Saturday, June 9, 2012

Kingdom Protista

      Protists are a diverse group of eukaryotic microorganisms. Historically, protists were treated as the kingdom Protista, which includes mostly unicellular organisms that do not fit into the other kingdoms, but this group is contested in modern taxonomy. Instead, it is "better regarded as a loose grouping of 30 or 40 disparate phyla with diverse combinations of trophic modes, mechanisms of motility, cell coverings and life cycles."
       The protists do not have much in common besides a relatively simple organization either they are unicellular, or they are multicellular without specialized tissues. This simple cellular organization distinguishes the protists from other eukaryotes, such as fungi, animals and plants.Some members of Kingdom Protista are unicellular, others are colonial, and yet others are multicellular. Note that in the colonial forms, all the cells are similar with similar, generalized functions, whereas in the truly multicellular species, the “body” of the organism consists of a variety of types of cells, each type with its own specialized function. These organisms are all eukaryotes (they have a true nucleus). They all need some kind of a water-based environment--which can be fresh or marine water, snow, damp soil, polar bear hairs--in which to live. All are aerobic and have mitochondria to do cellular respiration, and some have chloroplasts and can do photosynthesis. Most of them reproduce or grow by mitosis, and some reproduce by meiosis and fertilization. Many can form cysts in adverse conditions. Protists are a major component of plankton.
  • Paramecium
  • Amoeba 
  • Giardia
  • Trichonympha

Friday, June 8, 2012

Kingdom Monera

             Monera is a kingdom that contains unicellular organisms without a nucleus (i.e., a prokaryotic cell organization), such as bacteria. The kingdom is considered superseded. The Kingdom Monera is the most numerous of all organisms, and makes up the only prokaryotic kingdom.  All of the Monerans share these characteristics:

  • All bacteria are prokaryotes.  (lack a membrane bound nucleus)
  • All bacteria are unicellular.  (only have one cell)
  • They may be spherical (coccus), rodlike (bacillus), spiral (spirillum).
  • On average, bacteria are 1 micrometre long and 0.5 micrometres wide.
  • Bacteria are surrounded by a lipid membrane.
  • A cell wall lies outside the cell membrane.
  • Bacteria move by flagella, secreting slime or by axial filiments.
  • Bacteria reproduce through binary fission, which is asexual.

  • Bacteria, 
  • Nostoc, 
  • Blue green algae, 
  • Bacillus, 
  • Halo bacterium ....  

Five kingdom classification

 Five kingdom classification

This is the five kingdom classification given by scientist Whittaker (1969).This scheme was based on -
  • Structure of Cells - {prokaryotic or eukaryotic }
  • Structure of Organism - {unicellular or Multicellular}
  • Mode of nutrition - Photosynthesis in green plants, absorption in fungi and ingestion in animals. 
  1.  Kingdom Monera
  2.  Kingdom Protista
  3.  Kingdom Fungi
  4.  Kingdom Plantae
  5.  Kingdom Animalia


              Biodiversity is the degree of variation of life forms within a given species, ecosystem, biome, or an entire planet. Biodiversity is a measure of the health of ecosystems. Biodiversity is in part a function of climate. In terrestrial habitats, tropical regions are typically rich whereas polar regions support fewer species.

           The sequel to that first biodiversity book, naturally titled Biodiversity II (Reaka-Kudla et al. 1997), documents the rapid rise of the term "biodiversity" in importance and influence. But it also traces the study of aspects of biodiversity back as far as Aristotle. To some extent, biodiversity merely offers a new, emotive, term for some older ideas and programs. In fact, "biodiversity" is now used sometimes to mean "life" or "wilderness" or other conservation values. "Biodiversity" also has served on occasion as a catch-all for "conservation" itself.
           The scientific literature illustrates how most any conservation activity might use the label "biodiversity". On the one hand, workers taking advantage of the acknowledged importance of the term have expanded its meaning to capture concerns at a fine scale, such as that focussing on a favourite single species. This focus might be referred to more accurately as one of "biospecifics". At the coarser scale, one important interpretation, discussed below, advocates a primary linkage of biodiversity to the maintenance of ecosystem processes — what might be called the "bio-processes" approach.
          The number of the problem of defining biodiversity is that it is hard to exclude anything from a concept that is taken so easily to mean "everything". Sarkar has argued that interpreting biodiversity across all biological levels, from genes to ecosystems, amounts to considering all biological entities, so that biodiversity absurdly "becomes all of biology".

         The term "biodiversity" is used in this context largely as an assumed foundation for ecosystem processes. Norton (2001) sees the process focus as replacing, not complementing, the "increasingly obsolete" inventory/items perspective of biodiversity, arguing that we "will likely move away from the inventory-of-objects approach altogether". The processes perspective is to determine how we look at biodiversity: "…applied to biodiversity policy, we can focus on the processes that have created and sustained the species and elements that currently exist, rather than on the species and elements themselves". Further, "it is reasonable to interpret advocates of biodiversity protection as valuing natural processes for their capacity to maintain support and repair damage to their parts".

    Taiga Biome:boreal forests

          Taiga Biome:boreal forests
                  Taiga is the world's largest land biome, and makes up 29% of the world's forest cover. the largest areas are located in Russia and Canada. The taiga is the terrestrial biome with the lowest annual average temperatures after the tundra and permanent ice caps. Extreme winter minimums in the northern taiga are typically lower than those of the tundra. The lowest reliably recorded temperatures in the Northern Hemisphere were recorded in the taiga of northeastern Russia. 
                   The growing season, when the vegetation in the taiga comes alive, is usually slightly longer than the climatic definition of summer as the plants of the boreal biome have a lower threshold to trigger growth. In Canada, Scandinavia and Finland, the growing season is often estimated by using the period of the year when the 24-hr average temperature is 5 °C or more. For the Taiga Plains in Canada, growing season varies from 80 to 150 days, and in the Taiga Shield from 100 to 140 days. Some sources claim 130 days growing season as typical for the taiga.Other sources mention that 50–100 frost-free days are characteristic. Data for locations in southwest Yukon gives 80–120 frost-free days. The closed canopy boreal forest in Kenozyorsky National Park near Plesetsk, Arkhangelsk Province, Russia, on average has 108 frost-free days.The longest growing season is found in the smaller areas with oceanic influences; in coastal areas of Scandinavia and Finland, the growing season of the closed boreal forest can be 145–180 days.
                Animals found in taiga include woodpeckers, hawks, moose, bear, weasel, lynx, fox, wolf, deer, hares, chipmunks, shrews, and bats. Mammals living in the boreal forests have all adapted in various ways to survive the long cold winters. Generally they have heavy fur coats and many hibernate through the winter.
    Growthform Adaptations: The main reasons firs, sprucs and pines are the dominant trees in the boreal forest, and thus define the biome is because they are adapted to the extreme conditions brough about by the cold, including the winter-induced drought and the short growing season. The following are some of the main adaptations we found that trees in this zone have:

    • Conical shape - promotes shedding of snow and prevents loss of branches.
    • Needleleafs - narrow leaves reduce surface area through which water can be lost (transpired), especially in the winter when the frozen ground prevents plants from replenishing their water supply. The needles of boreal conifers also have thick waxy coatings--a waterproof cuticle--in which stomata are sunken and protected from drying winds.
    • Evergreen habit - retention of foliage allows plants to photosynthesize as soon as temperatures permit in spring, rather than having to waste time in the short growing season merely growing leaves. [Note: Deciduous larch are dominant in areas underlain by nearly continuous permafrost and having a climate even too dry and cold for the waxy needles of spruce and fir.]
    • Dark color - the dark green of spruce and fir needles helps the foliage absorb maximum heat from the sun and begin photosynthesis as early as possible.

    Thursday, June 7, 2012

    Coniferous forest biome

    Coniferous forest biome
                    Coniferous forest ecosystems are found in regions of the Earth that experience somewhat long and cold winters, with summer being much shorter. Thus, it is no surprise that these biomes are more common the closer one travels towards the Earth’s poles. Additionally, this biome is found high atop mountains where temperatures tend to be lower and winter tends to last longer.
    The Coniferous Forest is a forest of Conifers. A Conifer is a tree that produces its seeds in cones.  The Pine tree is the most common example.  Conifer leaves conserve water with the thick, waxy layer that covers their leaves, also known as needles.  The vegitation in the Coniferous forest is small in size, but large enough to feed the vast herbivore population.  Most of these animals survive the brutal winters by migrating or hibernating. 
    Average Annual Rainfall- 14-29.5 in.
    Average Temperatures in the Summer- 57.2°F
    Average Temperatures in the Winter- 14°F
    Temperate coniferous forest         

    Temperate coniferous forest is a terrestrial biome found in temperate regions of the world with warm summers and cool winters and adequate rainfall to sustain a forest. In most temperate coniferous forests, evergreen conifers predominate, while some are a mix of conifers and broad leaf evergreen trees and/or broad leaf deciduous trees. . Coniferous forests can be found in the United States, Canada, Europe, and Asia. Many species of trees inhabit these forests including cedar, cypress, douglas-fir,pine, podocarpus, spruce, redwood and yew. The understory also contains a wide variety of herbaceous and shrub species.

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