Volcanic

When the molten rock come out to the surface of earth from the deep inside volcanic mountains are formed


  • Mount fuji in japan
  • Mount Kilimanjaro in Africa
  • Mount Vesuvius in italy
  • volcano is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lavavolcanic ash, and gases to escape from a magma chamber below the surface.

    Earth’s volcanoes occur because its crust is broken into 17 major, rigid tectonic plates that float on a hotter, softer layer in its mantle.[1]Therefore, on Earth, volcanoes are generally found where tectonic plates are diverging or converging, and most are found underwater. For example, a mid-oceanic ridge, such as the Mid-Atlantic Ridge, has volcanoes caused by divergent tectonic plates whereas the Pacific Ring of Fire has volcanoes caused by convergent tectonic plates. Volcanoes can also form where there is stretching and thinning of the crust’s plates, e.g., in the East African Rift and the Wells Gray-Clearwater volcanic field and Rio Grande Rift in North America. This type of volcanism falls under the umbrella of “plate hypothesis” volcanism.[2] Volcanism away from plate boundaries has also been explained as mantle plumes. These so-called “hotspots“, for example Hawaii, are postulated to arise from upwelling diapirs with magma from the core–mantle boundary, 3,000 km deep in the Earth. Volcanoes are usually not created where two tectonic plates slide past one another.

    Erupting volcanoes can pose many hazards, not only in the immediate vicinity of the eruption. One such hazard is that volcanic ash can be a threat to aircraft, in particular those with jet engines where ash particles can be melted by the high operating temperature; the melted particles then adhere to the turbineblades and alter their shape, disrupting the operation of the turbine. Large eruptions can affect temperature as ash and droplets of sulfuric acid obscure the sun and cool the Earth’s lower atmosphere (or troposphere); however, they also absorb heat radiated from the Earth, thereby warming the upper atmosphere (or stratosphere). Historically, volcanic winters have caused catastrophic famines.

 

Aeroplanes.

An airplane or aeroplane (informally plane) is a powered, fixed-wing aircraft that is propelled forward by from a jet engine, propeller or rocket engine. Airplanes come in a variety of sizes, shapes, and wing configurations. The broad spectrum of uses for airplanes includes recreation, transportation of goods and people, military, and research. Worldwide, commercial aviation transports more than four billion passengers annually on airliners[1] and transports more than 200 billion tonnekilometres[2] of cargo annually, which is less than 1% of the world’s cargo movement.[3] Most airplanes are flown by a pilot on board the aircraft, but some are designed to be remotely or computer-controlled.

The Wright brothers invented and flew the first airplane in 1903, recognized as “the first sustained and controlled heavier-than-air powered flight”.[4] They built on the works of George  Cayley dating from 1799, when he set forth the concept of the modern airplane (and later built and flew models and successful passenger-carrying gliders).[5] Between 1867 and 1896, the German pioneer of human aviation Otto Lilienthal also studied heavier-than-air flight. Following its limited use in World War I, aircraft technology continued to develop. Airplanes had a presence in all the major battles of World War II. The first jet aircraft was the German Heinkel He 178 in 1939. The first jet airliner, the de Havilland Comet, was introduced in 1952. The Boeing 707, the first widely successful commercial jet, was in commercial service for more than 50 years, from 1958 to at least 2013

 

FORESTS.

A forest is a large area dominated by trees.[1] Hundreds of more precise definitions of forest are used throughout the world, incorporating factors such as tree density, tree height, land use, legal standing and ecological function.[2][3][4] According to the widely used[5][6] Food and Agriculture Organization definition, forests covered 4 billion hectares (9.9×109 acres) (15 million square miles) or approximately 30 percent of the world’s land area in 2006.[4]

Forests are the dominant terrestrial ecosystem of Earth, and are distributed around the globe.[7] Forests account for 75% of the gross primary productivity of the Earth’s biosphere, and contain 80% of the Earth’s plant biomass. Net primary production is estimated at 21.9 carbon per year for tropical forests, 8.1 for temperate forests, and 2.6 for boreal forests.[7]

Forests at different latitudes and elevations form distinctly different ecozones: boreal forests near the poles, tropical forests near the equator and temperate forests at mid-latitudes. Higher elevation areas tend to support forests similar to those at higher latitudes, and amount of precipitation also affects forest composition.

Human society and forests influence each other in both positive and negative ways.[8] Forests provide ecosystem services to humans and serve as tourist attractions. Forests can also affect people’s health. Human activities, including harvesting forest resources, can negatively affect forest ecosystems.

 

 

SCIENCE.

 

Science (from Latin, meaning “knowledge”)[1][2]:58 is a systematic enterprise that builds and organizes knowledge in the form of testable explanations and predictions about the universe.[a]

The earliest roots of science can be traced to Ancient Egypt and Mesopotamia in around 3500 to 3000 BC.[3][4] Their contributions to mathematics, astronomy, and medicine entered and shaped Greek natural philosophy of classical antiquity, whereby formal attempts were made to explain events of the physical world based on natural causes.[3][4] After the fall of the Western Roman Empire, knowledge of Greek conceptions of the world deteriorated in Western Europe during the early centuries (400 to 1000 CE) of the Middle Ages[5] but was preserved in the Islamic Golden Age.[6] The recovery and assimilation of Greek works and Islamic inquiries into Western Europe from the 10th to 13th century revived natural philosophy,[5][7] which was later transformed by the Scientific Revolution that began in the 16th century[8] as new ideas and discoveries departed from previous Greek conceptions and traditions.[9][10][11][12] The scientific method soon played a greater role in knowledge creation and it was not until the 19th century that many of the institutional and professional features of science began to take shape.[13][14][15]

Stem

Plant Stem

A stem is one of two main structural axes of a vascular plant, the other being the root. The stem is normally divided into nodes and internodes:

The term “shoots” is often confused with “stems”; “shoots” generally refers to new fresh plant growth including both stems and other structures like leaves or flowers. In most plants stems are located above the soil surface but some plants have underground stems.

Stems have four main functions which are:

  • Support for and the elevation of leaves, flowers and fruits. The stems keep the leaves in the light and provide a place for the plant to keep its flowers and fruits.
  • Transport of fluids between the roots and the shoots in the xylem and phloem
  • Storage of nutrients
  • Production of new living tissue. The normal lifespan of plant cells is one to three years. Stems have cells called meristems that annually generate new living tissue.

Example.

 

THANK YOU.

Education

Education


Image result for importance of education


Education gives us a knowledge of the world around us and changes it into something better. It develops in us a perspective of looking at life. It helps us build opinions and have points of view on things in life. People debate over the subject of whether education  is the only thing that gives knowledge.


 

Where I study .

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ORCHIDS THE INTERNATIONAL SCHOOL

ORCHIDS HAS THE BEST EDUCATION 360 LEARNIG CURRICULM .  THIS SCHOOL IS MY FAVOURITE AS ALL THE TEACHERS ARE REALLY KIND,READY TO DO ANY THING FOR US TO LEARN  THE SYLABUS AND MAKE US THOROUGH FOR ARE INTERESTING OLYMPIADS,EXAMS AND MIND BLOWING ACTIVITIES. ALL I CAN SAY ABOUT THIS SCHOOL THAT IT’S THE BEST SCHOOL ASSOSIATION IN INDIA  !

  • Plant stem, the aboveground structures that have vascular tissue and that support leaves and flowers
  • Stem cell, an undifferentiated biological cell that can differentiate into specialized cells
  • Stem group, of a clade (in biological classification), consists of extinct organisms more closely related to the crown group than to any other extant clade