ACTIVITY 1: Metabolism and Thyroid Hormone

Part 1:

Chart 1: Effects of Hormones on Metabolic Rate | | Normal Rat | Thyroidectomized Rat | Hypophysectomized Rat | BaselineWeightMl O2 used in 1 minuteMl O2 used per hourMetabolic ratePalpation results | 250.9 grams 7.1 ml 426 ml 1697 ml O2/kg/hr | 245.7 grams 6.2 ml 372 ml 1514 ml O2/kg/hr | 244.6 grams 6.1 ml 366 ml 1496 ml O2/kg/hr | With thyroxineWeightMl O2 used in 1 minuteMl O2 used per hourMetabolic ratePalpation results | 249.5 grams 7.9 ml474 ml1899 ml O2/kg/hr | 245.9 grams 7.5 ml450 ml 1830 ml O2/kg/hr | 244.6 grams 7.5 ml 450 ml 1839 ml O2/kg/hr | With TSHWeightMl O2 used in 1 minuteMl O2 used per hourMetabolic ratePalpation results | 249. 8 grams 7.8 ml468 ml1873 ml O2/kg/hr | 245.7 grams 6.2 ml 372 ml 1514 ml O2/kg/hr | 245.2 grams 7.4 ml 444 ml 1810 ml O2/kg/hr | With propylthiouracil WeightMl O2 used in 1 minuteMl O2 used per hourMetabolic ratePalpation results | 250.8 grams 6.2 ml 372 ml 1483 ml O2/kg/hr | 244.0 grams 6.1 ml 366 ml 1500 ml O2/kg/hr | 244.6 grams 6.0 ml 360 ml 1471 ml O2/kg/hr |

1) Which rat had the fastest baseline metabolic rate?

Normal Rat

2) Why did the metabolic rates differ between the normal rat and the surgically altered rats? How well did the results compare with your prediction?

They differed because the other two rats are missing the thyroid-stimulating