4 December 2009 Respiratory Physiology Lab next week: Urinalysis Review website for instructions. Look over Chapter 14 this weekend!

About the Final Exam….. Choice of Tuesday or Wednesday 9-noon Details of format and suggestions are posted to the website. Schedule Change for Spring Biology 484 Human Ecology = Sociology hr Biology Elective Optional 1 hr lab if you want/need a 4 hour Bio course With Dr. Abercrombie

Abstracts Pick up in Milliken 204 this afternoon from 1:30 – 4:30. Anonymously graded Grade average so far is 79 Max = 99 So far, 8 of 50 abstracts in the 90’s How to address an unsatisfactory grade: see which sections most points were lost, and concentrate on improving these sections. Revised abstract due Wednesday Exam Day at 9:00 am. Submit revised abstract, original abstract, original stats report, and 1 st Grading rubric all paper-clipped in this order. Overall abstract grade proportion to be determined.

FlatSteep

At 40 Torr, more DPG, higher temperature, and greater acidity (all indicative of increased metabolism) shift dissociation curve down (Hb has a lower affinity for O 2 ) and thus more O 2 is unloaded into the tissues. Shifting the Oxyhemoglobin dissociation curve Notice the main affect is on the steep portion of the curve which means that there is little influence on the loading of O 2 onto Hb in the lungs

Table 13.09

For negative feedback, 1 What is the stimulus? 2 Where should the receptors be located?

Peripheral Chemoreceptors 1) Carotid bodies (not carotid sinuses which are baroreceptors) 2) Aortic bodies (not aortic arch baroreceptors) Central Chemoreceptors in medulla To ponder: Why should there be three sets of chemoreceptors?

Carbon Dioxide reacts with water! CO 2 + H 2 0 ↔ H 2 CO 3 ↔ H + + HCO 3 - Carbonic Acid Bicarbonate H + can’t cross Blood Brain Barrier but CO 2 does!

Figure 13.36

CO 2 + H 2 0 ↔ H 2 CO 3 ↔ H + + HCO 3 - Carbonic Acid Bicarbonate

Figure 13.34

Figure 13.22

Figure Negative feedback loop for control of blood gases Cervical spinal cord injury

Figure Name the components of the negative feedback loop

Blood gases and pH change very little except when exercise is intense. Therefore, changes in minute ventilation are not the result of negative feeback. How can this be? Respiratory Physiology during Exercise

Experience, learning, modification of motor program, feed forward! Negative feedback operates! But the changes in ventilation at the onset and offset of exercise cannot be explained by negative feedback.

Figure Integrator