Sentence:  Although in both emotions sympathetic symptoms <WSD>are</WSD> present , different autonomic somatic patterns underlie aggression and anxiety , respectively , as indicated by the rate of the excretion of the catecholamines , the state of the muscle tone , and the Mecholyl test . 
Meaning of the word marked with <WSD> tags:  have the quality of being; (copula, used with an adjective or a predicate noun)