Biology Homeostasis Is of Vital Essay

3)

A seed is really a small plant embryo, surrounded by a nutritional layer known as the endosperm, all of which is covered in a hard protective shell called the seed coating. Fertilization occurred; all that is needed is the proper environment to encourage the embryo to grow. When this occurs, the plant quickly sprouts, first producing stem and leaves for support and the gathering of water and nutrients, as well as the production of energy via photosynthesis.

Roots also grow, absorbing nutrients and moisture from the soil. Transfer of nutrients from the roots to the higher portions of the plant, as well as some transfer of energy from the photosynthesis occurring above the ground to the roots, is facilitated by certain cells within the stem of the plant. The production of flower petals and the plant's reproductive organs occurs last in the plant's life cycle; for some plants this step occurs only once, for others it happens more often. For flowering plants of both types, however, the basic parts and the means of reproduction that they facilitate are virtually identical, though they are also quite complex.

Pollen grows on the anther, which itself grows at the end of a filament. This is the male reproductive organ of the plant, known collectively as the stamen. In order for a plant to reproduce (either with itself or with another plant), pollen (which contains two sperm cells per pollen grain) must be transferred to the carpel. When this occurs, tubules grow down into the ovary, allowing the sperm cells from the pollen to travel down and fertilize the ovum of the plant, which will mature into embryos and then seeds, which will themselves be released to start the process over.

4)

Easter Island, according to the available evidence, was a pristine wilderness before human beings first arrived on the small and remote island.After their arrival, things appeared to have gone downhill very quickly, with the destruction of the forests on the island and the rapid replacement of tress with grasses. After several centuries, some of the natural resources that the human population had grown entirely dependent on for supporting their way of life on Easter Island -- especially the palm tress -- were no longer plentiful enough to provide for the humans' needs.

In his article detailing this progression, Jared Diamond notes that "Easter Island is Earth writ small>' What he means by this is that the situation we can observe on the micro level on Easter Island is happening on the macro level the world over. Humanity's continued destructive use -- and pure destruction, in many instances -- of the Earth's natural resources could leave the entire human race without the many things in nature that we are now dependent on for our way of life. There are many complex and subtle similarities in this situation as well; this broad generalization only shows the broad parallelism that exists between the situation on Easter Island and the current situation of global environmental destruction.

Easter Island became a problem because of rampant, unplanned use of resources and because of the destruction of those resources through unplanned secondary effects (i.e. rats chewing on palm seeds). The same thing is happening in many different specific instances with humanity. Oil is a resource that both destroys through its emissions (an unplanned secondary effect), and is also not renewable. Eventually, we will be left without oil as an energy source and with all of the detrimental effects of its centuries of use......