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Lithops Olivacea - Oxford Botanical Garden
''Lithops'' is a genus of succulent plants in the ice plant family, Aizoaceae. Members of the genus are native to southern Africa. They avoid being eaten by herbivores with their camouflage as small stones, and are often known as pebble plants or living stones. "Lithops" is both the genus name and the common name, and is singular as well as plural. The name is derived from the Ancient Greek words () 'stone' and () 'face', referring to the stone-like appearance of the plants. Description Individual ''Lithops'' consist of one or more pairs of bulbous, almost fused leaves opposite each other and hardly any stem. The slit between the leaves contains the meristem and produces flowers and new leaves. The leaves of ''Lithops'' are mostly buried below the surface of the soil, with a partially or completely translucent top surface known as a leaf window which allows light to enter the interior of the leaves for photosynthesis. During winter a new leaf pair, or occasionally more th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rudolf Marloth
Hermann Wilhelm Rudolf Marloth (28 December 1855 Lübben, Germany – 15 May 1931 Caledon, Cape Province) was a German-born South African botanist, pharmacist and analytical chemist, best known for his ''Flora of South Africa'' which appeared in six superbly illustrated volumes between 1913 and 1932. This botanist is denoted by the author abbreviation when citing a botanical name. Biography Early life Marloth studied pharmacy in Lübben from 1873-1876. after which he worked at various pharmacies in Germany and Switzerland, then formally qualified as a pharmacist at the University of Berlin. In 1883 he was awarded a doctorate for his thesis "''The protective mechanisms employed by seeds against harmful agents''". He arrived in Cape Town on 30 December 1883 after being urged to do so by a schoolfriend who had already settled there. During his first year there he worked as a pharmacist for the firm of Wentzel and Schleswig. He was enthralled by Cape Town and Table Mountain and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drought
A drought is a period of drier-than-normal conditions.Douville, H., K. Raghavan, J. Renwick, R.P. Allan, P.A. Arias, M. Barlow, R. Cerezo-Mota, A. Cherchi, T.Y. Gan, J. Gergis, D. Jiang, A. Khan, W. Pokam Mba, D. Rosenfeld, J. Tierney, and O. Zolina, 2021Water Cycle Changes. In Climate Change 2021: The Physical Science Basis. Contribution of Working Group I to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change [Masson-Delmotte, V., P. Zhai, A. Pirani, S.L. Connors, C. Péan, S. Berger, N. Caud, Y. Chen, L. Goldfarb, M.I. Gomis, M. Huang, K. Leitzell, E. Lonnoy, J.B.R. Matthews, T.K. Maycock, T. Waterfield, O. Yelekçi, R. Yu, and B. Zhou (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, pp. 1055–1210, doi:10.1017/9781009157896.010. A drought can last for days, months or years. Drought often has large impacts on the ecosystems and agriculture of affected regions, and causes harm to the local economy. Annua ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seed
In botany, a seed is a plant structure containing an embryo and stored nutrients in a protective coat called a ''testa''. More generally, the term "seed" means anything that can be Sowing, sown, which may include seed and husk or tuber. Seeds are the product of the ripened ovule, after the embryo sac is fertilization, fertilized by Pollen, sperm from pollen, forming a zygote. The embryo within a seed develops from the zygote and grows within the mother plant to a certain size before growth is halted. The formation of the seed is the defining part of the process of reproduction in seed plants (spermatophytes). Other plants such as ferns, mosses and marchantiophyta, liverworts, do not have seeds and use water-dependent means to propagate themselves. Seed plants now dominate biological Ecological niche, niches on land, from forests to grasslands both in hot and cold climates. In the flowering plants, the ovary ripens into a fruit which contains the seed and serves to disseminate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Capsule (fruit)
In botany, a capsule is a type of simple, dry, though rarely fleshy dehiscent fruit produced by many species of angiosperms ( flowering plants). Origins and structure The capsule (Latin: ''capsula'', small box) is derived from a compound (multicarpellary) ovary. 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. Dehiscence 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mesemb
The Aizoaceae (), or fig-marigold family, is a large Family (biology), family of dicotyledonous flowering plants containing 135 genus, genera and about 1,800 species. Several genera are commonly known as 'ice plants' or 'carpet weeds'. The Aizoaceae are also referred to as ''vygies'' in South Africa. Some of the unusual Southern African genera—such as ''Conophytum'', ''Lithops'', ''Titanopsis'' and ''Pleiospilos'' (among others)—resemble gemstones, rocks or pebbles, and are sometimes referred to as 'living stones' or 'mesembs' (short for mesembryanthemums). Description The family Aizoaceae is widely recognised by taxonomists. It once went by the botanical name "Ficoidaceae", now disallowed. The APG II system of 2003 (unchanged from the APG system of 1998) also recognizes the family, and assigns it to the order Caryophyllales in the clade core eudicots. The APG II system also classes the former families Mesembryanthemaceae Fenzl, Sesuviaceae Horan. and Tetragoniaceae Link ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pollination
Pollination is the transfer of pollen from an anther of a plant to the stigma (botany), stigma of a plant, later enabling fertilisation and the production of seeds. Pollinating agents can be animals such as insects, for example bees, beetles or butterflies; birds, and bats; water; wind; and even plants themselves. Pollinating animals travel from plant to plant carrying pollen on their bodies in a vital interaction that allows the transfer of genetic material critical to the reproductive system of most flowering plants. Self-pollination occurs within a closed flower. Pollination often occurs within a species. When pollination occurs between species, it can produce hybrid (biology), hybrid offspring in nature and in plant breeding work. In angiosperms, after the pollen grain (gametophyte) has landed on the stigma (botany), stigma, it germinates and develops a pollen tube which grows down the style (botany), style until it reaches an ovary (botany), ovary. Its two gametes travel down ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Outcrossing
Out-crossing or out-breeding is the technique of crossing between different breeds. This is the practice of introducing distantly related genetic material into a breeding line, thereby increasing genetic diversity. Outcrossing in animals Outcrossing can be a useful technique in animal breeding. The outcrossing breeder intends to remove the traits by using "new blood." With dominant traits, one can still see the expression of the traits and can remove those traits, whether one outcrosses, line breeds or inbreeds. With recessive traits, outcrossing allows for the recessive traits to migrate across a population. Many traits are Mendelian and therefore exhibit a more complicated intermediate phenotype. The outcrossing breeder then may have individuals that have many deleterious genes that may be expressed by subsequent inbreeding. There is now a gamut of deleterious genes within each individual in many dog breeds. Increasing the variation of genes or alleles within the gene poo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transparency And Translucency
In the field of optics, transparency (also called pellucidity or diaphaneity) is the physical property of allowing light to pass through the material without appreciable scattering of light. On a macroscopic scale (one in which the dimensions are much larger than the wavelengths of the photons in question), the photons can be said to follow Snell's law. Translucency (also called translucence or translucidity) is the physical property of allowing light to pass through the material (with or without scattering of light). It allows light to pass through but the light does not necessarily follow Snell's law on the macroscopic scale; the photons may be scattered at either of the two interfaces, or internally, where there is a change in the index of refraction. In other words, a translucent material is made up of components with different indices of refraction. A transparent material is made up of components with a uniform index of refraction. Transparent materials appear clear, with t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Camouflage In Plants
In evolutionary biology, mimicry in plants is where a plant evolves to resemble another organism physically or chemically. Mimicry in plants has been studied far less than mimicry in animals. It may provide protection against herbivory, or may deceptively encourage mutualists, like pollinators, to provide a service without offering a reward in return. Types of plant mimicry include Bakerian, where female flowers imitate males of the same species; Dodsonian, where a plant mimics a rewarding flower, luring pollinators by mimicking another species of flower, or fruit where feeders of the other species are attracted to a fake fruit to distribute seeds; Gilbertian, where a plant has structures like butterfly eggs, dissuading egg-laying; Vavilovian, where a weed is unintentionally selected to resemble a crop plant; Pouyannian, in which a flower imitates a female mate, deceiving a male pollinating insect into pseudocopulation; Batesian, where a harmless species deter predators by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leaf Window
Leaf window, also known as epidermal window, and fenestration, is a specialized leaf structure consisting of a translucent area through which light can enter the interior surfaces of the leaf where photosynthesis can occur. The translucent structure may include epidermal tissue, and in some succulent plants it consists of several cell layers of parenchyma, which may also function as water-storage tissue. It can appear as a large continuous patch, a variegated or reticulated region, or as numerous small spots. It is found in some succulent plants native to arid climates, allowing much of the plant to remain beneath the soil surface where it is protected from desiccation by winds and heat while optimizing light absorption. Many species featuring leaf windows are native to Southern Africa. Functions The primary function of the translucent windows is to increase the absorption of radiant energy, and thereby the rate of photosynthesis. Epidermal windows are commonly situated at the ape ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adaptation
In biology, adaptation has three related meanings. Firstly, it is the dynamic evolutionary process of natural selection that fits organisms to their environment, enhancing their evolutionary fitness. Secondly, it is a state reached by the population during that process. Thirdly, it is a phenotypic trait or adaptive trait, with a functional role in each individual organism, that is maintained and has evolved through natural selection. Historically, adaptation has been described from the time of the ancient Greek philosophers such as Empedocles and Aristotle. In 18th and 19th-century natural theology, adaptation was taken as evidence for the existence of a deity. Charles Darwin and Alfred Russel Wallace proposed instead that it was explained by natural selection. Adaptation is related to biological fitness, which governs the rate of evolution as measured by changes in allele frequencies. Often, two or more species co-adapt and co-evolve as they develop adaptations tha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dissected Lithops 0133 (3137859955)(cropped)
Dissection (from Latin ' "to cut to pieces"; also called anatomization) is the dismembering of the body of a deceased animal or plant to study its anatomical structure. Autopsy is used in pathology and forensic medicine to determine the cause of death in humans. Less extensive dissection of plants and smaller animals preserved in a formaldehyde solution is typically carried out or demonstrated in biology and natural science classes in middle school and high school, while extensive dissections of cadavers of adults and children, both fresh and preserved are carried out by medical students in medical schools as a part of the teaching in subjects such as anatomy, pathology and forensic medicine. Consequently, dissection is typically conducted in a morgue or in an anatomy lab. Dissection has been used for centuries to explore anatomy. Objections to the use of cadavers have led to the use of alternatives including virtual dissection of computer models. In the field of surgery, the t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
