The flowering plants known as angiosperms, Angiospermae or Magnoliophyta, are the most diverse group of land plants, with 64 orders, 416 families 13,164 known genera and c. 369,000 known species. Like gymnosperms, angiosperms are seed-producing plants. However, they are distinguished from gymnosperms by characteristics including flowers, endosperm within the seeds, the production of fruits that contain the seeds. Etymologically, angiosperm means a plant; the term comes from the Greek words sperma. The ancestors of flowering plants diverged from gymnosperms in the Triassic Period, 245 to 202 million years ago, the first flowering plants are known from 160 mya, they diversified extensively during the Early Cretaceous, became widespread by 120 mya, replaced conifers as the dominant trees from 100 to 60 mya. Angiosperms differ from other seed plants in several ways, described in the table below; these distinguishing characteristics taken together have made the angiosperms the most diverse and numerous land plants and the most commercially important group to humans.
Angiosperm stems are made up of seven layers. The amount and complexity of tissue-formation in flowering plants exceeds that of gymnosperms; the vascular bundles of the stem are arranged such that the phloem form concentric rings. In the dicotyledons, the bundles in the young stem are arranged in an open ring, separating a central pith from an outer cortex. In each bundle, separating the xylem and phloem, is a layer of meristem or active formative tissue known as cambium. By the formation of a layer of cambium between the bundles, a complete ring is formed, a regular periodical increase in thickness results from the development of xylem on the inside and phloem on the outside; the soft phloem becomes crushed, but the hard wood persists and forms the bulk of the stem and branches of the woody perennial. Owing to differences in the character of the elements produced at the beginning and end of the season, the wood is marked out in transverse section into concentric rings, one for each season of growth, called annual rings.
Among the monocotyledons, the bundles are more numerous in the young stem and are scattered through the ground tissue. They once formed the stem increases in diameter only in exceptional cases; the characteristic feature of angiosperms is the flower. Flowers show remarkable variation in form and elaboration, provide the most trustworthy external characteristics for establishing relationships among angiosperm species; the function of the flower is to ensure fertilization of the ovule and development of fruit containing seeds. The floral apparatus may arise terminally from the axil of a leaf; as in violets, a flower arises singly in the axil of an ordinary foliage-leaf. More the flower-bearing portion of the plant is distinguished from the foliage-bearing or vegetative portion, forms a more or less elaborate branch-system called an inflorescence. There are two kinds of reproductive cells produced by flowers. Microspores, which will divide to become pollen grains, are the "male" cells and are borne in the stamens.
The "female" cells called megaspores, which will divide to become the egg cell, are contained in the ovule and enclosed in the carpel. The flower may consist only of these parts, as in willow, where each flower comprises only a few stamens or two carpels. Other structures are present and serve to protect the sporophylls and to form an envelope attractive to pollinators; the individual members of these surrounding structures are known as petals. The outer series is green and leaf-like, functions to protect the rest of the flower the bud; the inner series is, in general, white or brightly colored, is more delicate in structure. It functions to attract bird pollinators. Attraction is effected by color and nectar, which may be secreted in some part of the flower; the characteristics that attract pollinators account for the popularity of flowers and flowering plants among humans. While the majority of flowers are perfect or hermaphrodite, flowering plants have developed numerous morphological and physiological mechanisms to reduce or prevent self-fertilization.
Heteromorphic flowers have short carpels and long stamens, or vice versa, so animal pollinators cannot transfer pollen to the pistil. Homomorphic flowers may employ a biochemical mechanism called self-incompatibility to discriminate between self and non-self pollen grains. In other species, the male and female parts are morphologically separated, developing on different flowers; the botanical term "Angiosperm", from the Ancient Greek αγγείον, angeíon and σπέρμα, was coined in the form Angiospermae by Paul Hermann in 1690, as the name of one of his primary divisions of the plant kingdom. This included flowering plants possessing seeds enclosed in capsules, distinguished from his Gymnospermae, or flowering plants with achenial or schizo-carpic fruits, the whole fruit or each of its pieces being here regarded as a seed and naked; the term and its antonym were maintained by Carl Linnaeus with the same sense, but with restricted application, in the names of the orders of his class Didynamia. Its use with any
Plants are multicellular, predominantly photosynthetic eukaryotes of the kingdom Plantae. Plants were treated as one of two kingdoms including all living things that were not animals, all algae and fungi were treated as plants. However, all current definitions of Plantae exclude the fungi and some algae, as well as the prokaryotes. By one definition, plants form the clade Viridiplantae, a group that includes the flowering plants and other gymnosperms and their allies, liverworts and the green algae, but excludes the red and brown algae. Green plants obtain most of their energy from sunlight via photosynthesis by primary chloroplasts that are derived from endosymbiosis with cyanobacteria, their chloroplasts contain b, which gives them their green color. Some plants are parasitic or mycotrophic and have lost the ability to produce normal amounts of chlorophyll or to photosynthesize. Plants are characterized by sexual reproduction and alternation of generations, although asexual reproduction is common.
There are about 320 thousand species of plants, of which the great majority, some 260–290 thousand, are seed plants. Green plants provide a substantial proportion of the world's molecular oxygen and are the basis of most of Earth's ecosystems on land. Plants that produce grain and vegetables form humankind's basic foods, have been domesticated for millennia. Plants have many cultural and other uses, as ornaments, building materials, writing material and, in great variety, they have been the source of medicines and psychoactive drugs; the scientific study of plants is known as a branch of biology. All living things were traditionally placed into one of two groups and animals; this classification may date from Aristotle, who made the distincton between plants, which do not move, animals, which are mobile to catch their food. Much when Linnaeus created the basis of the modern system of scientific classification, these two groups became the kingdoms Vegetabilia and Animalia. Since it has become clear that the plant kingdom as defined included several unrelated groups, the fungi and several groups of algae were removed to new kingdoms.
However, these organisms are still considered plants in popular contexts. The term "plant" implies the possession of the following traits multicellularity, possession of cell walls containing cellulose and the ability to carry out photosynthesis with primary chloroplasts; when the name Plantae or plant is applied to a specific group of organisms or taxon, it refers to one of four concepts. From least to most inclusive, these four groupings are: Another way of looking at the relationships between the different groups that have been called "plants" is through a cladogram, which shows their evolutionary relationships; these are not yet settled, but one accepted relationship between the three groups described above is shown below. Those which have been called "plants" are in bold; the way in which the groups of green algae are combined and named varies between authors. Algae comprise several different groups of organisms which produce food by photosynthesis and thus have traditionally been included in the plant kingdom.
The seaweeds range from large multicellular algae to single-celled organisms and are classified into three groups, the green algae, red algae and brown algae. There is good evidence that the brown algae evolved independently from the others, from non-photosynthetic ancestors that formed endosymbiotic relationships with red algae rather than from cyanobacteria, they are no longer classified as plants as defined here; the Viridiplantae, the green plants – green algae and land plants – form a clade, a group consisting of all the descendants of a common ancestor. With a few exceptions, the green plants have the following features in common, they undergo closed mitosis without centrioles, have mitochondria with flat cristae. The chloroplasts of green plants are surrounded by two membranes, suggesting they originated directly from endosymbiotic cyanobacteria. Two additional groups, the Rhodophyta and Glaucophyta have primary chloroplasts that appear to be derived directly from endosymbiotic cyanobacteria, although they differ from Viridiplantae in the pigments which are used in photosynthesis and so are different in colour.
These groups differ from green plants in that the storage polysaccharide is floridean starch and is stored in the cytoplasm rather than in the plastids. They appear to have had a common origin with Viridiplantae and the three groups form the clade Archaeplastida, whose name implies that their chloroplasts were derived from a single ancient endosymbiotic event; this is the broadest modern definition of the term'plant'. In contrast, most other algae not only have different pigments but have chloroplasts with three or four surrounding membranes, they are not close relatives of the Archaeplastida having acquired chloroplasts separately from ingested or symbiotic green and red algae. They are thus not included in the broadest modern definition of the plant kingdom, although they were in the past; the green plants or Viridiplantae were traditionally divided into the green algae (including
Costa Rica the Republic of Costa Rica, is a country in Central America, bordered by Nicaragua to the north, the Caribbean Sea to the northeast, Panama to the southeast, the Pacific Ocean to the southwest, Ecuador to the south of Cocos Island. It has a population of around 5 million in a land area of 51,060 square kilometers. An estimated 333,980 people live in the capital and largest city, San José with around 2 million people in the surrounding metropolitan area; the sovereign state of Costa Rica is a unitary presidential constitutional republic. It is known for its long-standing and stable democracy, for its educated workforce, most of whom speak English; the country spends 6.9% of its budget on education, compared to a global average of 4.4%. Its economy, once dependent on agriculture, has diversified to include sectors such as finance, corporate services for foreign companies and ecotourism. Many foreign manufacturing and services companies operate in Costa Rica's Free Trade Zones where they benefit from investment and tax incentives.
Costa Rica was facing a market liquidity crisis in 2017 due to a growing budget deficit. By August 2017, the Treasury was having difficulty paying its obligations. Other challenges facing the country in its attempts to improve the economy by increasing foreign investment include a poor infrastructure and a need to improve public sector efficiency. Costa Rica was sparsely inhabited by indigenous peoples before coming under Spanish rule in the 16th century, it remained a peripheral colony of the empire until independence as part of the First Mexican Empire, followed by membership in the United Provinces of Central America, from which it formally declared independence in 1847. Since Costa Rica has remained among the most stable and progressive nations in Latin America. Following the brief Costa Rican Civil War, it permanently abolished its army in 1949, becoming one of only a few sovereign nations without a standing army; the country has performed favorably in the Human Development Index, placing 69th in the world as of 2015, among the highest of any Latin American nation.
It has been cited by the United Nations Development Programme as having attained much higher human development than other countries at the same income levels, with a better record on human development and inequality than the median of the region. Costa Rica has progressive environmental policies, it is the only country to meet all five UNDP criteria established to measure environmental sustainability. It was ranked 42nd in the world, third in the Americas, in the 2016 Environmental Performance Index, was twice ranked the best performing country in the New Economics Foundation's Happy Planet Index, which measures environmental sustainability, was identified by the NEF as the greenest country in the world in 2009. Costa Rica plans to become a carbon-neutral country by 2021. By 2016, 98.1% of its electricity was generated from green sources hydro, solar and biomass. Historians have classified the indigenous people of Costa Rica as belonging to the Intermediate Area, where the peripheries of the Mesoamerican and Andean native cultures overlapped.
More pre-Columbian Costa Rica has been described as part of the Isthmo-Colombian Area. Stone tools, the oldest evidence of human occupation in Costa Rica, are associated with the arrival of various groups of hunter-gatherers about 10,000 to 7,000 years BCE in the Turrialba Valley; the presence of Clovis culture type spearheads and arrows from South America opens the possibility that, in this area, two different cultures coexisted. Agriculture became evident in the populations, they grew tubers and roots. For the first and second millennia BCE there were settled farming communities; these were small and scattered, although the timing of the transition from hunting and gathering to agriculture as the main livelihood in the territory is still unknown. The earliest use of pottery appears around 2,000 to 3,000 BCE. Shards of pots, cylindrical vases, platters and other forms of vases decorated with grooves and some modelled after animals have been found; the impact of indigenous peoples on modern Costa Rican culture has been small compared to other nations, since the country lacked a strong native civilization to begin with.
Most of the native population was absorbed into the Spanish-speaking colonial society through inter-marriage, except for some small remnants, the most significant of which are the Bribri and Boruca tribes who still inhabit the mountains of the Cordillera de Talamanca, in the southeastern part of Costa Rica, near the frontier with Panama. The name la costa rica, meaning "rich coast" in the Spanish language, was in some accounts first applied by Christopher Columbus, who sailed to the eastern shores of Costa Rica during his final voyage in 1502, reported vast quantities of gold jewelry worn by natives; the name may have come from conquistador Gil González Dávila, who landed on the west coast in 1522, encountered natives, appropriated some of their gold. During most of the colonial period, Costa Rica was the southernmost province of the Captaincy General of Guatemala, nominally part of the Viceroyalty of New Spain. In practice, the captaincy general was a autonomous entity within the Spanish Empire.
Costa Rica's distance from the capital of the captaincy in Guatemala, its legal prohibition under Spanish law from trade with its southern neighbor Panama part of the Viceroyalty of New Granada, lack of r
Piperales is a botanical name for an order of flowering plants. It includes the family Piperaceae but otherwise has been treated variously over time. Well-known plants which may be included in this order include black pepper, lizard's tail and wild ginger. In the APG IV system, of 2016, this order is placed in the clade magnoliids and is circumscribed as follows: order Piperales family Aristolochiaceae family Piperaceae family SaururaceaeThis is an expansion from the APG system, of 1998, which used the same placement but used this circumscription: order Piperales family Aristolochiaceae family Lactoridaceae family Piperaceae family Saururaceae The Cronquist system, of 1981, placed the order in the subclass Magnoliidae of class Magnoliopsida and used this circumscription: order Piperales family Chloranthaceae family Piperaceae family SaururaceaeThe Engler system, in its update of 1964, placed the order in subclassis Archichlamydeae in class Dicotyledoneae and used this circumscription: order Piperales family Chloranthaceae family Lactoridaceae family Piperaceae family SaururaceaeThe Wettstein system, latest version published in 1935, assigned the order to the Monochlamydeae in subclass Choripetalae of class Dicotyledones.
It used the circumscription: order Piperales family Piperaceae
Peperomia camptotricha is a species of plant in the Piperaceae family endemic to Mexico. The Internet Peperomia Reference
Peperomia blanda, the arid-land peperomia, is a species of herb in the Piperaceae family. The species has a natural pan-tropical distribution that encompasses Asia, Australasia and the Americas; the species grows as a perennial, somewhat succulent herb to 30 cm in height, though the form varies from prostrate and creeping to up to 60 cm tall depending on environment and genotype. The typical habitat is damp rock crevices and steep stream banks. Https://books.google.com/books?id=cUNCAAAAIAAJ&pg=PA273&lpg=PA273&#v=onepage&q&f=false http://www.biodiversityexplorer.org/plants/piperaceae/peperomia.htm http://plantnet.rbgsyd.nsw.gov.au/cgi-bin/NSWfl.pl?page=nswfl&lvl=in&name=Peperomia~blanda~var.+floribunda
Peperomia pernambucensis is a species of plant in the Piperaceae family. Peperomia aphanoneura C. DC. Peperomia atirroana Trel. Peperomia balsapuertana Trel. Peperomia brevicaulis Trel. Peperomia breviscapa Trel. Peperomia lechleriana Trel. Peperomia longifolia C. DC. Peperomia lopezensis Trel. Peperomia paniculata Regel Peperomia subacaulis Trel; the Plant List entry JSTOR entry GBIF entry