c. Facial expressions coupled with effective responses
Explanation:
Emotions are an important aspect of human life. Research on emotions has produced several discoveries which led to important real world applications.
- an emotion is the result of the arousal as experienced
- universal facial expressions of seven emotions
- anger, contempt, disgust, fear, joy, sadness, and surprise
- when emotions are experienced even a blind person produces the same facial expressions
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Regulate body functions, promote growth, And repair tissue
They all work in different ways but they all work together. For example, the Skeletal and muscular system will help you move away from danger or fire. Although, the nervous system sends messages to the brain that there is danger or fire.
I believe most books are considered secondary sources.