Involve the use of population-based statistical methods of data collection and analysis to elucidate and predict the patterns of development and distribution (including associated casual factors) and potential control, of disease across and within populations. See Epidemiology, Fetal programming, Hazard ratio, Odds ratio, Rate ratio
Author Archives: Brian Hopkins
Enzyme
A biological catalyst produced in cells and capable of speeding up and specifying chemical reactions essential for life. A globular protein, it is specific to a particular reaction or group of similar reactions, and therefore there are a great number of them. The exact mechanism by which enzymes act is not fully understood, but it …
Ependymal cell
A type of glial cell (sometimes referred to as ‘neuroglial’) that makes up the lining membrane of the ventricles of the brain and of the central canal of the spinal cord, as well as the ependymal area of the neural tube. Recently discovered to be neural stem cells that provide neuronal and glia cell precursors. …
Environmental tobacco smoke (ETS)
Otherwise known as ‘second hand smoke’, which refers to exposure of non-smokers to tobacco smoke in the environment, and which is considered to be a risk for pregnant mothers. See Alveoli, Attributable fraction, Carcinogen, Cardiovascular accidents, Emphysema, Mesencephalic reticular activating system, Nicotine, Polycyclic aromatic hydrocarbons, Prospective cohort, Risk factors Vasoconstriction
Environment
In ecology, it is the sum total of biological, chemical and physical factors in some circumscribed area. It really only exists because it is inhabited by an organism. For example, a field is an environment for a horse, its droppings the environment for beetles and their exoskeletons the environment for parasitic mites. Thus, the field …
Environment of evolutionary adaptedness
A term devised by John Bowlby (1907-1990) in the context of the Bowlby-Ainsworth theory of attachment to denote the environment to which a species has become adapted during its phylogenetic history such that, for example, a system of maternal behavior co-evolved with a complimentary system of infant attachment behaviors, thus ensuring protection for young organism …
Entropy
Introduced into classical thermodynamics by Rudolf J. Clausius (1822-1888), the term refers to a state of disorder or a quantitative measure of it. According to the second law of thermodynamics, closed systems evolve spontaneously toward a state of maximum entropy or disorder. In such a disorganised state, energy is evenly distributed throughout a system, with …
Entoderm (or endoderm)
The innermost primary germ layer that originates during gastrulation, which gives rise to the alimentary tract and other internal organs of the body. See Blastopore, Blastula, Differentiation (embryology), Ectoderm, Embryo, Epithelium, Gastrulation, Germinal (or germ) layers, Invagination, Mesoderm, Organogenesis, Pancreas, Pharyngeal arches
Entorhinal cortex
Located in the rostral half of the ventromedial surface of the temporal lobe, the entorhinal cortex (EC) is part of the hippocampal formation, with the other areas being the hippocampus proper, the dentate gyrus and the subiculum. Its name derives from the fact that its location is inside the rhinal sulcus in the olfactory area. …
Endothelium
Originating in the mesoderm, it is a single, thin layer of flattened polygonal cells lining the interior surfaces of the vertebrate heart, blood and lymph vessels. In fact, endothelial cells line the entire circulatory system. These cells are involved in blood clotting, the formation of new blood vessels, and the control of blood pressure (vasoconstriction …