Okuma AnlamaSoru #11110
The Biology of Circadian Rhythms
Circadian rhythms are 24-hour cycles that govern essential physiological processes in virtually all living organisms, from single-celled algae to humans. In mammals, the central pacemaker orchestrating these rhythms is the suprachiasmatic nucleus (SCN), located within the hypothalamus. The SCN relies heavily on photic signals received from specialized retinal ganglion cells to synchronize the body's internal clock with the external day-night cycle. This internal timing mechanism regulates core body temperature, hormone secretion such as melatonin and cortisol, and metabolic rate. Chronic disruption of circadian rhythms—common among shift workers and excessive nocturnal screen users—has been linked to elevated risks of obesity, cardiovascular disorders, and depression. According to the passage, the body's internal biological clock is primarily synchronized by ----.
- A)intense physical exercise conducted before bedtime
- B)the strict timing of heavy protein-rich meals
- C)natural environmental light cues perceived through the eyes
- D)ambient temperature fluctuations during winter months
- E)total isolation from all digital communication screens
Cevabı ve çözümü göster
Doğru cevap: C) natural environmental light cues perceived through the eyes
Çözüm: Metinde sirkadiyen ritmin ana senkronizasyon aracının göz yoluyla algılanan ışık sinyalleri (environmental light cues) olduğu vurgulanmıştır. Doğru cevap C'dir.