Blood pH Reading Questions

Question #1

You test your pool water to find its pH. The test strip reads that the pH is 6.98. Is the water in your pool acidic, basic, or neutral? Use evidence from the reading to support your answer.The water in the pool is acidic. According to the box in the upper left corner of the reading, a pH less than 7 is acidic.

Review Information About pHpH below 7 is acidic

pH at 7 is neutralpH above 7 is basic

Question #2

What is the set point for human blood pH? Is this level acidic or basic?The set point for human blood pH is 7.40.

This level is considered basic.

Question #3

A person’s blood pH is found to be 7.25. Describe if this person’s blood will function properly, using the range for blood pH in your answer.No, the person’s blood will not function properly. In order for proper functioning, the range for blood pH is 7.35-7.45. Since 7.25 is not in this range, the body will have to correct the blood pH.

Question #4

What is the name of the primary molecule involved in blood pH regulation?

Carbon dioxide (CO2)

Question #5

Describe the effect of carbon dioxide on blood.

Carbon dioxide will lower the pH of blood, causing it to become acidic.

Question #6

How does the human body release carbon dioxide from the bloodstream?

The body releases extra carbon dioxide from blood by exhaling.

Question #7Fill in the chart for the responses to a change in blood pH.

An increase in carbon dioxide…Causes the blood pH to decrease (becomes acidic)…Which causes breathing rate to increase (breath faster).A decrease in carbon dioxide…Causes the blood pH to increase (becomes too basic)…Which causes breathing rate to decrease (breath slower).

Question #8

Describe how negative feedback is involved in regulating blood pH.When the blood pH gets out of range, regulatory responses will start and will continue until the set point is reached. Once the set point is reached, the regulatory response will stop.

Question #9Put the following events in the correct order:1. Billy starts to exercise so he uses energy.2. Billy’s cells undergo cellular respiration.3. Billy gives off CO2 as a waste product.

4. The pH of Billy’s blood is decreased. 5. The CO2 sensors in Billy’s blood send a message to his

brain to tell him that his CO2 levels are too high.6. Billy’s brain sends a message to his diaphragm.7. Billy’s breathing rate increases.8. Billy exhales CO2 at a greater rate.9. Billy’s blood pH level returns to its set point!

Question #10

Complete the chart, listing the organs involved in blood pH homeostasis, the system each organ belongs to and the organs’ function.

Blood Circulatory Transport

Brain Nervous Sends message to cause a change

Diaphragm Respiratory Contracts during breathing

Lungs Excretory Removes CO2 while exhaling

Organ System Function

Question #11

Draw and label the organs on the human body figure. Brain

Diaphragm

Lungs

Blood