reproductive cycle

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cycle

 [si´k'l]
a succession or recurring series of events.
cardiac cycle a complete cardiac movement, or heart beat, including systole, diastole, and the intervening pause.
Cardiac cycle. From Applegate, 2000.
cell cycle the cycle of biochemical and morphological events occurring in a reproducing cell population; it consists of the S phase, occurring toward the end of interphase, in which DNA is synthesized; the G2 phase, a relatively quiescent period; the M phase, consisting of the four phases of mitosis; and the G1 phase of interphase, which lasts until the S phase of the next cycle.
citric acid cycle tricarboxylic acid cycle.
estrous cycle the recurring periods of estrus in adult females of most mammalian species and the correlated changes in the reproductive tract from one period to another.
hair cycle the successive phases of the production and then loss of hair, consisting of anagen, catagen, and telogen.
menstrual cycle see menstrual cycle.
ovarian cycle the sequence of physiologic changes in the ovary involved in ovulation; see also ovulation and reproduction.
reproductive cycle the cycle of physiologic changes in the reproductive organs, from the time of fertilization of the ovum through gestation and childbirth; see also reproduction.
sex cycle (sexual cycle)
1. the physiologic changes that recur regularly in the reproductive organs of nonpregnant female mammals.
2. the period of sexual reproduction in an organism that also reproduces asexually.
tricarboxylic acid cycle the cyclic metabolic mechanism by which the complete oxidation of the acetyl portion of acetyl-coenzyme A is effected; the process is the chief source of mammalian energy, during which carbon chains of sugars, fatty acids, and amino acids are metabolized to yield carbon dioxide, water, and high-energy phosphate bonds. Called also citric acid cycle, Krebs cycle, and TCA cycle.
 Central pathways of metabolism: How the body produces energy from the energy-containing nutrients using the tricarboxylic acid cycle. From Davis and Sherer, 1994.
urea cycle a cyclic series of reactions that produce urea; it is a major route for removal of the ammonia produced in the metabolism of amino acids in the liver and kidney.

re·pro·duc·tive cy·cle

the cycle that begins with conception and extends through gestation and parturition.

re·pro·duc·tive cy·cle

(rē'prŏ-dŭk'tiv sī'kĕl)
The cycle that begins with conception and extends through gestation and parturition.

cycle

a succession or recurring series of events.

cardiac cycle
a complete cardiac movement, or heartbeat, including systole, diastole, and the intervening pause.
The cycle includes eight separate phases: (1) isovolumetric contraction; (2) maximum ejection; (3) reduced ejection; (4) protodiastole (onset of ventricular relaxation); (5) isovolumetric relaxation; (6) rapid flow; (7) diastasis (onset of atrial contraction); (8) atrial systole.
cell cycle
the cycle of biochemical and morphological events occurring in a dividing cell population; it consists of the S phase, occurring toward the end of interphase, in which DNA is synthesized; the G2 phase, for gap 2, the interval between S and M; the M phase, for mitosis, consisting of the four phases of mitosis; and the G1 phase, which lasts from the end of M until the start of S phase of the next cycle. Fully differentiated cells are nondividing and are said to be in G0.
Enlarge picture
Cell cycle. By permission from Booth DM, Small Animal Clinical Pharmacology and Therapeutics, Saunders, 2000
citric acid cycle
estrus cycle
see estrous cycle.
Krebs cycle
ovarian cycle
the sequence of physiological changes in the ovary involved in ovulation. See also ovulation and reproduction.
reproductive cycle
the cycle of physiological changes in the reproductive organs, from the time of fertilization of the ovum through gestation and parturition. See also reproduction.
sex cycle, sexual cycle
1. the physiological changes recurring regularly in the reproductive organs of female mammals when pregnancy does not supervene.
2. the period of sexual reproduction in an organism that also reproduces asexually.
tricarboxylic acid cycle
urea cycle
a cyclic series of reactions that produce urea, a major route for removal of the ammonia produced in the metabolism of amino acids in the liver and kidney. See also urea.

reproductive

subserving or pertaining to reproduction.

reproductive behavior
see sexual behavior.
reproductive cycle
in all mammalian species other than humans the reproductive cycle is an estrous cycle.
reproductive efficiency
fertility or efficiency in terms of input, e.g. services per conception, bull serving capacity estimates.
reproductive failure
infertility; failure to produce viable offspring; the end-stage of reproductive inefficiency.
reproductive fitness
a pre-mating examination of cows in an intensive herd health program; includes manual examination of genitalia per rectum, cervical sample for microbiological examination, blood sample for locally relevant abortogenic diseases, manual examination of udder, milk cell count and composite bacteriological examination of milk.
reproductive history
computerized or card-based record of individual cow's complete breeding record including all services and identity of donor or naturally mated bull.
reproductive organs (female)
the ovaries, which produce the ova, or eggs; the uterine tubes; the uterus; the vagina, or birth canal; and the vulva, comprising the external genitalia. The udder is a secondary sex character, enclosing the mammary glands.
reproductive organs (male)
the testes, external genitalia and accessory glands that secrete special fluids and the ducts through which these organs and glands are connected to each other and through which the spermatozoa are ejaculated during coitus.
reproductive performance
the productivity of the animal or herd or flock in terms of offspring produced, can be expressed in many ways, e.g. live piglets per litter or per year or per sow-year or per cubic meter of shed space.
reproductive rate
viable, full-term offspring produced per female per year.
reproductive senescence
the end of cyclic reproductive activity in primates; not recognized in domestic animals.
reproductive system
the genital tract plus the endocrinal control systems, especially the hypothalamus, pituitary, gonads and placenta, the products of pregnancy and the mammary glands.
reproductive tract
see reproductive organs (above).
References in periodicals archive ?
of Haifa, Israel) notes that the life cycle of organizations is very similar to the biological life cycle, and uses that metaphor to discuss the problems and "diseases" that cause an organization to fail.
It has disrupted biological life cycles worldwide, triggering earlier plankton blooms in marine ecosystems and earlier spring migrations of species ranging from squid to birds (SN: 3/8/03, p.

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