Related Experiment Video
Updated: Feb 9, 2026

A Method of Trigonometric Modelling of Seasonal Variation Demonstrated with Multiple Sclerosis Relapse Data
Published on: December 9, 2015
Seasonal variations in oviductal morphology of the painted turtle, Chrysemys picta
Vicki Abrams Motz1, Ian P Callard1
1Department of Biology, Boston University, Boston, Massachusetts 02215.
Abstract:
Histology of each of the five segments of the oviduct of the female turtle Chrysemys picta was described for successive intervals throughout their annual cycle. Uterine and glandular segments showed marked seasonal variations in the extent and content of the submucosal and epithelial glands. Submucosal glands were most prominent in preovulatory and postovulatory animals (May to June), regressing in late summer (oviposited animals) and recrudescing the following spring. These changes correlated with variations in the muscularis layer, the number of uterine epithelial blebs, oviductal vascularity, and the presence of eosinophils in cervical segment cross-sections. These cyclic seasonal changes are discussed in relationship to reported seasonal changes in gonadal steroids in this species. Hormonal control was corroborated by oviductal response to estradiol-17β injected (1 mg/kg daily for 2 weeks) into mature, reproductively inactive (winter) animals. This treatment induced increases in glandular activity, vascularity, and distribution of eosinophils comparable to those of reproductively active (summer) animals.
Related Concept Videos
Seasoning of Wood
Achieving equilibrium moisture content is the goal of seasoning; this is the point where the wood's moisture content stabilizes to align with the moisture levels of the surrounding environment. Proper...
What is Variation?
The range, standard deviation, standard error, and variance are the different measures of variation.
Range: The range is the difference between its maximum and...
Biological Clocks and Seasonal Responses
Variation
When independent and dependent variables are plotted on a scatter plot, the slope of a line is a value that describes the rate of change between the two...
Conservative Site-specific Recombination and Phase Variation
The recognition sites for Cre recombinase called LoxP...
Variation of Atmospheric Pressure
Assuming the air temperature is constant at a given altitude and that the ideal gas law of thermodynamics describes the atmosphere to a good approximation, one can find the variation of atmospheric pressure with height.
Let p(y) be the atmospheric pressure at...

