The point at which the mass of a rigid body can be considered to be concentrated. More technically, it is the point from which the sum of the moments of inertia of all parts of the body is zero. The centre of mass is not always located in the body as it is dependent of …
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Cell theory
In its modern form, the theory that all cells come from previously existing cells and that they are the fundamental functional units of all living organisms. Considered to be one of the most important theories in biology, it was originally proposed by Matthias Schleiden (1804-1881) in 1838 and again the following year by Theodor Schwann …
Center of gravity
A fixed point on a rigid body through which the resultant force of gravity always passes, regardless of the position of the body. In a uniform gravitational field, it is identical to the center of mass. Thus, for practical purposes, the center of gravity and center of mass coincide. In strict physical terms, however, there …
Cell recognition molecules
Particular proteins or other complex molecules generated by one cell type that another cell type has receptors for and can ‘recognise’ (i.e., receptor uptake of these molecules causes some change in the cell’s physiology, usually by genetic instruction). They mediate cell-cell and cell-extracellular matrix interactions. It appears that are a very large number of genes …
Cell locomotion
The ways in which cells move differ between eukaryotes and prokaryotes. For eukaryotes, most mechanisms seem to involve protein tubules or filaments sliding past one another and generating force. However, how such force is generated is not well understood, but adhesion molecules including integrins are involved. See Adhesion molecules, Axon pathway selection, Cell migration, Eukaryote …
Cell migration
During early development, neurons migrate along a short and direct route, using a transient population of radial glial cells as a sort of scaffolding. Later, however, as the cerebral cortex begins to fold, the route becomes longer and more complex, the later migrating neurons assuming positions external or more superficial to those that arrived earlier. …
Cell assemblies
A group of neurones that act together in processing a certain task. One neuron can be part of several cell assemblies Donald O. Hebb (1949), in his book The organization of behavior: a neuropsychological theory, introduced the notion of cell assemblies into psychology. According to him, stimuli, objects, but also more abstract psychological entities (e.g., …
Cell death
Programmed cell death or apoptosis is the patterned elimination of specific cells or tissues that occurs as a normal process during early development. It is particularly evident during prenatal development of the central nervous system. See Apoptosis (or cell death), Lysosomes, Olfaction, Synapse elimination
Cell adhesion molecules (CAMs)
Heterophilic Homophilic interaction: adhesion between two copies of the same adhesion molecule. Heterophilic interaction: binding between an adhesion protein and some other molecule. See Adhesion molecules, Alzheimer’s disease, Cadherins, Cell, Cell recognition molecules, Growth cone, Immunoglobins, Lamillipodia, Ligands, Morphogenesis, Mucins, Mutation (biology), Neural cell adhesion molecule (N-CAM), Neurite, Oligosaccharides, Selectins, Semaphorins, Synapse
Cause (or causal factor)
The agent that activates or brings about change in a behavior mechanism. See Behavior mechanism, Causalo determinism (or causalism), Causal pathway, Causality (in philosophy), Control parameter