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Moderate

Circulatory System Specializations

APBIO-JLNS2D

When a high school athlete goes out for a run, the capillary beds surrounding the lungs and the capillary beds within large muscle groups will dilate while capillary beds surrounding the digestive tract will constrict.

Additionally, the blood pressure in the capillary beds surrounding the lungs must be adjusted independently of the blood pressure of the capillary beds within the large muscle groups. This is true for all mammals.

For this type of regulation to be possible, which of the following is required?

A

An open circulatory system.

B

The use of myoglobin as a respiratory pigment.

C

The presence of a lymphatic system.

D

A four-chambered heart.