biological rhythm
31sex — /seks/, n. 1. either the male or female division of a species, esp. as differentiated with reference to the reproductive functions. 2. the sum of the structural and functional differences by which the male and female are distinguished, or the… …
32Circadian — Refers to events occurring within a 24 hour period, in the span of a full (24 hour) day, as in a circadian rhythm. The word “circadian” is a 20th century invention. It was coined in 1959 from the Latin “circa” (around) + “diem” (a day). However,… …
33migration — migrational, adj. /muy gray sheuhn/, n. 1. the process or act of migrating. 2. a migratory movement: preparations for the migration. 3. a number or body of persons or animals migrating together. 4. Chem. a movement or change of position of atoms… …
34jet lag — jet lagged, adj. a temporary disruption of the body s normal biological rhythms after high speed air travel through several time zones. Also, jetlag. [1965 70] * * * Period of adjustment of biological rhythm after moving from one time zone to… …
35Richter, Curt Paul — born Feb. 20, 1894, Denver, Colo., U.S. died Dec. 21, 1988, Baltimore, Md. U.S. biologist. He received a Ph.D. from Johns Hopkins University. He introduced the concept of the biological clock in a 1927 paper on animals internal cycles (see… …
36Homeostasis — (from Greek: ὅμος, hómos , equal ; and ιστημι, istēmi , to stand lit. to stand equally ; coined by Walter Bradford Cannon) is the property of either an open system or a closed system, especially a living organism, that regulates its internal… …
37Daylight saving time — This article is about daylight saving time in general. For DST in a specific location, see Daylight saving time by country. Summer time and DST redirect here. For other uses, see Summer time (disambiguation) and DST (disambiguation) …
38animal learning — ▪ zoology Introduction the alternation of behaviour as a result of individual experience. When an organism can perceive and change its behaviour, it is said to learn. That animals can learn seems to go without saying. The cat that… …
39Guinea pig — For the domestic pig breed, see Guinea Hog. For other uses, see Guinea pig (disambiguation). Guinea pig …
40Philippine Tarsier — ] status = NT status ref =IUCN2006 | assessors = Eudey, A. Members of the Primate Specialist Group | year = 2000 | title = Tarsius syrichta | id = 21492 | downloaded = 2006 05 12] trend = unknown status system = iucn3.1 image width = 299px regnum …
