Lung tissue receives oxygen and nutrients from the A) pleural ...

[swpotter12]

Lung tissue receives oxygen and nutrients from the
 A) pleural arteries.
  B) pulmonary arteries.
  C) pulmonary veins.
  D) coronary arteries.
  E) bronchial arteries.

Question 2

List the different types of adrenergic receptors, the responses they produce, and by what mechanisms.

[debra928]

Answer to Question 1

E

Answer to Question 2

There are two types of alpha receptors and two types of beta receptors. The alpha-1 receptor produces excitation or stimulation of metabolism. It works by activation of an enzyme and/or by release of calcium ion from internal stores. The alpha-2 receptor is inhibitory on its target cell by reducing the level of cAMP. Beta-1 receptors are stimulating and/or lead to increased energy consumption. They activate cellular enzymes. Beta-2 receptors inhibit activity or produce relaxation in smooth muscle cells. They operate through enzyme activation.

[swpotter12]

Thanks

[debra928]

Welcome