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Ginkgo biloba : 

Ginkgo biloba Scientific classification Kingdom : PlantaeDivision : GinkgophytaClass : GinkgoopsidaOrder : GinkgoalesFamily : GinkgoaceaeGenus : GinkgoSpecies : GinKgo biloba

Distribution and habitat : 

Distribution and habitat Although Ginkgo biloba and other species of the genus were once widespread throughout the world The tree currently occurs in the wild only in the northwest of Zhejiang province in the Tianmu Shan mountain reserve in eastern China In other areas of China it has been long cultivated and it is common in the southern third of the country.

Cont.. : 

Cont.. It has also been commonly cultivated in North America for over 200 years, but during that time it has never become significantly naturalised. Where it occurs in the wild it is found infrequently in deciduous forests and valleys on acidic loess (i.e. fine, silty soil) with good drainage. The soil it inhabits is typically in the pH range of 5 to 5.5

Description : 

Description Ginkgos are very large trees, normally reaching a height of 20–35 m with some specimens in China being over 50 m (164 feet). During autumn, the leaves turn a bright yellow, then fall, sometimes within a short space of time (1–15 days). ginkgos long-lived, with some specimens claimed to be more than 2,500 years old.

Leaves : 

Leaves The leaves are usually 5-10 cm (2-4 inches), but sometimes up to 15 cm (6 inches) long. The leaves are unique among seed plants, being fan-shaped with veins radiating out into the leaf blade,  Two veins enter the leaf blade at the base and fork repeatedly in two, this is known as dichotomous venation.

Seed : 

Seed Ginkgo is classified as a gymnosperm translated as ”naked seed”  Ginkgo seeds about 2.5 cms. in length. This Biloba ginkgo seed consist of a large “nut” as large as almond surrounded by a fleshy outer layer.

Stem : 

Stem Ginkgo branches grow in length by growth of shoots with regularly spaced leaves From the axils of these leaves, "spur shoots" (also known as short shoots) develop on second-year growth. Short shoots have very short internodes  and their leaves are usually unlobed.

Flower : 


Slide 11: 

ation ginkgo ovules and leaves Ovules ready for fertilization Autumn leaves and fallen seeds Ginkgo-bearing cones

Paleontology : 

Paleontology The Ginkgo is a living fossil, with fossils recognisably related to modern Ginkgo from the Permian Dating back 270 million years. Fossils attributable to the genus Ginkgo first appeared in the Early Jurassic, and the genus diversified and spread throughout Laurasia during the middle Jurassic and Early Cretaceous Ginkgo biloba Eocene leaf from the MacAbee, B.C., Canada. Fossil Ginkgo leaves from the Jurassic of England

Taxonomy and naming : 

Taxonomy and naming The species was initially described by the father of taxonomy Linnaeus in 1771, the specific epithet biloba derived from the Latin bis 'two' and loba 'lobed', referring to the shape of the leaves

Medicinal uses : 

Medicinal uses Extracts of Ginkgo leaves contain flavonoid glycosides and terpenoids and have been used pharmaceutically.   Ginkgo supplements are usually taken in the range of 40–200 mg per day. Recently, careful clinical trials have shown Ginkgo to be ineffective in treating dementia or preventing the onset of Alzheimer's Disease in normal people.

Culinary use : 

Culinary use The nut-like gametophytes inside the seeds are particularly esteemed in Asia, and are a traditional Chinese food. Japanese cooks add Ginkgo seeds (called ginnan) to dishes such as chawanmushi, and cooked seeds are often eaten along with other dishes.

Side effects : 

Side effects Ginkgo may have undesirable effects, especially for individuals with blood circulation disorders and those taking anticoagulants  such as ibuprofen, aspirin, or warfarin, although recent studies have found that ginkgo has little or no effect on the anticoagulant properties or pharmacodynamics of warfarin. Ginkgo should also not be used by people who are taking certain types of antidepressants (monoamine oxidase inhibitors and selective serotonin reuptake inhibitors) or by pregnant women, without first consulting a doctor.

References : 

References "Ginkgo biloba 'Autumn Gold‘ History of Discovery of Spermatozoids In Ginkgo biloba and Cycas revoluta  IUCN Red List of Threatened Species. IUCN  www.iucnredlist.org

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