Geoffrey is studying for a quiz on waking and sleeping. What should he know about the SCN?
What will be an ideal response?
Answers may vary. Here is a sampleGeoffrey should know that the body's internal master clock is the SCN in the hypothalamus. Input to the SCN comes from axons of special cells known as intrinsically photosensitive retinal ganglion cells (ipRGCs), which leave the optic nerve and project to the SCN, forming the retinohypothalamic pathway. Unlike other retinal ganglion cells (see Chapter 6), the ipRGCs do not process information about visual images. The ipRGCs contain a photopigment known as melanopsin that is related to, but different from, the other photopigments involved in vision. The SCN is active only during the day. The SCN helps animals distinguish between day and night, but other structures dictate whether an animal is nocturnal or diurnal in its behavior. Activity in the human SCN produces a response in the sympathetic nervous system, which in turn communicates with the pineal gland. As light decreases in the evening, accompanied by reduced SCN activity, less input from the sympathetic neurons allows the pineal gland to synthesize and release more melatonin, a neurochemical that modulates brainstem structures related to waking and sleep. The SCN also manages other sleep-related changes, including body temperature, hormone secretion, production of urine, and blood pressure changes. The SCN is not dependent on input from other structures to maintain its rhythms.
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A researcher is investigating the effects of exercise on weight. Identify the independent and dependent variables in this experiment
a) The dependent variable is weight; the independent variable is exercise. b) The independent variable is calories consumed; the dependent variable is diet. c) The independent variable is weight; the dependent variable is calories consumed. d) The dependent variable is amount of exercise; the independent variable is calories consumed.
________ is a legal term, not a psychiatric or psychological term
a. Insanity b. Psychopathology c. Associative disorder d. General adaptation syndrome e. Split personality
Ji Su was born with a rare genetic disorder. Doctors have carefully documented her case with MRIs, blood work, parent surveys, and behavioral observation. How would you classify the published article reporting on her condition?
A. naturalistic observation B. archival data C. case study D. participant observation
In proactive coping, people
A. remain unaffected and unmoved by both positive and negative experiences. B. anticipate and try to head off stress before encountering it. C. use wishful thinking to reduce stress. D. cope with stress by acting as if the stress were not even there.