The Appearance of Sleep Spindles and K Complexes Is a Clearsign

question 309

True/False

The appearance of sleep spindles and K complexes is a clearsign that the sleeper is in stage 2 NREM sleep.

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Definitions:

Valence Electrons

The electrons in the outer electron shell, known as the valence shell, of an atom; in the formation of a chemical bond, an atom can accept electrons into its valence shell or donate or share valence electrons.

Isotopes

Variants of a particular chemical element that differ in neutron number, and consequently in mass, but not in chemical properties.

Radioisotope

A radioactive isotope of an element, used in various scientific applications including medicine and radiometric dating.

Stable Isotope

A non-radioactive form of an element’s isotope, which does not change or decay over time.