"The function of male penis is not only limited to sperm transfer, but also to remove sperm left in female storage organ from previous matings," Khelifa said.
|
|
In some plants, the hypocotyl becomes enlarged as a storage organ. Examples include cyclamen, gloxinia and celeriac. In cyclamen this storage organ is called a tuber.
|
|
A storage organ is a part of a plant specifically modified for storage of energy (generally in the form of carbohydrates) or water. Storage organs often grow underground, where they are better protected from attack by herbivores. Plants that have an underground storage organ are called geophytes in the Raunkiær plant life-form classification system.The underground storage organ itself is sometimes called a geophyte, but this is not the original usage of the term in the Raunkiær plant life-form classification.
|
|
Bulbs can reproduce vegetatively in a number of ways depending of the type of storage organ the plant has.
|
|
The sperm storage organ removes sperm from males who mate later, which reflects cryptic female choice. Cryptic female choice refers to a female's opportunity to choose with which sperm to fertilize her eggs. It has been suggested that males may have developed this aggressive mate tactic as a result of the female sperm storage organ.
|
|
The Invertebrates: A Synthesis. Oxford: Blackwell Science. Also, all species in Bursovaginoidea have a sperm-storage organ called a bursa. In suborder Scleroperalia, the bursa is cuticular, while in Conophoralia it is not.
|
|
Tuber and roots in genus cyclamen A tuber of Cyclamen purpurascens with three floral trunks The storage organ of the cyclamen is a round tuber that develops from the hypocotyl (the stem of a seedling). It is often mistakenly called a corm, but a corm (found in crocuses, for example) has a papery tunic and a basal plate from which the roots grow. The storage organ of the cyclamen has no papery covering and, depending on the species, roots may grow out of any part. It is therefore properly classified as a tuber (somewhat like a potato).
|
|
S. turbinatum flowers untriggered (left) and after being triggered (right). The floral column will reset to the original position. The majority of the Stylidium species are perennial herbs of which some are geophytes that utilize bulbs as their storage organ. The remaining small group of species consists of ephemeral annuals.
|
|
Agapanthus is a genus of herbaceous perennials that mostly bloom in summer. The leaves are basal, curved, and linear, growing up to long. They are rather leathery and arranged in two opposite rows. The plant has a mostly underground stem called a rhizome (like a ginger 'root') that is used as a storage organ.
|
|
There are approximately 100 described species and certainly many more as yet undescribed. The known species are grouped in two orders. The filospermoids are very long and are characterized by an elongate rostrum. The bursovaginoids have paired sensory organs and are characterized by the presence of a penis and a sperm-storage organ called a bursa.
|
|
In diapause, the measurement of fats and lipids levels a can be as high as 34%. The fat storage organ is substantially larger in migrating and overwintering monarchs compared to the summer generations. Samples of tissue excluding the fat body also show higher levels of free lipids in the hemolymph. Females in diapause show little evidence of mature eggs.
|
|
The rhizome of the genus Diplazium varies from creeping to erect, and is scaly. Its fronds are deciduous or evergreen, are trophopodicThe trophopod is food storage organ described from a number of North American ferns. It consists of the enlarged and modified leaf base filled with starch storage tissue. See W. H. Wagner, Jr. and D. M. Johnson, Taxon, Vol.
|
|
The other members of the genus Drosophila also make very few, giant sperm cells, with D. bifurca being the longest. Such sperm gigantism is thought to have evolved via a Fisherian runaway process, with a genetic link between sperm length and the length of the female seminal receptacle length (sperm-storage organ) combined with an increasing competitive advantage of longer sperm as the seminal receptacle evolves to be longer.
|
|
Polyandrous females mate with many male partners. Females of many species of arthropod, mollusk and other phyla have a specialized sperm-storage organ called the spermatheca in which the sperm of different males sometimes compete for increased reproductive success. Species of crickets, specifically Gryllus bimaculatus, are known to exhibit polyandrous sexual selection. Males will invest more in ejaculation when competitors are in the immediate environment of the female.
|
|
Taro corms for sale in a Réunion market A corm, bulbo-tuber, or bulbotuber is a short, vertical, swollen underground plant stem that serves as a storage organ that some plants use to survive winter or other adverse conditions such as summer drought and heat (perennation). The word cormous usually means plants that grow from corms, parallel to the terms tuberous and bulbous to describe plants growing from tubers and bulbs.
|
|
Many fungi and bacteria cause soft rots on several fruits and vegetables. Species of the fungus, Rhizopus and bacterium Erwinia are two such commonly found pathogens causing soft rots. In a dry rot, the storage organ becomes hard and dry, and in some diseases, there is rapid loss of water and the infected organs become shriveled, wrinkled, and leathery. Dry rots showing such symptoms are referred to as mummifications.
|
|
The word "bulb" has a somewhat different meaning to botanists than it does to gardeners and horticulturalists. In gardening, a "bulb" is a plant's underground or ground-level storage organ that can be dried, stored and sold in this state, and then planted to grow again. Many bulbs in this sense are produced by geophytes – plants whose growing point is below ground level. However, not all bulbs in the gardening sense are produced by geophytes.
|
|
Geckos have a simple diet of live insects and smaller organisms. The diet of a gecko includes, but is not limited to, spiders, isopodas, moths, flies, grasshoppers and caterpillars. As expected, due to an individual's size and preference, the diet has a lot of variation. In other gecko species, the tail acts as a storage organ which can hold reserves of fat which the individual can use in times of food scarcity.
|
|
The Asphodelus ramosus is a geophyte, having an underground storage organ which enables the plant to survive adverse conditions, such as excessive heat and drought. Its leaves, growing to a height of –, contain alkaloids that are harmful to sheep and goats in the wet, winter months, but during the summer when their leaves dry out, they lose their toxicity.Avi Shmida, MAPA's Dictionary of Plants and Flowers in Israel, Tel-Aviv 2005, s.v. Asphodelus aestivus auct.
|
|
Spongy, white roots enable it to absorb water quickly from a wet rock surface whilst at other times, reflect light to avoid overheating during long dry spells. The stems or pseudobulbs may be erect or spreading but are always succulent, serving as a water storage organ during dry periods. The roots emerge from the thicker base end of the pseudobulb, which tapers towards the tip. The pseudobulbs are long and in diameter and have between three and six leaves near the tip.
|
|
The pseudobulb is a storage organ found in many epiphytic and terrestrial sympodial orchids. It is derived from a thickening of the part of a stem between leaf nodes and may be composed of just one internode or several, termed heteroblastic and homoblastic respectively. All leaves and inflorescences usually arise from this structure. Pseudobulbs formed from a single internode produce the leaves and inflorescence from the top, while those that are formed from several internodes can possess leaves along its length.
|
|
A geophyte (earth+plant) is a plant with an underground storage organ including true bulbs, corms, tubers, tuberous roots, enlarged hypocotyls, and rhizomes. Most plants with underground stems are geophytes but not all plants that are geophytes have underground stems. Geophytes are often physiologically active even when they lack leaves. They are able to survive during adverse environmental conditions by going into a state of quiesce and later resume growth from their storage organs, which contain reserves of carbohydrates and water, when the environmental conditions are favourable again.
|
|
The hard clay soils acts as insulation; all other species in subgenus Lasiocephala use dense white hairs for insulation. Dormancy is typically broken with the first rains of the wet season and growth proceeds quickly. New growth, such as a new fibrous root system, new leaves, and the inflorescence, must build up reserves and set seed; a short wet season and sudden drought may cut the growing season considerably. New roots are white and fleshy, mostly serving as a water storage organ, while older roots become thinner and mostly anchor the plant.
|
|
A rhizome is the main stem of the plant. A stolon is similar to a rhizome, but a stolon sprouts from an existing stem, has long internodes, and generates new shoots at the end, such as in the strawberry plant. In general, rhizomes have short internodes, send out roots from the bottom of the nodes, and generate new upward-growing shoots from the top of the nodes. A stem tuber is a thickened part of a rhizome or stolon that has been enlarged for use as a storage organ.
|
|
Commercial tulip field in Hillegom, the Netherlands Bulbs can be evergreen, such as Clivia, Agapanthus and some species and varieties of Iris and Hemerocallis. However, the majority are deciduous, dying down to the storage organ for part of the year. This characteristic has been taken advantage of in the commercialization of these plants. At the beginning of the rest period the bulbs can be dug out of the ground and prepared for sale as if they remain dry they do not need any nutrition for weeks or months.
|
|
In the families Ambystomatidae and Salamandridae, the male's tail, which is larger than that of the female, is used during the amplexus embrace to propel the mating couple to a secluded location. In terrestrial species, the tail moves to counterbalance the animal as it runs, while in the arboreal salamander and other tree-climbing species, it is prehensile. The tail is also used by certain plethodontid salamanders that can jump, to help launch themselves into the air. The tail is used in courtship and as a storage organ for proteins and lipids.
|
|
Larger males tend to engage in more tapping sequences and have higher fertilization success, either due to their size or due to female preference for large males. During copulation, male sperm is deposited into a storage organ called the bursa copulatrix. Sperm from previous matings is mostly stored in doublet storage tubes called spermathecae, while sperm from the most recent mating is typically in a separate singlet spermatheca. During male tapping, sperm is moved into the singlet spermatheca, and typically females use the sperm from the singlet spermatheca during egg-laying.
|
|
Cotyledons may be either epigeal, expanding on the germination of the seed, throwing off the seed shell, rising above the ground, and perhaps becoming photosynthetic; or hypogeal, not expanding, remaining below ground and not becoming photosynthetic. The latter is typically the case where the cotyledons act as a storage organ, as in many nuts and acorns. Hypogeal plants have (on average) significantly larger seeds than epigeal ones. They are also capable of surviving if the seedling is clipped off, as meristem buds remain underground (with epigeal plants, the meristem is clipped off if the seedling is grazed).
|
|
Males have conspicuous white marks around the mouth, whereas similar markings are diminutive in females. Males also have a broad hind tibia, rhomboid or triangular in shape and rounded distally, used as a storage organ for aromatic materials. Male forelegs have five tarsal segments, which have dense tufts of hairs (or ‘brushes’) on the ventral surface, that are useful for picking up oily liquids by capillarity. An elongated pit covered by long hairs (a ‘scar’) can also be seen on the outer rear surface of the tibia, which shows two lobes, each of which has an opening into the tibial organ.
|
|
Developing early, the tuberous roots and bloated trunk form a prominent storage organ, which allows the plant to preserve water and thrive in drier climates. Although drought-deciduous, shedding its leaves towards the end of very prolonged dry seasons, it habitually grows as an evergreen under more moderate conditions. Light frost is tolerated, although persistent cold temperatures at higher growing elevations may eventually cause the tree to wither down to the base of its trunk, as well as inducing dormancy in seeds. M. stenopetala trees live between 60 and 100 years, often with sustained productivity until the end of their lifespan.
|
|
A taproot is a large, central, and dominant root from which other roots sprout laterally. Typically a taproot is somewhat straight and very thick, is tapering in shape, and grows directly downward. In some plants, such as the carrot, the taproot is a storage organ so well developed that it has been cultivated as a vegetable. The taproot system contrasts with the adventitious or fibrous root system of plants with many branched roots, but many plants that grow a taproot during germination go on to develop branching root structures, although some that rely on the main root for storage may retain the dominant taproot for centuries, for example Welwitschia.
|
|
The initial segment of the epididymis, first described in the guinea pig epididymis, is a histologically distinct region of tall pseudostratified columnar epithelium that receives spermatozoa from the ductuli efferentes (Figure 1). The epididymis is the primary sperm storage organ in male reptiles. In all reptiles and mammals the sperm storage region of the epididymis can objectively be identified as that distal extremity of the epididymis that exhibits a widened diameter of duct which contains additional layers of circumferential smooth muscle capable of contraction during ejaculation in direct continuity with the vas deferens (Figure 1). This sperm storage region has been described as the anatomical cauda epididymis or the histologic terminal segment of the epididymis.
|
|
Whether cane-like (with many joints) or spherical (with one or few joints), they are all produced from a long-lived creeping stem called a rhizome which may itself be climbing or pendulous. The pseudobulbs are relatively short lived (1–5 years), but are continually produced from the growing tip of the rhizome and may persist for years after its last leaves senesce. The term pseudobulb is used to distinguish the above-ground storage organ from other storage organs derived from stems that were underground, namely corms or true bulbs, a combination of an underground stem and storage leaves. Strictly speaking, there is no clear distinction between the pseudobulb and corm structures.
|
|
Dense innervation of arteries in seals by sympathetic nerves may be part of a system for maintaining vasoconstriction of the dive response independent of local metabolite induced vasodilation. Venous capacitance is highly developed, especially in phocid seals and whales, and includes a large hepatic sinus and posterior vena cava, and is thought to be related to the large blood volume of the animals. The relatively large spleen also injects extremely high hematocrit blood into the hepatic sinus during dives, and is a significant storage organ for red blood cells. Parallel counter-flowing arteries and veins characteristic of countercurrent exchange units are present in the dorsal fins, flukes, and flippers of cetaceans, and are considered to conserve body heat by transferring it to the returning venous flow before arterial blood is exposed to the high heat-loss areas.
|
|
The yolk of a chicken egg Among animals which produce eggs, the yolk (also known as the vitellus) is the nutrient-bearing portion of the egg whose primary function is to supply food for the development of the embryo. Some types of egg contain no yolk, for example because they are laid in situations where the food supply is sufficient (such as in the body of the host of a parasitoid) or because the embryo develops in the parent's body, which supplies the food, usually through a placenta. Reproductive systems in which the mother's body supplies the embryo directly are said to be matrotrophic; those in which the embryo is supplied by yolk are said to be lecithotrophic. In many species, such as all birds, and most reptiles and insects, the yolk takes the form of a special storage organ constructed in the reproductive tract of the mother.
|
|