Which of the following statement is true? Haversian canal in the bone of mammals are connected by small blood vessel canal called. If a biochemical analysis of mitochondria has to be done, the best procedure would be. Choose the correct statement. Match the following column I with column II.
What is true of urea biosynthesis? Biology Most Viewed Questions. Match the following columns and select the correct option. Research published in revealed that one Philippine Rafflesia species from the island of Luzon , R. Rafflesia can be found along the area of Peninsular Malaysia and Thailand in Malay peninsula. In Perak, three species of the flower can be found in Royal Belum state park and Gerik forest reserve of which are Rafflesia kerrii , Rafflesia cantleyi and Rafflesia azlanii.
A flower has been found in this area hanging on the root of its host three metres above the ground, unlike the common flowers found on the ground roots. The locations of these flowers are turned into tourist attractions for biodiversity lovers and hikers and helps to generate income for the local people. In Thailand Rafflesia can be observed in Khao Sok National Park where the flowers are numbered and monitored by the park rangers.
Species native to Borneo include Rafflesia arnoldii , R. The flower size is between 60 cm to 80 cm. Due to its size, the flower is generally found on the forest floor growing on the underground stem or root of Tetrastigma lanceolarium. The Mindanao species is known as Rafflesia schadenbergiana , after the naturalist Alexander Schadenberg , who first discovered the species at the foothills of Mount Apo in With a flower of nearly a meter, it is close to the size of a seated child.
The two forms differ in size measurements in which the scientific description of R. The medium-sized R. It shows a combination of three features of Philippine Rafflesia , namely: the shape and size of the conical process in R.
Species of Rafflesia are all thought to be holoparasites of lianas of the genus Tetrastigma , vines which belong to the Vitaceae , the family of the grape vines. They are thus, in a way, hyperparasites , because Tetrastigma are themselves, in a way, structural parasites of the trees they use to climb up to the light.
Rafflesia appear to be species-specific, with each Rafflesia species naturally only growing on one to three species of Tetrastigma. Of the 57 known species of Tetrastigma , only ten are known to be host plants. Of the 30 odd species of Rafflesia , the host plants are only known from about half of the species.
Strangely, a certain species of Tetrastigma is very popular among Rafflesia , T. The flowers may bud from different locations, R. The gender ratio may be skewed. This may not matter: female flowers usually form fruit anyway and may thus be agamospermous. In Rafflesia arnoldii the flowers are visited by the flies Drosophila colorata , Chrysomya megacephala and Sarcophaga haemorrhoidalis. Black ants of the genus Euprenolepis may feed on the developing flower buds, perhaps killing them.
Mammals which have been recorded destroying the buds or flowers, often simply by stepping on and crushing them, are: pigs Sus scrofa , wild cats Felis bengalensis , rusa Cervus timorensis , muntjak Muntiacus muntjak and banteng Bos javanicus.
In Thailand the buds and flowers of R. They are also harvested for herbalism , a concoction is believed to act as a sexual stimulant and to help for fever or backache. It is unknown for what the buds are supposed to be good for; [43] jamu concoctions are often complex mixtures and often are supposed to help with sexual prowess.
These plants also have some economic use in attracting ecotourists. Research in Malaysia and Indonesia has made it possible to propagate the species for use in horticulture, with the famous Bogor Botanical Garden growing the first plants in the s using grafts of infected vines. The Malaysian biologist Jamili Nais was the first to propagate the plants using the seeds around the year The first British person to see one was Joseph Arnold in , in the Indonesia rainforest in Bengkulu, Sumatra , after a Malay servant working for him discovered a flower and pointed it out to him.
It was later named after Stamford Raffles , the leader of the expedition. Creatures » … » Plants » … » Rafflesias. Biology provided by Arkive. The enormous Rafflesia flowers are believed to be pollinated by flies; alighting on the central disk flies crawl underneath it where they come into contact with the sexual organs 2. It has been reported that the flowers have a strong smell of rotting flesh but it is unclear whether this acts to attract flies or is merely a by-product of the decaying petals, which reduce into a black slimy mess after around 4 days 2.
Conservation provided by Arkive. Rafflesia species are protected in a number of reserves within their range such as Mount Kinabalu National Park in Sabah on the island of Borneo 5. Habitat protection is one of the key factors in securing the future of this species and this magnificent flower is a huge draw to tourists, bringing much needed revenue to the area. More investigation into the life cycle of this unusual species is urgently needed to enable propagation and ex-situ conservation measures 3.
Recent success in propagating R. Description provided by Arkive. The dramatic Rafflesia flowers are the largest single flowers in the world; the leathery petals can reach over 90 centimetres across 2. Rafflesia is a parasite that depends completely upon its host; the majority of the plant's tissues exist as thread-like strands entirely within the host's cells 3.
These host plants are vines of Tetrastigma spp. The flowers can take up to 10 months to develop from the first visible bud to the open bloom, which may last no more than a few days 5. Currently 17 species of Rafflesia are recognised and these mainly differ in the morphology of their flowers 4. In general however, the flowers consist of 5 leathery petals that are orange in colour and mottled with cream-coloured warts 2. There is a deep well in the centre of the flower containing a central raised disc raised that supports many vertical spines 2.
The sexual organs are located beneath the rim of the disk, and male and female flowers are separate 2. Habitat provided by Arkive.
Rafflesia plants are specialist parasites only found in association with specific species of the host vine Tetrastigma spp. These vines are found in both primary and secondary rainforest 4. Range provided by Arkive. The genus as a whole is considered to be rare although information on distribution is lacking due to the difficulties of identifying plants within their host vines 4.
Status provided by Arkive. Threats provided by Arkive. Rafflesia are inherently rare as a result of a number of factors of their life cycle; they have a double habitat specialisation, as they can only successfully parasitise particular species and these species in turn are found only in specific habitats 4.
In addition to this factor, there is an extremely unbalanced sex ratio in the Rafflesia flowers observed, with many more male than female flowers 4. In addition to these inherent factors, there is widespread habitat destruction within much of the rainforested area of Southeast Asia and Rafflesia buds are also collected for traditional medicine, to treat fertility problems, in parts of their range 5.
Rafflesia provided by wikipedia EN. Arnold was quite excited when he saw his first flower, the following is from his account: [4] "Here I rejoice to tell you I happened to meet with what I consider as the greatest prodigy of the vegetable world.
Mat-Salleh, Khairil, Zuhailah, Mohd. Adam, R. These species are highly specific as to the hosts that they parasitize, preferring only a few species of Tetrastigma a member of the common grape family that are distributed in the same geographic area. Although technically a member of the plant kingdom, Rafflesia challenges traditional definitions of what a plant is because they lack chlorophyll and are therefore incapable of photosynthesis as are all members of its family, Rafflesiaceae.
While many parasites appear like normal plants, Rafflesia lacks any observable leaves, roots, or even stems Meijer, Likened to fungi, Rafflesia individuals grow as thread-like strands of tissue completely embedded within and in intimate contact with surrounding host cells from which nutrients and water are obtained Mat Salleh, Perhaps the only part of Rafflesia that is identifiable as distinctly plant-like are the flowers; however, even these are bizarre because they attain massive proportions up to 3 ft in diameter and are usually reddish-brown and stink of rotting flesh..
Although parasitic, Rafflesia species do not typically kill their hosts in spite of the drain on resources that they cause. Pollination in Rafflesia has been studied Beaman et al.
0コメント