Answer to Question 1
Answer: The two-factor theory is a two-stage model that explains how we make attributions about our internal experience. First we must experience arousal. Second, if we are not sure about the source of the arousal, we seek an appropriate explanation to help us label what we're feeling. Once we're aroused and seek an appropriate label, we often look to the external environment, including other people, to decide what we're feeling. For example, some participants in Stanley Schachter and Jerome Singer's (1962) experiment had no explanation for why they were feeling aroused, and looked to an experimental confederate to figure out how they were feeling. When the confederate acted silly and happy, they labeled their arousal as a positive emotion; when he acted angry, they labeled their arousal as a negative emotion.
Answer to Question 2
Answer: First, although we are generally better at deciding how we feel than why we feel that way, we may not always be accurate; sometimes we tell more than we can know about how we feel. When it comes to introspecting about reasons for our thoughts, feelings, and behaviors (e.g., why we like someone), the very act of introspection can change those attitudes, feelings, and behaviors. The consequent reasons-generated attitude change arises because we might identify the most readily accessible reasons that seem plausible. And what is most accessible at any one point in time might be an attitude or feeling that is different from what we felt before.
Polyploidy has been an important factor in the evolution of plants.
Signal Detection Theory
Vienna: Social Structure and Social Interaction
The clonal selection theory of the adaptive immune response
Sternberg's theory postulates three components of love
Some Cofactors in Biological Systems