Reference no: EM133567544

Question

1. Light signals reach the suprachiasmatic nucleus via the:

Ponto-geniculo-occipital path

Pineal gland

Homunculus

Retinohypothalamic tract

2. In the absence of light signals, circadian rhythms of activity:

Devolve into 4 - 8 hour cycles

Cease to exist

Switch from the suprachiasmatic to the reticular system

Continue with a period slightly more or less than 24 hours

3. When delivered at the appropriate time in the circadian cycle, a pulse of light can:

Shift the cycle earlier or later

Eliminate activity but not temperature rhythms

Cause temporary blindness

Cause a mutation in the suprachiasmatic nucleus

4. If the suprachiasmatic nucleus is lesioned, the sleep rhythms of rats:

Are replaced by a continuous coma state

Are controlled by the reticular system

Devolve into 4 - 6 hour cycles

Continue in their normal fashion

5. Hamster A has a normal circadian rhythm of 24.2 hours. Hamster B has a mutant rhythm of 20 hours. The suprachiasmatic nucleus of Hamster B is lesioned. The suprachiasmatic nucleus of Hamster A is removed and implanted in the fourth ventricle of Hamster B. The circadian rhythm of Hamster B will be:

20 hours

Somewhere between 24.2 and 20 hours

Devolved into 4 - 6 hour cycles

24.2 hours

6. One way of measuring circadian phase (whether you are an owl or lark) is the:

Birdsong Scale

Horne-Ostberg Scale

Multiple Sleep Latency Test

Nocturnal Oxygen Saturation Monitor

7. A variety of evidence supports the theory that circadian phase preferences are strongly influenced by:

Diet

Genetics

The latitude where you live

Your job