Saturday, 10 December 2011

Solar System

Solar System


           The Solar System consists of the Sun and the astronomical objects gravitationally bound in orbit around it, all of which formed from the collapse of a giant molecular cloud approximately 4.6 billion years ago. The vast majority of the system's mass (well over 99%) is in the Sun.  The four smaller inner planets, MercuryVenusEarth and Mars, also called the terrestrial planets, are primarily composed of rock and metal. The four outer planets, the gas giants, are substantially more massive than the terrestrials. The two largest, Jupiter and Saturn, are composed mainly of hydrogen and helium; the two outermost planets, Uranus and Neptune, are composed largely of ices, such as water, ammonia and methane, and are often referred to separately as "ice giants". The asteroid belt, which lies between Mars and Jupiter, is similar to the terrestrial planets as it is composed mainly of rock and metal. Beyond Neptune's orbit lie the Kuiper belt and scattered disc; linked populations of trans-Neptunian objects composed mostly of ices such as water, ammonia and methane. Within these populations, five individual objects, CeresPlutoHaumeaMakemake and Eris, are recognized to be large enough to have been rounded by their own gravity, and are thus termed dwarf planets. In addition to thousands of small bodies in those two regions, various other small body populations, such as cometscentaurs and interplanetary dust, freely travel between regions. Six of the planets and three of the dwarf planets are orbited by natural satellites, usually termed "moons" after Earth's Moon. Each of the outer planets is encircled by planetary rings of dust and other particles. The solar wind, a flow of plasma from the Sun, creates a bubble in the interstellar medium known as the heliosphere, which extends out to the edge of the scattered disc. The hypothetical Oort cloud, which acts as the source for long-period comets, may also exist at a distance roughly a thousand times further than the heliosphere.












       The  Solar  System  Song 







Wednesday, 7 December 2011

Reproduction of Plants

Plants have two main types of asexual reproduction in which new plants are produced that are genetically identical clones of the parent individual. Vegetative reproduction involves a vegetative piece of the original plant and is distinguished from apomixis", which is a "replacement" for sexual reproduction.
Natural vegetative reproduction is mostly a process found in herbaceous and woody perennial plants, and typically involves structural modifications of the stem or roots and in a few species leaves. Most plant species that employ vegetative reproduction do so as a means to perennialize the plants, allowing them to survive from one season to the next and often facilitating their expansion in size. A plant that persists in a location through vegetative reproduction of individuals constitutes a clonal colony, a single ramet, or apparent individual, of a clonal colony is genetically identical to all others in the same colony. The distance that a plant can move during vegetative reproduction is limited, though some plants can produce ramets from branching rhizomes or stolons that cover a wide area, often in only a few growing seasons. In a sense, this process is not one of "reproduction" but one of survival and expansion of biomass of the individual. When an individual organism increases in size via cell multiplication and remains intact, the process is called "vegetative growth". However, in vegetative reproduction, the new plants that result are new individuals in almost every respect except genetic. A major disadvantage to vegetative reproduction, is the transmission of pathogens from parent to daughter plants; it is uncommon for pathogens to be transmitted from the plant to its seeds, though there are occasions when it occurs. A number of asexual methods are utilized which are usually enhancements of natural processes, including: cutting, grafting, budding, layering, division, sectioning of rhizomes or roots, stolons, tillers (suckers) and artificial propagation by laboratory tissue cloning. Asexual methods are most often used to propagate cultivars with individual desirable characteristics that do not come true from seed. Fruit tree propagation is frequently performed by budding or grafting desirable cultivars (clones), onto rootstocks that are also clones, propagated by layering.  Since vegetatively propagated plants are clones, they are important tools in plant research. When a clone is grown in various conditions, differences in growth can be ascribes to environmental effects instead of genetic differences.

Below are the various ways plants reproduce :


Seeds 





Stem Cuttting




Sucker





Underground Stem







The Life  Cycle Of  A  Flower
    
       

Photosynthesis

Photosynthesis


Photosynthesis is a chemical process that converts carbon dioxide into organic compounds, especially sugars, using the energy from sunlight. Photosynthesis occurs in plantsalgae, and many species of bacteria. Photosynthetic organisms are called photoautotrophs, since they can create their own food. In plants, algae, and cyanobacteria, photosynthesis uses carbon dioxide and water, releasing oxygen as a waste product. Photosynthesis is vital for all aerobic life on Earth. In addition to maintaining normal levels of oxygen in the atmosphere, photosynthesis is the source of energy for nearly all life on earth, either directly, through primary production, or indirectly, as the ultimate source of the energy in their food, the exceptions being chemoautotrophs that live in rocks or around deep sea hydrothermal vents. The rate of energy capture by photosynthesis is immense, approximately 100 terawatts, which is about six times larger than the power consumption of human civilization. As well as energy, photosynthesis is also the source of the carbon in all the organic compounds within organisms' bodies. In all, photosynthetic organisms convert around 100–115  petagrams of carbon into biomass per year.
Although photosynthesis can happen in different ways in different species, some features are always the same. For example, the process always begins when energy from light is absorbed by proteins called photosynthetic reaction centers that contain chlorophylls. In plants, these proteins are held inside organelles called chloroplasts, while in bacteria they are embedded in the plasma membrane. Some of the light energy gathered by chlorophylls is stored in the form of adenosine triphosphate (ATP). The rest of the energy is used to remove electrons from a substance such as water. These electrons are then used in the reactions that turn carbon dioxide into organic compounds. In plants, algae and cyanobacteria, this is done by a sequence of reactions called the Calvin cycle, but different sets of reactions are found in some bacteria, such as the reverse Krebs cycle in Chlorobium. Many photosynthetic organisms haveadaptations that concentrate or store carbon dioxide. This helps reduce a wasteful process called photorespiration that can consume part of the sugar produced during photosynthesis.








            Photosynthesis  Song



Saturday, 3 December 2011

Type of plants


Vegetable Plants
Vegetable plants can be consumed raw, some may be eaten cooked, and some must be cooked in order to be edible. Vegetable plants are most often cooked with salty dishes. However, a few vegetables are often used in desserts and other sweet dishes, such as rhubarb pie and carrot cake.



Edible Plants
 Edible plants includes plants with parts that are safely edible by humans. The edible parts were obtained equally from wild plants and cultivated plants. A total of 28 species were eaten cooked compared to 23 species eaten raw. It is important not only to record such native knowledge and conduct further studies but also to take steps to conserve the genetic diversity of edible plants before they are lost to human kind forever.



Herb Plants

Herb plants are plants with leaves, seeds, or flowers used for flavouring, food, medicine, perfume or a part of a plant used in cooking. Herbs have a variety of uses including culinary, medicinal, and in some cases spiritual usage. General usage differs between culinary herbs and medicinal herbs. Herb plants include the part of leaves, roots, flowers, seeds, resin, root bark, inner bark, berries and sometimes the pericarp or other portions of the plant. 




Nut and Seed Plants

Nuts are an important source of nutrients for both humans and wildlife. Nuts are a composite of the seed and the fruit, where the fruit does not open to release the seed. Most seeds come from fruits, and the seeds are free of the fruit, unlike nuts such as hazelnuts, hickories, chestnuts and acorns, which have a stony fruit wall and originate from a compound ovary. Culinary usage of the term is less restrictive, and some nuts as defined in food preparation. 




Spice Plants

 A Spice Plant is a kind of tree that returns Allspice when harvested. The higher Gardening skill the player has, the more Allspice will be obtained. They can be found in Shimla, Mirch, Chakra Phool and Jethimadh. Spice Plants can also be planted in a patch in your house's backyard with a Spice Plant Bean.









Aquatic Plant

Aquatic plants are plants that have adapted to living in aquatic environments (saltwater or freshwater). These plants require special adaptations for living submerged in water, or at the water's surface. Aquatic plants can only grow in water or in soil that is permanently saturated with water. Aquatic vascular plants can be ferns or angiosperms.





Toxic Plants

Most poisonous plants have an unpleasant taste that animals avoid if they have anything 
else to eat.  However, if they have no choice but to eat these plants, they might develop a 
taste for them. 




Flowers

A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants . The biological function of a flower is to effect reproduction, usually by providing a mechanism for the union of sperm with eggs.  Some flowers produce spores without fertilization. Flowers contain sporangia and are the site where gametophytes develop. Flowers give rise to fruit and seeds. Many flowers have evolved to be attractive to animals, so as to cause them to be vectors for the transfer of pollen. In addition to facilitating the reproduction of flowering plants, flowers have long been admired and used by humans to beautify their environment, but also as objects of romance, ritual, religion, medicine and as a source of food.