Final answer:
The subjective experience of terror upon seeing a snake is an emotion, involving both physiological arousal and a cognitive appraisal according to various theories such as James-Lange and Schachter-Singer.
Step-by-step explanation:
The subjective experience of terror you have upon seeing a snake is referred to as an emotion. An emotion is a complex psychological state that involves a subjective aspect, which is your personal experience of the feeling, combined with a physiological response, expressions, and a cognitive appraisal of the situation. According to various theories of emotion, such as the James-Lange theory, the physiological arousal experienced upon encountering a threat like a snake is crucial for the emotion of fear to occur. Similarly, the Schachter-Singer two-factor theory of emotion emphasizes both physiological arousal and the cognitive labeling of that arousal in a particular context to result in an emotion. In contrast, a mood is a longer-lasting affective state that is less intense and less specific to a stimulus, and sensations are basic experiences derived from the senses.