Question

What is the significance of the rete mirabile in the heads of certain ungulate mammals?

a. it enables ungulates to sense small concentrations of chemicals that indicate the presence of mates or food.

b. it rids venous blood of toxins

c. it is a gas exchange structure that oxygenates blood before it enters the brain

d. it is a heat exchanger-its purpose is to cool the brain by exchanging heat with cool venous blood returning from the nasal cavity.

e. none of the above

Answer 1

The correct option is d. it is a heat exchanger-its purpose is to cool the brain by exchanging heat with cool venous blood returning from the nasal cavity.

The rete mirabile act as a heat exchanger. It exchanges heat, ions and gases between walls of vessel. Venous blood returns from the nasal cavity, which conducts cooled blood to the large venous sinuses at the base of the brain. The arterial blood is cooled in the venous sinuses before it enters the brain.