?

AP® Biology

Free Version

Upgrade subject to access all content

Difficult

Hemoglobin Function Data Analysis

APBIO-TFKV2V

Hemoglobin, the protein found in red blood cells that is responsible for the transport of oxygen from the lungs to cells in the body, is made up of four polypeptides. Each polypeptide has an active site when oxygen can bind.

Several factors affect hemoglobin's ability to bind and hold oxygen in the active sites of each polypeptide. Examine the data table below, which tracks hemoglobin's ability to hold oxygen in its active sites.

Percentage of maximum oxygen-binding capacity of hemoglobin Blood pH
20% 7.0
40% 7.1
60% 7.2
80% 7.3
100% 7.4

$\ $

Based on this information, which of the following statements is MOST accurate?

A

The pH of blood in the capillaries near the lungs is probably higher than the pH of blood in the capillaries near active muscle cells.

B

The pH of blood in the capillaries near the lungs is probably lower than the pH of blood in the capillaries near active muscle cells.

C

The pH of blood in the capillaries near the lungs is probably the same as the pH of blood in the capillaries near active muscle cells.

D

The pH of blood in the capillaries near the lungs is probably monitored and adjusted by the hypothalamus based on blood oxygen levels.