HOMEOSTASIS WITHIN THE CIRCULATORY & RESPIRATORY SYSTEMS
AP BIOLOGY:
BIG IDEA #2 & #4
LEARNING GOALS
Identify how oxygen and carbon dioxide are transported and their effects on breathing rate.
Identify a dissociation curve and explain the role of partial pressure of oxygen and oxygen saturation in delivery of oxygen to the body.
Identify and explain how heart rate is controlled.
Identify changes in heart rate and connect to the function of the heart.
TRANSPORT OF GASES IN THE BLOOD: DIFFUSION
Gases diffuse because of differences in partial pressure!
CO2 AND O2 TRAVEL
O2:
Hemoglobin
CO2:
Undergoes a reaction and becomes carbonic acid.
Equilibrium shift @ lungs back to CO2.
ROLE OF PRESSURE
CO2: Greater at tissues; movement directed AWAY from tissues.
Oxygen: Greatest in alveoli; movement directed toward tissues
MEASURES
pO2: partial pressure of oxygen at a given atmospheric pressure.
Saturation of O2: amount of oxygen bound to hemoglobin
Concentration of O2: dependent on saturation and pressure.
Normal: >95% saturation
100 mm/mg pO2
20 ml/100mL blood
ROLE OF PRESSURE
Where is the pO2 higher? Lungs or body’s tissues? How does that influence binding to hemoglobin.
Red Arrow:
Blue Arrow:
SUMMARY
THE HIGH ALTITUDE PROBLEM
The concentration of oxygen in air is 20.9%. Pressure at sea level is 760 mmHg.
1) What is the pO2 at sea level?
2) What changes at high altitude?
3) How does that affect physiology?
4) What changes does the body undergo when it spends weeks at high altitude?
WHAT HAPPENS WHEN THE MUSCLES NEED MORE OXYGEN?
Bohr Shift:
Saturation decreased at lower pH.
More O2 falls off blood and enters body tissues.
What do you think the decrease in pH does to hemoglobin to cause this phenomenon?
HOW DOES BLOOD GAS AFFECT BREATHING RATE?
RESPIRATORY SYSTEM CASE STUDY
What happens when a person is afflicted with carbon monoxide poisoning!!!
DISCUSS ANSWERS
This is a practice with multiple choice!!!
What do you need to know to answer the question?!?
Why are wrong answers wrong and why is the right answer right?!?!
CONTROL OF CIRCULATORY SYSTEM
Blood pressure
Heart Rate
BLOOD PRESSURE
WHAT DO THE VALUES TELL US?
REVIEW: ARTERIES AND VEINS
Artery: Away Vein: Towards
REVIEW: HEART/LUNG CIRCULATION
HEART RATE AND PACEMAKER
EKG WITH LETTERS
ABNORMAL HEART RHYTHMS
Describe and Draw each of the abnormal heart rhythms:
Atrial Fibrillation
Tachycardia
Bradycardia
Ventrilcular Fibrillation
Then, write a case study for a patient and have a partner determine which rhythm he/she would likely experience.