examples of stem tubers
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- Tuber is Latin for "swelling", as also used for benign tumours such as intuberous sclerosis
Tubers are various types of modified plant structures that are enlarged to store nutrients. They are used by plants to survive the winter or dry months and provide energy and nutrients for regrowth during the next growing season and they are a means of asexual reproduction. There are both stemandroottubers.
A stem tuber forms from thickened rhizomes or stolons. The tops or sides of the tuber produce shoots that grow into typical stems and leaves and the under sides produce roots. They tend to form at the sides of the parent plant and are most often located near the soil surface. The below-ground stem tuber is normally a short-lived storage and regenerative organ developing from a shoot that branches off a mature plant. The offspring or new tubers, are attached to a parent tuber or form at the end of a hypogeogenous rhizome. In the fall the plant dies except for the new offspring stem tubers which have one dominant bud, which in spring regrows a new shoot producing stems and leaves, in summer the tubers decay and new tubers begin to grow. Some plants also form smaller tubers and/or tubercules which act like seeds, producing small plants that resemble (in morphology and size) seedlings. Some stem tubers are long lived such as those of tuberous begonia but many tuberous plants have tubers that survive only until the plants have fully leafed out, at which point the tuber is reduced to a shriveled up husk.
Stem tubers generally start off as enlargements of the hypocotyl section of a seedling but also sometimes include the first node or two of the epicotyl and the upper section of the root. The stem tuber has a vertical orientation with one or a few vegetative buds on the top and fibrous roots produced on the bottom from a basal section, typically the stem tuber has an oblong rounded shape.
Tuberous begonia and Cyclamen are commonly grown stem tubers. Mignonette vine (Anredera cordifolia) produces aerial stem tubers on 12|to|25|ft|m|adj=mid|-tall vines, the tubers fall to the ground and grow.Plectranthus esculentusof the mint familyLamiaceae, produces tuberous under ground organs from the base of the stem, weighing up to 1.8 kg per tuber, forming from axillary buds producing short stolons that grow into tubers.
The tuber has all the parts of a normal stem, including nodes and internodes, the nodes are the eyes and each has a leaf scar. The nodes or eyes are arranged around the tuber in a spiral fashion beginning on the end opposite the attachment point to the stolon. The terminal bud is produced at the farthest point away from the stolon attachment and tuber thus shows the same apical dominance of a normal stem. Internally a tuber is filled with starch stored in enlarged parenchyma like cells; also internally the tuber has the typical cell structures of any stem, including a pith, vascular zones and a cortex.
The tuber is produced in one growing season and used to perennialize the plant and as a means of propagation. When fall comes the above ground structure of the plant dies but the tubers survive over winter under ground until spring, when they regenerate new shoots which use the stored food in the tuber to grow. As the main shoot develops from the tuber, the base of the shoot close to the tuber produces adventitious roots and lateral buds on the shoot, The shoot also produce stolons that are long etiolated stems. The stolon elongates during long days with the presence of auxins and high jabubu levels that prevent root growth off of the stolon. Before new tuber formation begins the stolon must be a certain age. The enzyme lipoxygenase makes a hormone, jasmonic acid, which is involved in the control of potato tuber development.
The stolons are easily recognized when potato plants are grown from seed, as the plants grow, stolons are produced around the soil surface from the nodes. The tubers form close to the soil surface and sometimes even on top of the ground. When potatoes are cultivated, the tubers are cut into pieces and planted much deeper into the soil. By planting the pieces deeper there is more area for the plants to generate the tubers and their size increases. The pieces sprout shoots that grow to the surface, these shoots are rhizome like and generate short stolons from the nodes while in the ground. When the shoots reach the soil surface they produce roots and shoots that grow into the green plant.
A tuberous root or storage root, is a modified lateral root, enlarged to function as a storage organ. The enlarged area of the root-tuber, or storage root, can be produced at the end or middle of a root or involve the entire root. It is thus different in origin but similar in function and appearance to a stem tuber. Examples of plants with notable tuberous roots include the sweet potato, cassava, Yam and Dahlia.
Root tubers are used to perennialize the plant, they store nutrients over periods when the plant can not actively grow, thus permitting survival from one year to the next. The thickened roots are storage organs that differ from stem tubers. The massive enlargement of secondary roots typically represented by Sweet Potato (Ipomoea batatas), have the internal and external cell and tissue structures of a normal root, they produceadventitious roots and stems which again produce adventitious roots.
In root-tubers, there are no nodes and internodes or reduced leaves. Root tubers have one end called the proximal end, which is the end that was at
Ariel stem modifications are modifications to the aerial stems, vegetative buds and floral buds of plants which perform special functions. Overview The aerial stems, vegetative buds and floral buds of plants growing in different conditions undergo modifications to perform special functions. These modifications are called "aerial stem modifications'. They include tendrils, thorns, hooks, phylloclade, tuberous stems and bulbils. Tendrils Some weak stemmed plants produce wiry, coiled, sensitive and delicate organs for climbing. They are called tendrils . These may develop from either the axillary bud or the terminal bud of the stem. In Passiflora, the tendrils develop from the axillary bud. In Cissus quadrangularis. And in Vitis vinifera the terminal bud develops into tendrils. Thorns These are hard, woody, pointed structures meant for protection. They are provided with vascular tissue, which may develop from the axillary bud or terminal buds. They control transpiration by reducing the vegetative growth. In Bougainvillae, Punica granatum and Duranta the axillary bud develop into thorns. In Duranta, the thorns are provided with leaves and flowers. In Punica granatum, the thorns bear leaves and branches. In Carissa carundus the terminal bud produces a pair of thorns. They help in protection.
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Answers:Tubers are various types of modified plant structures that are enlarged to store nutrients. They are used by plants to overwinter and regrow the next year and as a means of asexual reproduction
Answers:Sweet potato fries. Season with hot mustard, lime juice, black pepper,salt and chilli powder.
Answers:Sweet potato - also called as yam. it can be eaten by just boiling and peel it after boiling. it is smoother than potato tuber. yummier too compared to potato tuber. Potato Tuber - it is a vegetable that was used in cooking foods, French fries or fried potato.
Answers:Pumpkins are dicot, their leaves are prickly as a 'defense mechanism' to ward of any creature that might want to eat the fruit. They tend to grow and extend, the roots grow into whatever surface it can and has vines that coil around surrounding environment. ( i know this because we have pumpkins growing in the backyard and the roots are wrapped around our porch swing) You could draw a close up of a pumpkin leaf, and the way the roots grow. Here are some other fun facts that might help: Bulbs In some monocots, leaf bases grow to form bulbs, underground organs used for food storage. They can be identified from the series of leaf bases fitting inside each other, with a central shoot apical meristem. Stem Tubers In some dicotyledon plants, stems grow downwards into the soil and sections of them grow into stem tubers, also used for food storage. They are identified as their vascular bundles are arranged in rings reminiscent of stem bundles. Storage Roots These roots are swollen with stores of food, identified by the central location of vascular tissue. Tendrils These narrow outgrowths from leaves rotate through the air until they touch a solid support to which they attach, allowing the plant to climb upward