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Lab #10 part B In order for chemical reactions to occur:

Lab #10 part B In order for chemical reactions to occur:. Molecules must collide - They collide w/ a certain impact. In order for chemical reactions to occur:. The greater their kinetic energy… The greater their force of collision.

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Lab #10 part B In order for chemical reactions to occur:

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  1. Lab #10 part BIn order for chemical reactions to occur: • Molecules must collide - • They collide w/ a certain impact

  2. In order for chemical reactions to occur: • The greater their kinetic energy… • The greater their force of collision

  3. The greater the kinetic energy… the greater the force of collision

  4. TEMPERATURE IS A MEASURE OF KINETIC ENERGY!

  5. leads to an increase in collisions… Increase in temperature …

  6. Living organisms need the proper temperature for proper amount of collisions

  7. Living organisms have a temp. dilemma: • Must have increased temperature for proper molecular collisions

  8. Temperatures too high (about 40oC or higher) • May denature proteins and ultimately kill an individual

  9. Evolution has solved this problem: • 1) Enzymes

  10. Evolution has solved this problem: • 2) Behavioral, morphological and physiological traits designed to maintain a warm body…

  11. Ectotherm vs. Endotherm Rapid Metabolism produces much heat… Metabolism is soooooo slow, their bodies produce little heat… every animal besides a bird or mammal

  12. How does a terrestrial ectotherm thermo regulate?

  13. How does a terrestrial ectotherm thermo regulate?

  14. What is the ADVANTAGES of ectothermy??? require very little energy… b/c their metabolism is soooo slow. do not have enough energy for sustained exertion. do not have to eat as often.

  15. How does a terrestrial endotherm thermo regulate? Insulating fat, feathers, or fur Maximize blood flow

  16. What is the ADVANTAGES of endothermy??? elevated, constant body temperature, despite changes in environment maximize metabolic rate. can live in colder climates... HOWEVER, must have a constant food supply!!

  17. How does an aquatic ectotherm thermoregulate?

  18. Their metabolism speeds up or slows down?

  19. Circulationquick review • Water flows over gills as fish swims • Gills are made of thousands of gill filaments • Fish, open their mouths, and H2O flows over the gills

  20. Circulationquick review • Deoxygenated blood flows into the gills • Oxygen flows from the water into the gills and is picked up by the blood. • It goes to the rest of the body.

  21. Oxygen-poorblood Gill arch Oxygen-richblood Lamella Blood vessel Gill arch 15% 40% 5% Water flow 70% 30% Operculum 100% 60% 90% Blood flowthrough capillariesin lamellaeshowing % O2 O2 Water flowover lamellaeshowing % O2 Gillfilaments Figure 42.21 Countercurrent exchange The effectiveness of gas exchange in some gills, including those of fishesIs increased by ventilation and countercurrent flow of blood and water

  22. Figure 42.1 Form fits Function

  23. On with the Lab…

  24. The lab examines the relationship between metabolic rate & body temp. in ectotherms

  25. We will measure the heart rate (indirectly) to measure metabolism • The rate of metabolism in ectothermic animals increases as the environmental temperature increases • This rise occurs because the reactants in the cell have greater thermal energy, and many cellular enzymes are more active as temperature increases.

  26. What is the effect on a 10oC rise in temperature? • The relationship between temperature changes & metabolic rate is often measured as Q10. • If the metabolic rate doubles with a 10°C increase in temperature, then Q10 = 2.

  27. What is the effect on a 10oC rise in temperature? • Simply choose two points on the graph that are 10 degrees apart, • Determine their respective rates, • and find their quotient.

  28. What is the effect on a 10oC rise in temperature? • The usefulness of calculating a Q10 value is that it suggests whether or not the metabolic reactions being examined are controlled by temperature or by some other factor. IF Q10 IS NOT 2 (aprx.) SOMETHING BESIDES TEMP. IS AFFECTING THE RATE!

  29. If the Q10 = 3… then for every 10oC increase in temp / metabolic rate would TRIPLE • Q10 measures the increase in metabolic activity resulting from an increase in body temperature.

  30. You can measure Q10 indirectly, by measuring heart rate beats min.

  31. (higher temp.) Rate at temperature “X” + 10oC Q10 = Rate at temperature “X” (lower temp)

  32. Q10 is the ratio of the rate of a reaction at one temperature divided by the rate of the same reaction at a temperature 10 C° less. The larger the Q10 the greater the effect the temperature has on the reaction. A value of Q10 = 1 implies temperature has no effect on the reaction.

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