1) describe the pleura and explain its role in respiration.
2) what is the ens, and when was it discovered? what is its significance, what is its
nickname, and what are the characteristics that justify that nickname?
3) chemical reactions that require an input of energy are said to be ________.
4) what makes vegetable oils with trans fats similar in structure to saturated animal
fats? which type of fat is harmful, and in what way?
5) the two varieties of adrenergic receptors are ________ and ________.