Process by which an early metazoan embryo becomes a gastrula, acquiring first two and then three layers of cells.
Ameboid movement is a form of movement especially characteristic of amebas and other unicellular forms; it is also found in many wandering cells of metazoans, such as white blood cells, embryonic mesenchyme, and numerous other mobile cells that move throu
Bilateral nervous systems, the simplest of which occur in flatworms, represent a distinct increase in complexity over the nerve net of radiate animals.
Horticulture may be described as the practice of growing plants in a relatively intensive manner. This contrasts with agriculture, which, in most Western European countries, relies on a high level of machinery use over an extensive area of land
A biome is a major biotic unit bearing a characteristic and easily recognized array of plant life. Botanists long ago recognized that the terrestrial environment of the earth could be divided into large units having a distinctive vegetation, such as fores
The biosphere as usually defined is the thin outer layer of the earth capable of supporting life. It is probably best viewed as a global system that includes all life on earth and the physical environments in which living organisms exist and interact.
Microorganisms isolated from different sources (soil, water and air) or genetic manipulation are cultured on growth media.
The area of developmental genetics has also received major attention of geneticists in recent years to answer questions like the following. What are the relative roles of nucleus and cytoplasm in differentiation?
Germplasm theory of Weismann was a very significant advancement in our understanding of heredity, since this was for the first time that a distinction between hereditary and environmental variations could be made on a sound basis.
Mutations are heritable changes in the genetic material that give rise to alternative forms of any gene. These alternate forms are called alleles. There are two broad types of mutations, those that affect the gene and those that affect whole chromosomes (
Among all living organisms, flowers, which are the reproductive structures of angiosperms, are the most varied physically and show the greatest diversity in methods of reproduction of all biological systems.
In vertebrates, the actual tissue from which gonads arise appears in early development as a pair of genital ridges, growing into the coelom from the dorsal coelomic lining on each side of the hind-gut near the anterior end of the kidney (mesonephros).
Column chromatography is one of many forms of chromatography. Others include paper, thin-layer, gas, and HPLC. Most forms of chromatography use a 2-phase system to separate substances on the basis of some physical-chemical property.
Packed inside an insect no bigger than a jellybean is a venom strong enough to cause intense pain in humans - and occasionally death, in people who are allergic to it.
The Chloroflexi (Chlorobacteria) are a class of bacteria that produce energy through photosynthesis. They make up the bulk of the filamentous anoxygenic phototrophs
Plants appeared on land about 425 million years ago and the evolutionary history of the plant kingdom reflects increasing adaptation to the terrestrial environment. Plants have organs and organ systems.
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