Innate and adaptive immunity
Essay - 7 pages - Biology
Immunology has roughly been split into two major subdivisions: cellular immunity, which comprises all different immunocompetent cells, and humoral immunity, a collection of all molecules involved in immune processes, such as cytokines, immunoglobulins, complement factors, and many others. Serum...
Bark beetles
Essay - 7 pages - Biology
Bark beetles are small, dark, cylindrical beetles, usually less than 7mm long. As their name implies, they are usually associated with woody plants. Despite their small size and modest appearance, they have an intriguing assemblage of feeding and breeding habits, some of which result in...
Agroforestry
Essay - 6 pages - Biology
Agroforestry is a term for practices where trees are combined with farming, as well as for the interdisciplinary subject area embracing land use systems, at a range of scales from that of the ?eld to the planet, that involve interactions amongst trees, people, and agriculture. Put simply,...
Biodiversity in forests
Essay - 7 pages - Biology
Interest in biodiversity began in the mid-1980s with the Biodiversity Symposium, held in Washington, DC, sponsored by the National Academy of Science. Within increasing human populations and rising demands for resources and living space, the need to conserve biological diversity rose to the...
Regulation of pigment biosynthesis in flowers
Essay - 9 pages - Biology
Flower color, along with fragrance, floral shape and nectar reward, is important to the interaction between plants and pollinators; and preferences towards specific colors are exhibited by pollinators, whether they are birds, bees, butterflies or other insects. Commonly contributing to floral...
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....
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. There are several...
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...
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...
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...
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...
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...
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...
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...
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...
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...
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...
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...
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...
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...
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...
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...
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...
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...
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 GABAA receptors,...
Unilateral lesions of the Nigrostriatal pathway
Tutorials/exercises - 20 pages - Biology
The nigrostriatal system through the basal ganglia is essential for regulating motor movement. Normal motor behavior requires a delicate balance between the excitatory direct pathway and the inhibitory indirect pathway modulated by the D1 and D2 receptors, respectively. Unilateral destruction...
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...
Skeletal Radiology and Bone Growth
Tutorials/exercises - 4 pages - Biology
Radiographic examination is the key to the diagnosis of many skeletal abnormalities. It is essential that each bone be examined in its entirety, including the cortex, medullary canal (cancellous bone or spongiosa), and articular ends. The position and alignment of joints are determined. In...
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...
Novel pressure-relief wheelchair: research paper
Tutorials/exercises - 30 pages - Biology
Pressure sores are painful and debilitating tissue wounds which commonly affect wheelchair users. Current treatment of pressure sores requires bed-rest for up to sixteen weeks, which is unacceptable for patients with active life-styles. The purpose of our project is to design a wheelchair that...
