Biology/circadian rhythm
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Question
Is a biological day the same as a subjective day?
Hi Taeko: Thanks for your question.
Circadian rhythms are sleep/wake cycles that are endogenous to a species. The rhythm is linked to the day-night cycle and is reset as the cycle changes.
The freerunning rhythm of many blind people or people with sleep disorders cannot be entrained to a 24 hour cycle and the sleep-wake schedule is shifted daily. I guess that's what you mean by a subjective day.
The biological day is when the sleep-wake cycle matches the day-night cycle.
Is that what you mean?
Here are some links:
http://en.wikipedia.org/wiki/Circadian_rhythm
http://en.wikipedia.org/wiki/Free-running_sleep
http://en.wikipedia.org/wiki/Non-24-hour_sleep-wake_syndrome
Hope this helps!
FM Rollwagen, PhD
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Answers by Expert:
Florence M Rollwagen
Expertise
I can answer questions in biology, microbiology and immunology on the undergraduate or graduate level. I can also address medical and health concerns regarding alternative medicine, autoimmune diseases (lupus, MS) liver disease and intestinal problems.
Experience
I have over 20 years experience in research and teaching at the medical/graduate level, and 5 years teaching college biology and microbiology. My expertise is in microbiology and immunology, specifically the biology of cytokines and soluble immune response modifiers. I also carried out original research in blood substitutes and shock/trauma.
Organizations
American Association of Immunologists (AAI)
American Association for the Advancement of Science (AAAS)
Publications
Journal of Experimental Medicine, Journal of Immunology, Cytokine, Shock, Experimental Hematology
Education/Credentials
BS biology 1966
MS biology 1968
PhD immunology 1979
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