Alone in the woods, Pedro hears a noise. He thinks he sees a bear coming toward him. His heart starts pounding and then, a moment later, he realizes how frightened he is. This sequence of events is BEST explained by the theory of emotion.

Explanation:

According to Cannon-Bard theory, all the emotional expressions occur due to the stimulation of hypothalamic structures present in brain. This theory also states that feeling and physiological effects of an emotional stimuli occurs simultaneously.

Here, James thinks that a bear is coming, this is a stimulus. His heart starts pounding that is the physiological effect of the stimulus and the next moment he feels frightened which is a feeling.

So we conclude that in this case, the physiological effect and feeling of emotion occurred simultaneously. So these sequence of events is best explained  by Cannon-Bard's theory.

many other transport proteins, often called pumps, move materials against a concentration gradient. active transport drives molecules across a membrane from a region of lower concentration to a region of higher concentration. this process, shown in figure 5.1, uses transport proteins powered by chemi- cal energy.

colors do exist. the color of the sky is actually violet; humans percieve the color of the sky as blue.