aggregate" and "multiple" fruit are reversed, so that "aggregate" fruits merge several flowers. The differences in meaning are due to a reversal in the terminology by John Lindley, which has been followed by most English-language authors.

<span class="mw-page-title-main">Multiple fruit</span> Fruiting bodies formed from a cluster of fruiting flowers (inflorescence)

Multi-fruits, also called collective fruits, are fruiting bodies formed from a cluster of flowers, the inflorescence. Each flower in the inflorescence produces a fruit, but these mature into a single mass. After flowering, the mass is called an infructescence. Examples are the fig, pineapple, mulberry, osage orange, and jackfruit.

<span class="mw-page-title-main">Berry (botany)</span> Botanical fruit with fleshy pericarp, containing one or many seeds

In botany, a berry is a fleshy fruit without a stone (pit) produced from a single flower containing one ovary. Berries so defined include grapes, currants, and tomatoes, as well as cucumbers, eggplants (aubergines), persimmons and bananas, but exclude certain fruits that meet the culinary definition of berries, such as strawberries and raspberries. The berry is the most common type of fleshy fruit in which the entire outer layer of the ovary wall ripens into a potentially edible "pericarp". Berries may be formed from one or more carpels from the same flower. The seeds are usually embedded in the fleshy interior of the ovary, but there are some non-fleshy exceptions, such as Capsicum species, with air rather than pulp around their seeds.

<span class="mw-page-title-main">Cleomaceae</span> Family of flowering plants

The Cleomaceae are a small family of flowering plants in the order Brassicales, comprising about 220 species in two genera, Cleome and Cleomella. These genera were previously included in the family Capparaceae, but were raised to a distinct family when DNA evidence suggested the genera included in it are more closely related to the Brassicaceae than they are to the Capparaceae. The APG II system allows for Cleomaceae to be included in Brassicaceae. Cleomaceae includes C3, C3–C4, and C4 photosynthesis species.

This page provides a glossary of plant morphology. Botanists and other biologists who study plant morphology use a number of different terms to classify and identify plant organs and parts that can be observed using no more than a handheld magnifying lens. This page provides help in understanding the numerous other pages describing plants by their various taxa. The accompanying page—Plant morphology—provides an overview of the science of the external form of plants. There is also an alphabetical list: Glossary of botanical terms. In contrast, this page deals with botanical terms in a systematic manner, with some illustrations, and organized by plant anatomy and function in plant physiology.

<span class="mw-page-title-main">Locule</span> Small cavity or compartment within an organ or part of an organism

A locule or loculus is a small cavity or compartment within an organ or part of an organism.

<span class="mw-page-title-main">Fruit (plant structure)</span> Internal makeup of fruits

Fruits are the mature ovary or ovaries of one or more flowers. They are found in three main anatomical categories: aggregate fruits, multiple fruits, and simple fruits.

This glossary of botanical terms is a list of definitions of terms and concepts relevant to botany and plants in general. Terms of plant morphology are included here as well as at the more specific Glossary of plant morphology and Glossary of leaf morphology. For other related terms, see Glossary of phytopathology, Glossary of lichen terms, and List of Latin and Greek words commonly used in systematic names.

<span class="mw-page-title-main">Simple fruit</span>

Simple fruits are the result of the ripening-to-fruit of a simple or compound ovary in a single flower with a single pistil. In contrast, a single flower with numerous pistils typically produces an aggregate fruit; and the merging of several flowers, or a 'multiple' of flowers, results in a 'multiple' fruit. A simple fruit is further classified as either dry or fleshy.

<span class="mw-page-title-main">Floral morphology</span>

In botany, floral morphology is the study of the diversity of forms and structures presented by the flower, which, by definition, is a branch of limited growth that bears the modified leaves responsible for reproduction and protection of the gametes, called floral pieces.

References

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  3. ↑ Stephenson, Andrew G. (1980). "Fruit Set, Herbivory, Fruit Reduction, and the Fruiting Strategy of Catalpa Speciosa (Bignoniaceae)". Ecology. 61 (1): 57–64. doi:10.2307/1937155. ISSN   0012-9658. JSTOR   1937155.
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  5. ↑ Pawsey, C. K. (1960-01-01). "Cone Production Reduced, Apparently by Drought, in the South-East of South Australia". Australian Forestry. 24 (1): 74–75. doi:10.1080/00049158.1960.10675890. ISSN   0004-9158.
  6. ↑ Wyatt, Robert (1982). "Inflorescence Architecture: How Flower Number, Arrangement, and Phenology Affect Pollination and Fruit-Set". American Journal of Botany. 69 (4): 585–594. doi:10.2307/2443068. ISSN   0002-9122. JSTOR   2443068.
  7. ↑ Kim, In-Sun (2003). "Sequential Changes of Pericarp Ultrastructure in Citrus reticulata Hesperidium". Applied Microscopy. 33 (1): 79–92. ISSN   2287-5123.
  8. ↑ Gardocki, Mary; Zablocki, Heather; El-Keblawy, Ali; Freeman, D. (2000). "Heterocarpy in Calendula micrantha (Asteraceae): The effects of competition and availability of water on the performance of offspring from different fruit morphs". Evolutionary Ecology Research. 2: 701–718.
  9. ↑ Jordano, Pedro (1995). "Angiosperm Fleshy Fruits and Seed Dispersers: A Comparative Analysis of Adaptation and Constraints in Plant-Animal Interactions". The American Naturalist. 145 (2): 163–191. doi:10.1086/285735. hdl: 10261/42645 . ISSN   0003-0147. JSTOR   2463122. S2CID   86615972.
  10. ↑ Willson, Mary (2000). Fenner, M. (ed.). "The Ecology of Seed Dispersal". Seeds: The Ecology of Regeneration in Plant Communities (2nd ed.): 85–110. doi:10.1079/9780851994321.0085. ISBN   9780851994321.
  11. ↑ Geiselhart, Sabine; Hoffmann-Sommergruber, Karin; Bublin, Merima (2018-08-01). "Tree nut allergens". Molecular Immunology. 100: 71–81. doi: 10.1016/j.molimm.2018.03.011 . ISSN   0161-5890. PMID   29680588. S2CID   5069722.
  12. ↑ Kusari, Ayan; Han, Allison; Eichenfield, Lawrence (2018-10-30). "Recent advances in understanding and preventing peanut and tree nut hypersensitivity". F1000Research. 7: 1716. doi: 10.12688/f1000research.14450.1 . ISSN   2046-1402. PMC   6208566 . PMID   30467518.
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  14. ↑ Graham, Julie; Jennings, Nikki (2009). Jain, S. Mohan; Priyadarshan, P.M. (eds.). Breeding Plantation Tree Crops: Temperate Species. New York, NY: Springer Science & Business Media. pp. 233–248. ISBN   978-0-387-71203-1.
  15. ↑ Moyle, Richard; Fairbairn, David J.; Ripi, Jonni; Crowe, Mark; Botella, Jose R. (2005). "Developing pineapple fruit has a small transcriptome dominated by metallothionein". Journal of Experimental Botany. 56 (409): 101–112. doi: 10.1093/jxb/eri015 . PMID   15520025.
  16. ↑ Watkins, Chris B.; Liu, Rui Hai (2011). "Pome Fruit". In Terry, Leon (ed.). Health-promoting Properties of Fruits and Vegetables. Wallingford: CABI. pp. 196–217. ISBN   978-1-84593-529-0. OCLC   758335853.
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  18. ↑ Soltis, Douglas E.; Fishbein, Mark; Kuzoff, Robert K. (2003). "Evolution of Epigyny". International Journal of Plant Sciences. 164 (S5): S251–S264. doi:10.1086/376876. S2CID   83871403.
  19. ↑ Soltis, Douglas E.; Hufford, Larry (2002). "Ovary Position Diversity in Saxifragaceae". International Journal of Plant Sciences. 163 (2): 277–293. doi:10.1086/324528. S2CID   85947971.
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