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Download Gymnosperms Gymnosperms are non-flowering plants that do not
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Gymnosperms Gymnosperms are non-flowering plants that do not have a protective cover to their seeds. Read on to find out more... There are so many plants and trees that surround us. The refreshingly green trees in my garden and the august trees that stand tall at the side of the road are a source of great pleasure and a delight to watch. Plants and trees not only provide us with food, fuels and many other important things but are also a source of fresh air and joy that surrounds us everyday. There exist so many different types of plants and trees, which have minute differences amongst their color, structure, as well as numerous physiological differences. Often we miss these differences and similarities in plants since many of these differences are indiscernible to the human eye. There exists a special branch of science that involves study of plants in detail. Botany is the branch of science that deals with the study and classification of plants. According to the principles of Botany, higher plants are divided into two main groups known as angiosperms and gymnosperms. Angiosperms are flowering whereas the gymnosperms are nonflowering plants. Peculiar Characteristics of Gymnosperms Besides the basic differences mentioned above, there exist a set of standard feature or characteristics that help to identify gymnosperms. Here are some of the peculiar characteristics of gymnosperms: Gymnosperms do not have and outer-covering or shell around their seeds. Gymnosperms do not produce flowers barring a few exceptions. Gymnosperms are heterosporous which means that they produce different male and female spores. The microspores develop into pollen grains and the megaspores are in an ovule. Gymnosperms produce cones. Gymnosperms do not bear fruits. Gymnosperms propagate via wind pollination The word ‘gymnosperms’ originates from the words gymnos meaning naked and sperm meaning seed, the name is so because of the fact that seeds of gymnosperms are not surrounded by a protective wall which exists in the angiosperms. Gymnosperms are further separated into four divisions, which are as follows: Coniferophyta This is the largest division of gymnosperms, which includes Pines, Yews, Spruces, Junipers, Cedars and many more plants. These conifers are found in the high latitudes of the northern hemisphere. There are several families of the Coniferphyta division as well. These are cone-bearing gymnosperms, which date back to the carboniferous period. Cycadophyta This division includes palm-like gymnosperms, not to mention the surviving order Cycadales< and other extinct orders. The cycads are slow growing palm-like plants. These plants also have another characteristic feature that the leaves of these plants are borne together on the top of the trunk. The seeds of these plants are present on the surface of the scales of cones. Gingkophyta This group of the gymnosperms is relatively limited since it contains only one member. The single living species of the Gingkophyta division is the Gingko biloba from China. Gnetophyta These are gymnosperms, which are truly unique due to the fact that they bear flowers- a property that is exclusively attributed to the angiosperms. In addition to this, the xylem of these plants contains pollen-producing structures, which resemble the stamens in angiosperms. Owing to this, these plants are considered as a link between gymnosperms and angiosperms. The plants included in this division are tropical lianas, joint-firs and also several other plants. Different Kinds of Plants Plants evoke images of lush, green vegetation. The number of plant species is staggering. Read on to know about some kinds of plants. There are many different kinds of plants. These can be found in almost every type of habitat and come in a variety of sizes and shapes. Plants are an important source of nutrition for mankind and many of the herbs can be used as medicine. A few examples of different plant types are given below. Angiosperms Angiosperms belong to the family of vascular plants. They represent the most advanced condition among terrestrial plants. They have the ability to flower. They have tubes, which carry nutrients and water throughout the body of the plant. This kind of transportation is called the vascular system. The main function of the flower is to protect the plants seeds. Flowers form a part of the reproductive elements of angiosperms. The stamen produces the pollen, which is used to fertilize the egg in the carpel to produce more seeds. Angiosperms can have one of two types of seeds, dicots or monocots. Dicots possess flowers with four or five petals and complex leaves with veins. Dicots include sunflowers, catiapple trees, cherry trees and roses. Monocots have a single package of food. Their leaves are made of long strands, and petals in groups of three. Monocots include corn, lilies grass and palm trees. Monocots that are grown in large quantities to feed people and animals are pumpkins, potatoes, tomatoes, and peppers. The grass family of monocots includes wheat, barley, rye, sorghum, oats, millet and sugar. Annual, Perennial and Biennial plants Annual plants have a one-year life cycle while biennial plants have a two-year life cycle. Annual plants are divided into two categories – winter annuals and summer annuals. A plant can behave as an annual or a perennial according to local climatic and geographic growing conditions. Annual plants that naturally complete their life cycle in less than a year are called true annuals. Examples of true annuals are watermelon, pea and lettuce. Examples of biennials are parsley, carrot and celery. Perennial plant’s life cycle is more than two years. Sweet potato and tomato are examples of perennials. Epiphytic Plants They depend on other plants for support growing on trunks and branches. They are also dubbed ‘air plants’. Mosses and orchids are instances of epiphytic plants. Though they are not parasitic, they can be deleterious to their hosts. They have an advantage over plants growing on the ground as they have a relatively better access to sunlight. They obtain nutrients from the air or water around them. They use photosynthesis for the process of nutrition. Pitcher Plants They are carnivorous plants. Pitcher plant is also called a meat eater. They normally grow in marshlands, bogs and areas of waterlogged, acidic and nitrogen poor soil. They get their nitrogen intake by eating insects. They usually bear a single, large and nodding flower. The insect traps of a pitcher plant can be quite large and attractive. The inside of the tubular shaped leaf is lined with downward pointing hairs, which block an insect from climbing up the tube and escaping. The fluid in the bottom of the tube contains digestive juices that will ingest the insect prey. They will also consume small frogs and occasionally mice and small birds. They can also absorb nutrients through their root systems. Desert Plants These plants are adapted to the arid and hostile environment of a desert. These plants have the capability to store water. They also have the ability to use water efficiently. They usually have few or no leaves, which greatly reduces transpiration. Desert perennial species survive by being dormant during dry periods of the year. They spring to life when water becomes available. Plant species like cacti and succulents, have dense flesh which is capable of storing large amounts of water. Several plants have developed the typical spikes and spines to prevent them from being eaten by animals.