Named after its discoverer, the biochemist Hans A. Krebs (1900-81), it is a series of biochemical reactions essential to the metabolism of aerobic organisms. The enzymes of the cycle are located in the mitochondria and work in close association with the various components of the electron transport chain. It involves interconversions of various acids, with …
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Here kinetics is taken to include two connected notions: kinetics as addressed in physics and linked rigid-body kinetics. The first version means the study of the determinants of motion, while the second refers to the movement of interconnected bodies under the action of external forces. Transferred to the human body, the latter treats ‘bodies’ as …
The energy, measured in joules, a body possess by virtue of its motion and which is equal to work a body would do if brought to rest. A body of mass m (kilograms) with speed v (meters per sec.) has translational (or classical) kinetic energy T=1/2mv2. In contrast, a rotating body with a moment of …
Progressive movement of an object against a background involving deletion or accretion of texture elements as one surface covers or uncovers another. Perceiving this visual obstruction is a reliable depth cue, producing depth perception even in situations with minimal information, a topic pursued intensely by adherents of Gibsonian ecology psychology. Variations of this set-up whereby …
Visual information from object or surface movement that specifies its relative distance to the observer. Associated with this phenomenon is the kinetic depth effect (KDE) discovered by Wallach and O’Connell (1953). As with other depth cues, it is usually produced in combination with other effects such as motion parallax. When rotating visual information is projected on …
The interdisciplinary study of physical activity. Originally employed as a term describing the study of movement using the principles of mechanics and anatomy. The term derives from kines meaning movement and ology the study of something. Today, the term is used to define an academic area of study of human movement broadly defined (i.e., …
A general term used to describe sensations associated with movement arising from receptors in the muscles, tendons, joints and skin. Used interchangeably with proprioception. While it is more or less synonymous with proprioception, James J. Gibson included the visual modality (i.e., the act of seeing) under proprioception. See Body awareness, Cerebellum (functions), Feedback, Proprioception
Studies of object motions and their relationships to reference frames that may involve the relative motions of other objects, but without regard to cause. Two types of constrained motion in which objects move along constrained trajectories are addressed by kinematics: motion with a constant velocity and motion with constant acceleration. What also distinguishes it from …
A term used differently in different countries, especially on mainland Europe, but most commonly refers to pre-school centers providing some educational input immediately in the year or two immediately preceding formal schooling and which may be part-time or full-time. See National Curriculum (education UK), Nursery school, Preschool children, Toddlers
The specific characteristics of chromosomes in the nucleus of a somatic cell or organism in terms of their number, sizes and shapes. In humans, the karotype consists of 46 chromosomes while for crayfish, fruit flies and mice the numbers are 200, 8 and 40, respectively. See Chromosome, Down’s syndrome, Edwards syndrome, Karyotyping