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19 Nov 2008
doc

Cytokines and chemokines

Essay - 5 pages - Biology

Cytokines are soluble low-molecular weight glycoproteins or small polypeptides that act in an autocrine or paracrine manner between leukocytes and other cells. Cytokines have many biologic functions and are important for leukocyte growth and differentiation as well as activation and migration....

19 Nov 2008
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Reproductive ecology of forest trees

Essay - 8 pages - Biology

Plant reproductive processes encompass biotic interactions, such as pollination and seed predation and dispersal, and abiotic elements, notably disturbance that creates differential reproductive opportunities for plant groups and thereby maintains diverse forest formations. ...

18 Nov 2008
doc

Forest canopies

Essay - 12 pages - Biology

The word canopy is derived from the Latin conopeum, describing a mosquito net over a bed. For canopy researchers in many tropical and temperate forests, this derivation is all too ?tting. Forest canopies are home to perhaps 50% of all living organisms, many of which are uniquely specialized for...

17 Nov 2008
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Vernalization

Essay - 4 pages - Biology

The term vernalization is derived from the Latin word vernus meaning ‘of the spring'. Vernalization was defined as ‘the acquisition or acceleration of the ability to flower by a chilling treatment'. The promotion of flowering by vernalization is the result of subjecting an imbibed seed...

17 Nov 2008
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Vernalization requirement and vernalization response

Essay - 6 pages - Biology

The major loci controlling vernalization requirement in the diploid wheat Triticum monococcum are VRN1 and VRN2 (in cereals the VERNALIZATION, VRN, designation applies to genes conferring a vernalization requirement and differs from Arabidopsis genes of the same name that are involved in...

17 Nov 2008
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Flower senescence

Essay - 4 pages - Biology

Flowers, no matter their size, shape, color or structure, have one important function for plants: sexual reproduction. Sexual reproduction consists of several distinct developmental processes including pollen production, ovule formation, and pollination, fusion of gametes and the development and...

17 Nov 2008
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Timing of senescence: The opening act

Essay - 4 pages - Biology

Flower senescence in this context will happen when it becomes more advantageous for the plant to construct a new flower - including renewed odds of getting pollinated - than to maintain an existing one. Flower senescence can therefore be defined as the events that lead to the death of flower...

17 Nov 2008
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Developmental control and biotechnology of floral pigmentation

Essay - 7 pages - Biology

For many angiosperms, pigment formation is a key part of flower development. At least 200 plant genera contain species that show color change during flower development. Thus, variation in flower color associated with a change in nectar and pollen availability may be a common occurrence. The...

17 Nov 2008
doc

Regulation of floral organ-identity gene expression

Essay - 5 pages - Biology

A key advance in the field of flower development has been the uncovering of a direct role for the FM-identity gene LEAFY (LFY) in activation of the floral organ-identity genes. LFY encodes a novel plant-specific DNA-binding protein that can bind in vitro to the promoters of several floral...

17 Nov 2008
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Molecular biology of floral organogenesis

Essay - 4 pages - Biology

In the early 1990s, genetic studies on Arabidopsis thaliana and Antirrhinum majus led to the isolation and characterization of floral organ-identity genes (also called floral homeotic genes) and the establishment of the seminal ABC model for flower development. This model proposed that different...

14 Nov 2008
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Biotechnology of floral development

Essay - 8 pages - Biology

The understanding of floral development at a molecular level has proceeded at an unprecedented rate. Molecular genetic studies on two model plants, Antirrhinum and Arabidopsis in particular, have provided the foundation for this progress through the initial identification of genes involved in...

11 Nov 2008
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The molecular biology of apomixis

Essay - 6 pages - Biology

Apomixis is the subject of a number of recent reviews. Some authors have focused on the potential agronomic and economic benefits of apomixes. Others have discussed the developmental and genetic basis of apomixes or reviewed current theory regarding the evolutionary and ecological implications of...

11 Nov 2008
doc

Flower origin

Essay - 4 pages - Biology

Since the identity of floral organs is specified by conserved floral organ-identity genes, clarifying the phylogeny of these genes and their protein products may provide us with valuable insights into the evolution of flowers. Analysis of numerous MADS box genes from mosses and ferns suggested...

11 Nov 2008
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Physiology of Photoperiodism

Essay - 5 pages - Biology

Photoperiodism can be defined as the response to changes in day length that enables plants (or any other living organism) to adapt to seasonal changes in their environment. Except at the equator, the passage of the year is marked by a continuous but highly reproducible variation in the length of...

11 Nov 2008
doc

Genes regulating ovule development

Essay - 5 pages - Biology

Ovules are the precursors of seeds. More specifically, they are sporophyticstructures and the site of megagametogenesis or female gamete shape that culminates in the formation of the haploid embryo sac. The prototypical angiosperm ovule consists of three parts: (1) the nucellus, where...

11 Nov 2008
doc

Genetic engineering of plant cells

Essay - 5 pages - Biology

In this text, we shall see how selection data have been used to assist the design of experiments on the modification of plants using recombinant DNA (genetic engineering). It is evident that in some situations the potential of in vitro selection is limited by a number of difficulties. It is...

06 Nov 2008
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Improvement of plants via plant cell culture

Essay - 6 pages - Biology

The techniques of plant cell culture facilitate the rapid production of variant cell lines via selection procedures similar to those employed in microbial systems. These variant cell lines are useful in research into the genetics and biochemistry of plant cells and in biotechnology for production...

25 Sep 2008
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Isoenzymes of aspartate aminotransferase

Essay - 6 pages - Biology

The continued production of protein-based medicines and chemically-engineered enzymatic products necessitates further information about protein structure and function. An enzyme in a cell can have many functions or loci. To account for slight differences in reaction products or locations, an...

25 Sep 2008
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Protein analysis of Sea Urchin sperm cells

Essay - 8 pages - Biology

Cells express different gene products in order to achieve specialization and differentiation. Sperm are highly specialized to do nothing more than fertilize an oocyte, and they are thus an excellent candidate for research into cellular specialization.1 A terminally differentiated cell like a...

04 Aug 2008
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Benzodiazepine/ GABAA receptor characteristics

Essay - 9 pages - Biology

GABAA (?-aminobutyric acidA) receptors are recognized as the chief inhibitory neurotransmitter receptors in the mammalian central nervous system. The GABAA receptors are pentameric membrane proteins consisting of five subunits. The subunits can combine in different ways to form...

23 Apr 2008
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The Giant Panda

Essay - 3 pages - Biology

The Giant Panda, scientifically known as the Ailurodopa melanoleuca, is considered an endangered species found in a few mountain ranges in central China, Sichuan, Shannxi, and the Gansu Provinces, according to the Smithsonian National Zoological Park. The Smithsonian Zoo continues to add that...

19 Feb 2008
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Analysis of an Association between Nicotine Dependence and Attention-Deficit/Hyperactivity Disorder

Essay - 5 pages - Biology

The goal of this paper is to evaluate the significance of the co-morbidity of nicotine abuse in adolescents afflicted with ADHD (Attention-Deficit Hyperactivity Disorder). Due to the nature of the disorder and its possible underlying pathophysiology of dopaminergic dysfunction, the use of...

19 Dec 2007
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Face Value: The Complexities of Genetic Engineering

Essay - 2 pages - Biology

Society is no stranger to technology - it has been adapting it and advancing it for decades. Technology has completely revolutionized the way we interact each other as well as ourselves. Due to this complete integration, there has been an addiction formulated. Human beings now thrive on...

19 Dec 2007
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Natural Selection vs. Divine Creation

Essay - 3 pages - Biology

From the beginning of the ideas presented by Charles Darwin in The Origin of Species, and their gaining support from the scientific community, the theory of evolution was been met with opposition. A great deal of this opposition came from religious groups who believed in a creation from a...

17 Dec 2007
pdf

Results and Figures of Salt on Germination and Growth

Essay - 3 pages - Biology

Finding the effects of salt on germination and growth of plants took twenty-two days of research. Each collection day the height, height of the leaf, color, height of the node, number of buds, and the number of the flowers were taken into account. Based on the original hypothesis stating that the...

17 Dec 2007
pdf

Brassica Rapa in Comparison With Sodium Chloride

Essay - 4 pages - Biology

In this study the Brassica Rapa will be tested to see if salt water effects it's growth. Data will be taken from four different types of groups: distilled water; 0.25% of sodium chloride; 1.00% of sodium chloride; and 4.00% of sodium chloride. Data will be collected in a twenty-two day span,...

27 Nov 2007
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The Social History of LSD

Essay - 4 pages - Biology

When Albert Hofmann created LSD 25 during experimentation in his laboratory, he had no idea what was to become of it, or what kind of an impact it would have. "Dr. Humphry Osmond invented the term 'psychodelic', which was later amended to 'psychedelic to get rid of the nuthouse...

27 Nov 2007
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The ccr5-delta 32 genetic mutation and human evolution - published: 27/11/2007

Essay - 2 pages - Biology

Genetic mutations are not uncommon. They can happen for a variety of reasons and have a variety of effects. Those with negative effects are weeded out by natural selection, and those with positive effects prevail and are accumulated due to natural selection. These...

26 Nov 2007
doc

Venomous Lizards

Essay - 2 pages - Biology

The two venomous lizards of the world are impressive creatures about which much misinformation has been spread for centuries. They have been thought to possess supernatural features such as poisonous breath, a stinging tail and the ability to spit their venom. The Gila monster (Heloderma...

02 Oct 2007
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Not 'To Study or Not to Study,' But How?

Essay - 5 pages - Biology

To highlight what constitutes the foundation of Man, anthropologists, ethnographers, and theologians like Jonathan Smith, Claude Lévi-Strauss, and Clifford Geertz constantly study “savage” societies, societies very different from our own. Scholars endlessly debate which characteristics...