In botany, a capsule is a type of simple, dry, though rarely fleshy dehiscent fruit produced by many species of angiosperms (flowering plants). [1] [2]
In botany, a capsule is a type of simple, dry, though rarely fleshy dehiscent fruit produced by many species of angiosperms (flowering plants). [1] [2]
The capsule (Latin: capsula, small box) is derived from a compound (multicarpellary) ovary. [2] A capsule is a structure composed of two or more carpels. In (flowering plants), the term locule (or cell) is used to refer to a chamber within the fruit. Depending on the number of locules in the ovary, fruit can be classified as uni-locular (unilocular), bi-locular, tri-locular or multi-locular. The number of locules present in a gynoecium may be equal to or less than the number of carpels. The locules contain the ovules or seeds and are separated by septa.
In most cases the capsule is dehiscent, i.e. at maturity, it splits apart (dehisces) to release the seeds within. A few capsules are indehiscent, for example those of Adansonia digitata , Alphitonia , and Merciera . Capsules are often classified into four types, depending on the type and location of dehiscence (see Simpson Fig 9.41 [2] and Hickey & King [3] ).
Loculicidal capsules possess longitudinal lines of dehiscence radially aligned with the locules, i.e. not at the septa, along the midrib or dorsal suture (seam) of the locules. If septa are absent, the dehiscence lines lie between the placentae. This type is common among many members of the Liliaceae such as Lilium (see illustration).
Septicidal capsules have dehiscence lines aligned with the sutures of the ovary septa or placentae, that is between the carpels.
Both loculicidal and septicidal capsules split into distinguishable segments called valves. The valves are a part of the pericarp (fruit wall) that has split away, without enclosing the seed or seeds. The borders of the valves may or may not coincide with the borders of carpels. These valves may remain attached to the fruit or fall off. In septicidal capsules the valves remain in place. In some capsules, the split occurs between carpels, and in others each carpel splits open.
Circumscissile capsules (pyxide, pyxis, pyxidium or lid capsule) have a transverse, rather than longitudinal, dehiscence line, so that the upper part of the capsule dehisces, usually forming a terminal lid (operculum) that opens (see illustration). An example is Plantago . A variant is the Septifragal capsule (valvular capsule) in which the outer walls break away from the septa and (usually axile) placentae as valves.
Poricidal capsules dehisce through pores (openings) in the capsule, as in Papaver , the seeds escaping through these pores.
Examples of other plants that produce capsules include nigella, orchid, willow, cotton, and jimson weed. [2] [4]
Some dry dehiscent fruits form specialised capsule-like structures. A follicle is derived from a single carpel that splits along a suture, as in Magnolia , while a legume splits along two sutures, and are a defining feature of the Fabaceae. Some variants of legumes that have retained vestigial sutures include loments that split transversely into segments, each with a single seed, and indehiscent legumes, such as Arachis hypogaea (peanuts). Capsules derived from two carpels include silicles and siliques that dehisce along two suture lines but retain a partition called the replum, which is a septum with attached seeds. While both are characteristic of Brassicaceae, silicles have a ratio of length to width of no more than 3:1. [5] A schizocarp is derived from a compound ovary with two or more locules which then separate radially as one of the above types, such as a schizocarp of follicles, as in Asclepias (Asclepiadoideae) (see illustration).
A mericarp is a portion of the fruit that separates from the ovary to form a distinct locule unit which encloses the seed, usually-nut-like, as in Apiaceae in which the mericarps are joined by a stalk (carpophore). Thus a schizocarp of mericarps is a structure in which the carpels of a single ovary split to form mericarps. A schizocarp of nutlets is derived from a carpel that becomes lobed, and the lobes become nutlets that split apart. Examples include Boraginaceae and most Lamiaceae, where the styles are attached between the ovary lobes. [2] [4]
Capsules are sometimes mislabeled as nuts, as in the example of the Brazil nut or the Horse-chestnut. A capsule is not a nut because it releases its seeds and it splits apart. Nuts, on the other hand, do not release seeds as they are a compound ovary containing both a single seed and the fruit. Nuts also do not split. In the Brazil nut, a lid on the capsule opens, but is too small to release the dozen or so seeds (the actual "Brazil nut" of commerce) within. These germinate inside the capsule after it falls to the ground.
In botany, a fruit is the seed-bearing structure in flowering plants that is formed from the ovary after flowering.
The stamen is the pollen-producing reproductive organ of a flower. Collectively, the stamens form the androecium.
A nut is a fruit consisting of a hard or tough nutshell protecting a kernel which is usually edible. In general usage and in a culinary sense, a wide variety of dry seeds are called nuts, but in a botanical context "nut" implies that the shell does not open to release the seed (indehiscent).
An achene, also sometimes called akene and occasionally achenium or achenocarp, is a type of simple dry fruit produced by many species of flowering plants. Achenes are monocarpellate and indehiscent. Achenes contain a single seed that nearly fills the pericarp, but does not adhere to it. In many species, what is called the "seed" is an achene, a fruit containing the seed. The seed-like appearance is owed to the hardening of the fruit wall (pericarp), which encloses the solitary seed so closely as to seem like a seed coat.
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.
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.
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.
A silique or siliqua is a type of fruit having two fused carpels with the length being more than three times the width. When the length is less than three times the width of the dried fruit it is referred to as a silicle. The outer walls of the ovary usually separate when ripe, then being named dehiscent, and leaving a persistent partition. Siliques are present in many members of the mustard family, Brassicaceae, but some species have silicles instead. Some species closely related to plants with true siliques have fruits with a similar structure that do not open when ripe; these are usually called indehiscent siliques.
A schizocarp is a dry fruit that, when mature, splits up into mericarps.
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, 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.
Trochodendraceae is the only family of flowering plants in the order Trochodendrales. It comprises two extant genera, each with a single species along with up to five additional extinct genera and a number of extinct species. The living species are native to south east Asia. The two living species both have secondary xylem without vessel elements, which is quite rare in angiosperms. As the vessel-free wood suggests primitiveness, these two species have attracted much taxonomic attention.
Spirostachys africana is a medium-sized deciduous tree with a straight, clear trunk, occurring in the warmer parts of Southern Africa. Its wood is known as tamboti, tambotie, tambootie or tambuti.
In botany, a follicle is a dry unilocular fruit formed from one carpel, containing two or more seeds. It is usually defined as dehiscing by a suture in order to release seeds, for example in Consolida, peony and milkweed (Asclepias).
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.
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.
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.
Macarthuria is a genus of dicotyledonous plants belonging to the family Macarthuriaceae, and consists of about 9 species which are endemic to Australia.
Mollia is a genus of flowering plants belonging to the family Malvaceae. It is within the Grewioideae subfamily, and the Grewieae tribe.
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.
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