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91-647: Locals refer to the Kitulo Plateau as "Bustani ya Mungu" ("The Garden of God"), while botanists have referred to it as the "Serengeti of Flowers". Protection of the Kitulo Plateau's unique flora was first proposed by the Wildlife Conservation Society (WCS), in response to the growing international trade in orchid tubers and increased hunting and logging activities in the surrounding forests. In 2002, President Benjamin Mkapa announced

182-442: A woody stem ), grasses and grass-like plants, a vast majority of broad-leaved trees , shrubs and vines , and most aquatic plants . Angiosperms are distinguished from the other major seed plant clade, the gymnosperms , by having flowers , xylem consisting of vessel elements instead of tracheids , endosperm within their seeds, and fruits that completely envelop the seeds. The ancestors of flowering plants diverged from

273-490: A botanically and pharmacologically important herbal Historia Plantarum in 1544 and a pharmacopoeia of lasting importance, the Dispensatorium in 1546. Naturalist Conrad von Gesner (1516–1565) and herbalist John Gerard (1545– c.  1611 ) published herbals covering the supposed medicinal uses of plants. Naturalist Ulisse Aldrovandi (1522–1605) was considered the father of natural history , which included

364-414: A considerable problem in agriculture, and the biology and control of plant pathogens in agriculture and natural ecosystems . Ethnobotany is the study of the relationships between plants and people. When applied to the investigation of historical plant–people relationships ethnobotany may be referred to as archaeobotany or palaeoethnobotany . Some of the earliest plant-people relationships arose between

455-452: A continuum between the major morphological categories of root, stem (caulome), leaf (phyllome) and trichome . Furthermore, it emphasises structural dynamics. Modern systematics aims to reflect and discover phylogenetic relationships between plants. Modern Molecular phylogenetics largely ignores morphological characters, relying on DNA sequences as data. Molecular analysis of DNA sequences from most families of flowering plants enabled

546-400: A hierarchical classification of plant species that remains the reference point for modern botanical nomenclature . This established a standardised binomial or two-part naming scheme where the first name represented the genus and the second identified the species within the genus. For the purposes of identification, Linnaeus's Systema Sexuale classified plants into 24 groups according to

637-404: A plant sucks water through them under water stress. Lignin is also used in other cell types like sclerenchyma fibres that provide structural support for a plant and is a major constituent of wood. Sporopollenin is a chemically resistant polymer found in the outer cell walls of spores and pollen of land plants responsible for the survival of early land plant spores and the pollen of seed plants in

728-552: A polymer of fructose is used for the same purpose in the sunflower family Asteraceae . Some of the glucose is converted to sucrose (common table sugar) for export to the rest of the plant. Unlike in animals (which lack chloroplasts), plants and their eukaryote relatives have delegated many biochemical roles to their chloroplasts , including synthesising all their fatty acids , and most amino acids . The fatty acids that chloroplasts make are used for many things, such as providing material to build cell membranes out of and making

819-464: A process that generates molecular oxygen (O 2 ) as a by-product. The light energy captured by chlorophyll a is initially in the form of electrons (and later a proton gradient ) that's used to make molecules of ATP and NADPH which temporarily store and transport energy. Their energy is used in the light-independent reactions of the Calvin cycle by the enzyme rubisco to produce molecules of

910-505: A pure form of carbon made by pyrolysis of wood, has a long history as a metal- smelting fuel, as a filter material and adsorbent and as an artist's material and is one of the three ingredients of gunpowder . Cellulose , the world's most abundant organic polymer, can be converted into energy, fuels, materials and chemical feedstock. Products made from cellulose include rayon and cellophane , wallpaper paste , biobutanol and gun cotton . Sugarcane , rapeseed and soy are some of

1001-536: A student of Aristotle who invented and described many of its principles and is widely regarded in the scientific community as the "Father of Botany". His major works, Enquiry into Plants and On the Causes of Plants , constitute the most important contributions to botanical science until the Middle Ages , almost seventeen centuries later. Another work from Ancient Greece that made an early impact on botany

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1092-610: A total of 64 angiosperm orders and 416 families. The diversity of flowering plants is not evenly distributed. Nearly all species belong to the eudicot (75%), monocot (23%), and magnoliid (2%) clades. The remaining five clades contain a little over 250 species in total; i.e. less than 0.1% of flowering plant diversity, divided among nine families. The 25 most species-rich of 443 families, containing over 166,000 species between them in their APG circumscriptions, are: The botanical term "angiosperm", from Greek words angeíon ( ἀγγεῖον 'bottle, vessel') and spérma ( σπέρμα 'seed'),

1183-460: A useful proxy for temperature in historical climatology , and the biological impact of climate change and global warming . Palynology , the analysis of fossil pollen deposits in sediments from thousands or millions of years ago allows the reconstruction of past climates. Estimates of atmospheric CO 2 concentrations since the Palaeozoic have been obtained from stomatal densities and

1274-1010: A variety of spatial scales in groups, populations and communities that collectively constitute vegetation. Regions with characteristic vegetation types and dominant plants as well as similar abiotic and biotic factors, climate , and geography make up biomes like tundra or tropical rainforest . Herbivores eat plants, but plants can defend themselves and some species are parasitic or even carnivorous . Other organisms form mutually beneficial relationships with plants. For example, mycorrhizal fungi and rhizobia provide plants with nutrients in exchange for food, ants are recruited by ant plants to provide protection, honey bees , bats and other animals pollinate flowers and humans and other animals act as dispersal vectors to spread spores and seeds . Plant responses to climate and other environmental changes can inform our understanding of how these changes affect ecosystem function and productivity. For example, plant phenology can be

1365-628: A way of drug discovery . Plants can synthesise coloured dyes and pigments such as the anthocyanins responsible for the red colour of red wine , yellow weld and blue woad used together to produce Lincoln green , indoxyl , source of the blue dye indigo traditionally used to dye denim and the artist's pigments gamboge and rose madder . Sugar, starch , cotton, linen , hemp , some types of rope , wood and particle boards , papyrus and paper, vegetable oils , wax , and natural rubber are examples of commercially important materials made from plant tissues or their secondary products. Charcoal ,

1456-456: A wider range of shared characters and were widely followed. The Candollean system reflected his ideas of the progression of morphological complexity and the later Bentham & Hooker system , which was influential until the mid-19th century, was influenced by Candolle's approach. Darwin 's publication of the Origin of Species in 1859 and his concept of common descent required modifications to

1547-406: Is De materia medica , a five-volume encyclopedia about preliminary herbal medicine written in the middle of the first century by Greek physician and pharmacologist Pedanius Dioscorides . De materia medica was widely read for more than 1,500 years. Important contributions from the medieval Muslim world include Ibn Wahshiyya 's Nabatean Agriculture , Abū Ḥanīfa Dīnawarī 's (828–896)

1638-405: Is peppermint , Mentha × piperita , a sterile hybrid between Mentha aquatica and spearmint, Mentha spicata . The many cultivated varieties of wheat are the result of multiple inter- and intra- specific crosses between wild species and their hybrids. Angiosperms with monoecious flowers often have self-incompatibility mechanisms that operate between the pollen and stigma so that

1729-858: Is starting to impact plants and is likely to cause many species to become extinct by 2100. Angiosperms are terrestrial vascular plants; like the gymnosperms, they have roots , stems , leaves , and seeds . They differ from other seed plants in several ways. The largest angiosperms are Eucalyptus gum trees of Australia, and Shorea faguetiana , dipterocarp rainforest trees of Southeast Asia, both of which can reach almost 100 metres (330 ft) in height. The smallest are Wolffia duckweeds which float on freshwater, each plant less than 2 millimetres (0.08 in) across. Considering their method of obtaining energy, some 99% of flowering plants are photosynthetic autotrophs , deriving their energy from sunlight and using it to create molecules such as sugars . The remainder are parasitic , whether on fungi like

1820-762: Is gathered by ethnobotanists. This information can relay a great deal of information on how the land once was thousands of years ago and how it has changed over that time. The goals of plant ecology are to understand the causes of their distribution patterns, productivity, environmental impact, evolution, and responses to environmental change. Plants depend on certain edaphic (soil) and climatic factors in their environment but can modify these factors too. For example, they can change their environment's albedo , increase runoff interception, stabilise mineral soils and develop their organic content, and affect local temperature. Plants compete with other organisms in their ecosystem for resources. They interact with their neighbours at

1911-451: Is still a major foundation of modern botany. Her books Plant Anatomy and Anatomy of Seed Plants have been key plant structural biology texts for more than half a century. The discipline of plant ecology was pioneered in the late 19th century by botanists such as Eugenius Warming , who produced the hypothesis that plants form communities , and his mentor and successor Christen C. Raunkiær whose system for describing plant life forms

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2002-400: Is still given to these groups by botanists, and fungi (including lichens) and photosynthetic protists are usually covered in introductory botany courses. Palaeobotanists study ancient plants in the fossil record to provide information about the evolutionary history of plants . Cyanobacteria , the first oxygen-releasing photosynthetic organisms on Earth, are thought to have given rise to

2093-444: Is still in use today. The concept that the composition of plant communities such as temperate broadleaf forest changes by a process of ecological succession was developed by Henry Chandler Cowles , Arthur Tansley and Frederic Clements . Clements is credited with the idea of climax vegetation as the most complex vegetation that an environment can support and Tansley introduced the concept of ecosystems to biology. Building on

2184-513: Is the largest block of forest in the park, and the largest in the Kipengere Range. Thickets of bamboo ( Yushania alpina ) can be found between the upper montane forests and the high altitude grasslands. The Livingstone Forest lies in the former Livingstone Forest Reserve (240.34 km²), which was incorporated into the national park when it was created in 2005. The Bujingijila Gap, a narrow corridor of farms and tree plantations, separates

2275-498: Is the study of ferns and allied plants. A number of other taxa of ranks varying from family to subgenus have terms for their study, including agrostology (or graminology) for the study of grasses, synantherology for the study of composites, and batology for the study of brambles. Study can also be divided by guild rather than clade or grade . Dendrology is the study of woody plants. Many divisions of biology have botanical subfields. These are commonly denoted by prefixing

2366-491: The Alismatales grow in marine environments, spreading with rhizomes that grow through the mud in sheltered coastal waters. Some specialised angiosperms are able to flourish in extremely acid or alkaline habitats. The sundews , many of which live in nutrient-poor acid bogs , are carnivorous plants , able to derive nutrients such as nitrate from the bodies of trapped insects. Other flowers such as Gentiana verna ,

2457-466: The Ancient Greek word botanē ( βοτάνη ) meaning " pasture ", " herbs " " grass ", or " fodder "; Botanē is in turn derived from boskein ( Greek : βόσκειν ), "to feed" or "to graze ". Traditionally, botany has also included the study of fungi and algae by mycologists and phycologists respectively, with the study of these three groups of organisms remaining within

2548-564: The Angiosperm Phylogeny Group to publish in 1998 a phylogeny of flowering plants, answering many of the questions about relationships among angiosperm families and species. The theoretical possibility of a practical method for identification of plant species and commercial varieties by DNA barcoding is the subject of active current research. Botany is divided along several axes. Some subfields of botany relate to particular groups of organisms. Divisions related to

2639-499: The Book of Plants , and Ibn Bassal 's The Classification of Soils . In the early 13th century, Abu al-Abbas al-Nabati , and Ibn al-Baitar (d. 1248) wrote on botany in a systematic and scientific manner. In the mid-16th century, botanical gardens were founded in a number of Italian universities. The Padua botanical garden in 1545 is usually considered to be the first which is still in its original location. These gardens continued

2730-417: The C 4 carbon fixation pathway for photosynthesis which avoid the losses resulting from photorespiration in the more common C 3 carbon fixation pathway. These biochemical strategies are unique to land plants. Phytochemistry is a branch of plant biochemistry primarily concerned with the chemical substances produced by plants during secondary metabolism . Some of these compounds are toxins such as

2821-504: The alkaloid coniine from hemlock . Others, such as the essential oils peppermint oil and lemon oil are useful for their aroma, as flavourings and spices (e.g., capsaicin ), and in medicine as pharmaceuticals as in opium from opium poppies . Many medicinal and recreational drugs , such as tetrahydrocannabinol (active ingredient in cannabis ), caffeine , morphine and nicotine come directly from plants. Others are simple derivatives of botanical natural products. For example,

Kitulo National Park - Misplaced Pages Continue

2912-565: The auxin plant hormones by Kenneth V. Thimann in 1948 enabled regulation of plant growth by externally applied chemicals. Frederick Campion Steward pioneered techniques of micropropagation and plant tissue culture controlled by plant hormones . The synthetic auxin 2,4-dichlorophenoxyacetic acid or 2,4-D was one of the first commercial synthetic herbicides . 20th century developments in plant biochemistry have been driven by modern techniques of organic chemical analysis , such as spectroscopy , chromatography and electrophoresis . With

3003-626: The cell theory with Theodor Schwann and Rudolf Virchow and was among the first to grasp the significance of the cell nucleus that had been described by Robert Brown in 1831. In 1855, Adolf Fick formulated Fick's laws that enabled the calculation of the rates of molecular diffusion in biological systems. Building upon the gene-chromosome theory of heredity that originated with Gregor Mendel (1822–1884), August Weismann (1834–1914) proved that inheritance only takes place through gametes . No other cells can pass on inherited characters. The work of Katherine Esau (1898–1997) on plant anatomy

3094-444: The cellulose and lignin used to build their bodies, and secondary products like resins and aroma compounds . Plants and various other groups of photosynthetic eukaryotes collectively known as " algae " have unique organelles known as chloroplasts . Chloroplasts are thought to be descended from cyanobacteria that formed endosymbiotic relationships with ancient plant and algal ancestors. Chloroplasts and cyanobacteria contain

3185-584: The clade Angiospermae ( / ˌ æ n dʒ i ə ˈ s p ər m iː / ). The term 'angiosperm' is derived from the Greek words ἀγγεῖον / angeion ('container, vessel') and σπέρμα / sperma ('seed'), meaning that the seeds are enclosed within a fruit. The group was formerly called Magnoliophyta . Angiosperms are by far the most diverse group of land plants with 64 orders , 416 families , approximately 13,000 known genera and 300,000 known species . They include all forbs (flowering plants without

3276-427: The indigenous people of Canada in identifying edible plants from inedible plants. This relationship the indigenous people had with plants was recorded by ethnobotanists. Plant biochemistry is the study of the chemical processes used by plants. Some of these processes are used in their primary metabolism like the photosynthetic Calvin cycle and crassulacean acid metabolism . Others make specialised materials like

3367-460: The orchids for part or all of their life-cycle, or on other plants , either wholly like the broomrapes, Orobanche , or partially like the witchweeds, Striga . In terms of their environment, flowering plants are cosmopolitan, occupying a wide range of habitats on land, in fresh water and in the sea. On land, they are the dominant plant group in every habitat except for frigid moss-lichen tundra and coniferous forest . The seagrasses in

3458-426: The pines , and flowering plants ) and the free-sporing cryptogams including ferns , clubmosses , liverworts , hornworts and mosses . Embryophytes are multicellular eukaryotes descended from an ancestor that obtained its energy from sunlight by photosynthesis . They have life cycles with alternating haploid and diploid phases. The sexual haploid phase of embryophytes, known as the gametophyte , nurtures

3549-892: The "Big Five" extinction events in Earth's history, only the Cretaceous–Paleogene extinction event had occurred while angiosperms dominated plant life on the planet. Today, the Holocene extinction affects all kingdoms of complex life on Earth, and conservation measures are necessary to protect plants in their habitats in the wild ( in situ ), or failing that, ex situ in seed banks or artificial habitats like botanic gardens . Otherwise, around 40% of plant species may become extinct due to human actions such as habitat destruction , introduction of invasive species , unsustainable logging , land clearing and overharvesting of medicinal or ornamental plants . Further, climate change

3640-408: The 3-carbon sugar glyceraldehyde 3-phosphate (G3P). Glyceraldehyde 3-phosphate is the first product of photosynthesis and the raw material from which glucose and almost all other organic molecules of biological origin are synthesised. Some of the glucose is converted to starch which is stored in the chloroplast. Starch is the characteristic energy store of most land plants and algae, while inulin ,

3731-517: The Candollean system to reflect evolutionary relationships as distinct from mere morphological similarity. Botany was greatly stimulated by the appearance of the first "modern" textbook, Matthias Schleiden 's Grundzüge der Wissenschaftlichen Botanik , published in English in 1849 as Principles of Scientific Botany . Schleiden was a microscopist and an early plant anatomist who co-founded

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3822-543: The Livingstone Forest area of the park. Initially known as the Highland Mangabey, later changed to its Tanzanian name of Kipunji , it is one of the 25 most endangered primates in the world. The Ndumbi forest, at the eastern end of Kitulo National Park, includes montane evergreen forest and forests of East African Cedar ( Juniperus procera ). The former Ndumbi Valley Forest Reserve (27.71 km²)

3913-565: The Livingstone Forest from the Mount Rungwe forests. The Livingstone Forest is home to three limited-range species of mammals – the endangered Kipunji ( Rungwecebus kipunji ), Rungwe dwarf galago ( Galagoides sp. nov.), and Abbott's duiker ( Cephalophus spadix ). All three species also live in the forests of nearby Mount Rungwe . In 2005, field scientists from the WCS discovered a new species of primate on and around Mount Rungwe and in

4004-457: The November to April wet season the montane grasslands are carpeted with displays of flowers. Many species are limited to the Kipengere Range and nearby highlands, and three – Brachystelma kituloensis, Impatiens rosulata and Pterygodium ukingense – are limited the Kitulo Plateau. The Livingstone forest is a montane evergreen forest that descends the souttwestward-facing slope of the park. It

4095-482: The Vegetable Kingdom at the start of chapter XII noted "The first and most important of the conclusions which may be drawn from the observations given in this volume, is that generally cross-fertilisation is beneficial and self-fertilisation often injurious, at least with the plants on which I experimented." An important adaptive benefit of outcrossing is that it allows the masking of deleterious mutations in

4186-412: The above pair of categories gives rise to fields such as bryogeography (the study of the distribution of mosses). Different parts of plants also give rise to their own subfields, including xylology , carpology (or fructology) and palynology , these been the study of wood, fruit and pollen/spores respectively. Botany also overlaps on the one hand with agriculture, horticulture and silviculture, and on

4277-439: The ancestor of plants by entering into an endosymbiotic relationship with an early eukaryote, ultimately becoming the chloroplasts in plant cells. The new photosynthetic plants (along with their algal relatives) accelerated the rise in atmospheric oxygen started by the cyanobacteria , changing the ancient oxygen-free, reducing , atmosphere to one in which free oxygen has been abundant for more than 2 billion years. Among

4368-447: The base of most food chains because they use the energy from the sun and nutrients from the soil and atmosphere, converting them into a form that can be used by animals. This is what ecologists call the first trophic level . The modern forms of the major staple foods , such as hemp , teff , maize, rice, wheat and other cereal grasses, pulses , bananas and plantains, as well as hemp , flax and cotton grown for their fibres, are

4459-418: The beginnings of plant taxonomy and led in 1753 to the binomial system of nomenclature of Carl Linnaeus that remains in use to this day for the naming of all biological species. In the 19th and 20th centuries, new techniques were developed for the study of plants, including methods of optical microscopy and live cell imaging , electron microscopy , analysis of chromosome number , plant chemistry and

4550-500: The blue-green pigment chlorophyll a . Chlorophyll a (as well as its plant and green algal-specific cousin chlorophyll b ) absorbs light in the blue-violet and orange/red parts of the spectrum while reflecting and transmitting the green light that we see as the characteristic colour of these organisms. The energy in the red and blue light that these pigments absorb is used by chloroplasts to make energy-rich carbon compounds from carbon dioxide and water by oxygenic photosynthesis ,

4641-446: The broader historical sense of botany include bacteriology , mycology (or fungology) and phycology - the study of bacteria, fungi and algae respectively - with lichenology as a subfield of mycology. The narrower sense of botany in the sense of the study of embryophytes (land plants) is disambiguated as phytology. Bryology is the study of mosses (and in the broader sense also liverworts and hornworts). Pteridology (or filicology)

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4732-513: The characters may be artificial in keys designed purely for identification ( diagnostic keys ) or more closely related to the natural or phyletic order of the taxa in synoptic keys. By the 18th century, new plants for study were arriving in Europe in increasing numbers from newly discovered countries and the European colonies worldwide. In 1753, Carl Linnaeus published his Species Plantarum ,

4823-560: The common ancestor of all living gymnosperms before the end of the Carboniferous , over 300 million years ago. In the Cretaceous , angiosperms diversified explosively , becoming the dominant group of plants across the planet. Agriculture is almost entirely dependent on angiosperms, and a small number of flowering plant families supply nearly all plant-based food and livestock feed. Rice , maize and wheat provide half of

4914-461: The developing diploid embryo sporophyte within its tissues for at least part of its life, even in the seed plants, where the gametophyte itself is nurtured by its parent sporophyte. Other groups of organisms that were previously studied by botanists include bacteria (now studied in bacteriology ), fungi ( mycology ) – including lichen -forming fungi ( lichenology ), non- chlorophyte algae ( phycology ), and viruses ( virology ). However, attention

5005-430: The establishment of the park. The park was formally gazetted in 2005, becoming Tanzania's fourteenth national park. TANAPA has stated that the park could be expanded in the future to include the neighbouring Mount Rungwe forest. The Kitulo Plateau lies between two parallel ridges. Its montane grasslands are home to 350 species of plants, including numerous ground orchids, geophytes , and other Afroalpine plants. During

5096-453: The extensive earlier work of Alphonse de Candolle , Nikolai Vavilov (1887–1943) produced accounts of the biogeography , centres of origin , and evolutionary history of economic plants. Particularly since the mid-1960s there have been advances in understanding of the physics of plant physiological processes such as transpiration (the transport of water within plant tissues), the temperature dependence of rates of water evaporation from

5187-489: The first endeavours of human investigation. Medieval physic gardens , often attached to monasteries , contained plants possibly having medicinal benefit. They were forerunners of the first botanical gardens attached to universities , founded from the 1540s onwards. One of the earliest was the Padua botanical garden . These gardens facilitated the academic study of plants. Efforts to catalogue and describe their collections were

5278-580: The flowering plants as an unranked clade without a formal Latin name (angiosperms). A formal classification was published alongside the 2009 revision in which the flowering plants rank as the subclass Magnoliidae. From 1998, the Angiosperm Phylogeny Group (APG) has reclassified the angiosperms, with updates in the APG II system in 2003, the APG III system in 2009, and the APG IV system in 2016. In 2019,

5369-575: The fossil record. It is widely regarded as a marker for the start of land plant evolution during the Ordovician period. The concentration of carbon dioxide in the atmosphere today is much lower than it was when plants emerged onto land during the Ordovician and Silurian periods. Many monocots like maize and the pineapple and some dicots like the Asteraceae have since independently evolved pathways like Crassulacean acid metabolism and

5460-451: The functional relationships between plants and their habitats  – the environments where they complete their life cycles . Plant ecologists study the composition of local and regional floras , their biodiversity , genetic diversity and fitness , the adaptation of plants to their environment, and their competitive or mutualistic interactions with other species. Some ecologists even rely on empirical data from indigenous people that

5551-461: The genome of progeny. This beneficial effect is also known as hybrid vigor or heterosis. Once outcrossing is established, subsequent switching to inbreeding becomes disadvantageous since it allows expression of the previously masked deleterious recessive mutations, commonly referred to as inbreeding depression. Flowering plant Basal angiosperms Core angiosperms Flowering plants are plants that bear flowers and fruits , and form

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5642-444: The global carbon and water cycles and plant roots bind and stabilise soils, preventing soil erosion . Plants are crucial to the future of human society as they provide food, oxygen, biochemicals , and products for people, as well as creating and preserving soil. Historically, all living things were classified as either animals or plants and botany covered the study of all organisms not considered animals. Botanists examine both

5733-621: The important botanical questions of the 21st century are the role of plants as primary producers in the global cycling of life's basic ingredients: energy, carbon, oxygen, nitrogen and water, and ways that our plant stewardship can help address the global environmental issues of resource management , conservation , human food security , biologically invasive organisms , carbon sequestration , climate change , and sustainability . Virtually all staple foods come either directly from primary production by plants, or indirectly from animals that eat them. Plants and other photosynthetic organisms are at

5824-478: The internal functions and processes within plant organelles , cells, tissues, whole plants, plant populations and plant communities. At each of these levels, a botanist may be concerned with the classification ( taxonomy ), phylogeny and evolution , structure ( anatomy and morphology ), or function ( physiology ) of plant life. The strictest definition of "plant" includes only the "land plants" or embryophytes , which include seed plants (gymnosperms, including

5915-403: The leaf shapes and sizes of ancient land plants . Ozone depletion can expose plants to higher levels of ultraviolet radiation-B (UV-B), resulting in lower growth rates. Moreover, information from studies of community ecology , plant systematics , and taxonomy is essential to understanding vegetation change , habitat destruction and species extinction . Inheritance in plants follows

6006-576: The leaf surface and the molecular diffusion of water vapour and carbon dioxide through stomatal apertures. These developments, coupled with new methods for measuring the size of stomatal apertures, and the rate of photosynthesis have enabled precise description of the rates of gas exchange between plants and the atmosphere. Innovations in statistical analysis by Ronald Fisher , Frank Yates and others at Rothamsted Experimental Station facilitated rational experimental design and data analysis in botanical research. The discovery and identification of

6097-493: The major groups of organisms that carry out photosynthesis , a process that uses the energy of sunlight to convert water and carbon dioxide into sugars that can be used both as a source of chemical energy and of organic molecules that are used in the structural components of cells. As a by-product of photosynthesis, plants release oxygen into the atmosphere, a gas that is required by nearly all living things to carry out cellular respiration. In addition, they are influential in

6188-518: The manner of vines or lianas . The number of species of flowering plants is estimated to be in the range of 250,000 to 400,000. This compares to around 12,000 species of moss and 11,000 species of pteridophytes . The APG system seeks to determine the number of families , mostly by molecular phylogenetics . In the 2009 APG III there were 415 families. The 2016 APG IV added five new orders (Boraginales, Dilleniales, Icacinales, Metteniusales and Vahliales), along with some new families, for

6279-596: The number of their male sexual organs. The 24th group, Cryptogamia , included all plants with concealed reproductive parts, mosses , liverworts , ferns , algae and fungi . Botany was originally a hobby for upper-class women. These women would collect and paint flowers and plants from around the world with scientific accuracy. The paintings were used to record many species that could not be transported or maintained in other environments. Marianne North illustrated over 900 species in extreme detail with watercolor and oil paintings. Her work and many other women's botany work

6370-447: The other hand with medicine and pharmacology, giving rise to fields such as agronomy , horticultural botany, phytopathology and phytopharmacology . The study of plants is vital because they underpin almost all animal life on Earth by generating a large proportion of the oxygen and food that provide humans and other organisms with aerobic respiration with the chemical energy they need to exist. Plants, algae and cyanobacteria are

6461-404: The outcome of prehistoric selection over thousands of years from among wild ancestral plants with the most desirable characteristics. Botanists study how plants produce food and how to increase yields, for example through plant breeding , making their work important to humanity's ability to feed the world and provide food security for future generations. Botanists also study weeds, which are

6552-791: The pain killer aspirin is the acetyl ester of salicylic acid , originally isolated from the bark of willow trees, and a wide range of opiate painkillers like heroin are obtained by chemical modification of morphine obtained from the opium poppy . Popular stimulants come from plants, such as caffeine from coffee, tea and chocolate, and nicotine from tobacco. Most alcoholic beverages come from fermentation of carbohydrate -rich plant products such as barley (beer), rice ( sake ) and grapes (wine). Native Americans have used various plants as ways of treating illness or disease for thousands of years. This knowledge Native Americans have on plants has been recorded by enthnobotanists and then in turn has been used by pharmaceutical companies as

6643-490: The plants with a highly fermentable sugar or oil content that are used as sources of biofuels , important alternatives to fossil fuels , such as biodiesel . Sweetgrass was used by Native Americans to ward off bugs like mosquitoes . These bug repelling properties of sweetgrass were later found by the American Chemical Society in the molecules phytol and coumarin . Plant ecology is the science of

6734-486: The pollen either fails to reach the stigma or fails to germinate and produce male gametes . This is one of several methods used by plants to promote outcrossing . In many land plants the male and female gametes are produced by separate individuals. These species are said to be dioecious when referring to vascular plant sporophytes and dioicous when referring to bryophyte gametophytes . Charles Darwin in his 1878 book The Effects of Cross and Self-Fertilization in

6825-442: The polymer cutin which is found in the plant cuticle that protects land plants from drying out. Plants synthesise a number of unique polymers like the polysaccharide molecules cellulose , pectin and xyloglucan from which the land plant cell wall is constructed. Vascular land plants make lignin , a polymer used to strengthen the secondary cell walls of xylem tracheids and vessels to keep them from collapsing when

6916-556: The practical value of earlier "physic gardens", often associated with monasteries, in which plants were cultivated for suspected medicinal uses. They supported the growth of botany as an academic subject. Lectures were given about the plants grown in the gardens. Botanical gardens came much later to northern Europe; the first in England was the University of Oxford Botanic Garden in 1621. German physician Leonhart Fuchs (1501–1566)

7007-461: The rise of the related molecular-scale biological approaches of molecular biology , genomics , proteomics and metabolomics , the relationship between the plant genome and most aspects of the biochemistry, physiology, morphology and behaviour of plants can be subjected to detailed experimental analysis. The concept originally stated by Gottlieb Haberlandt in 1902 that all plant cells are totipotent and can be grown in vitro ultimately enabled

7098-680: The same fundamental principles of genetics as in other multicellular organisms. Gregor Mendel discovered the genetic laws of inheritance by studying inherited traits such as shape in Pisum sativum ( peas ). What Mendel learned from studying plants has had far-reaching benefits outside of botany. Similarly, " jumping genes " were discovered by Barbara McClintock while she was studying maize. Nevertheless, there are some distinctive genetic differences between plants and other organisms. Species boundaries in plants may be weaker than in animals, and cross species hybrids are often possible. A familiar example

7189-594: The sphere of interest of the International Botanical Congress . Nowadays, botanists (in the strict sense) study approximately 410,000 species of land plants , including some 391,000 species of vascular plants (of which approximately 369,000 are flowering plants ) and approximately 20,000 bryophytes . Botany originated in prehistory as herbalism with the efforts of early humans to identify – and later cultivate – plants that were edible, poisonous, and possibly medicinal, making it one of

7280-568: The spring gentian, are adapted to the alkaline conditions found on calcium -rich chalk and limestone , which give rise to often dry topographies such as limestone pavement . As for their growth habit , the flowering plants range from small, soft herbaceous plants , often living as annuals or biennials that set seed and die after one growing season, to large perennial woody trees that may live for many centuries and grow to many metres in height. Some species grow tall without being self-supporting like trees by climbing on other plants in

7371-427: The structure and function of enzymes and other proteins . In the last two decades of the 20th century, botanists exploited the techniques of molecular genetic analysis , including genomics and proteomics and DNA sequences to classify plants more accurately. Modern botany is a broad, multidisciplinary subject with contributions and insights from most other areas of science and technology. Research topics include

7462-688: The study of plant structure , growth and differentiation, reproduction , biochemistry and primary metabolism , chemical products, development , diseases , evolutionary relationships , systematics , and plant taxonomy . Dominant themes in 21st-century plant science are molecular genetics and epigenetics , which study the mechanisms and control of gene expression during differentiation of plant cells and tissues . Botanical research has diverse applications in providing staple foods , materials such as timber , oil , rubber, fibre and drugs, in modern horticulture , agriculture and forestry , plant propagation , breeding and genetic modification , in

7553-471: The study of plants. In 1665, using an early microscope, Polymath Robert Hooke discovered cells (a term he coined) in cork , and a short time later in living plant tissue. During the 18th century, systems of plant identification were developed comparable to dichotomous keys , where unidentified plants are placed into taxonomic groups (e.g. family, genus and species) by making a series of choices between pairs of characters . The choice and sequence of

7644-696: The synthesis of chemicals and raw materials for construction and energy production, in environmental management , and the maintenance of biodiversity . Botany originated as herbalism , the study and use of plants for their possible medicinal properties . The early recorded history of botany includes many ancient writings and plant classifications. Examples of early botanical works have been found in ancient texts from India dating back to before 1100 BCE, Ancient Egypt , in archaic Avestan writings, and in works from China purportedly from before 221 BCE. Modern botany traces its roots back to Ancient Greece specifically to Theophrastus ( c.  371 –287 BCE),

7735-526: The use of genetic engineering experimentally to knock out a gene or genes responsible for a specific trait, or to add genes such as GFP that report when a gene of interest is being expressed. These technologies enable the biotechnological use of whole plants or plant cell cultures grown in bioreactors to synthesise pesticides , antibiotics or other pharmaceuticals , as well as the practical application of genetically modified crops designed for traits such as improved yield. Modern morphology recognises

7826-485: The word plant (e.g. plant taxonomy, plant ecology, plant anatomy, plant morphology, plant systematics, plant ecology), or prefixing or substituting the prefix phyto- (e.g. phytochemistry , phytogeography ). The study of fossil plants is palaeobotany . Other fields are denoted by adding or substituting the word botany (e.g. systematic botany ). Phytosociology is a subfield of plant ecology that classifies and studies communities of plants. The intersection of fields from

7917-559: The world's staple calorie intake, and all three plants are cereals from the Poaceae family (colloquially known as grasses). Other families provide important industrial plant products such as wood , paper and cotton , and supply numerous ingredients for beverages , sugar production , traditional medicine and modern pharmaceuticals . Flowering plants are also commonly grown for decorative purposes , with certain flowers playing significant cultural roles in many societies. Out of

8008-483: Was coined in the form "Angiospermae" by Paul Hermann in 1690, including only flowering plants whose seeds were enclosed in capsules. The term angiosperm fundamentally changed in meaning in 1827 with Robert Brown , when angiosperm came to mean a seed plant with enclosed ovules. In 1851, with Wilhelm Hofmeister 's work on embryo-sacs, Angiosperm came to have its modern meaning of all the flowering plants including Dicotyledons and Monocotyledons. The APG system treats

8099-457: Was established in 1956, and was incorporated into the national park when it was created in 2005. The Ndumbi forest is also home to a 100-meter waterfall. Botanist Botany , also called plant science (or plant sciences ), plant biology or phytology , is the science of plant life and a branch of biology . A botanist , plant scientist or phytologist is a scientist who specialises in this field. The term "botany" comes from

8190-399: Was one of "the three German fathers of botany", along with theologian Otto Brunfels (1489–1534) and physician Hieronymus Bock (1498–1554) (also called Hieronymus Tragus). Fuchs and Brunfels broke away from the tradition of copying earlier works to make original observations of their own. Bock created his own system of plant classification. Physician Valerius Cordus (1515–1544) authored

8281-412: Was the beginning of popularizing botany to a wider audience. Increasing knowledge of plant anatomy , morphology and life cycles led to the realisation that there were more natural affinities between plants than the artificial sexual system of Linnaeus. Adanson (1763), de Jussieu (1789), and Candolle (1819) all proposed various alternative natural systems of classification that grouped plants using

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