Question: The Data For This Exercise Were Compiled From Seven Sets Of Laboratory Rats (Rattus Norvegicus). Only Male Rats Were Used In Order To Simplify The Study Of The Relationship Between The Reproductive And Endocrine Systems. One Set Of Rats Served As The Control Group, While The Remaining Six Sets Of Rats Constituted The Experimental Groups. In Each Set …

The data for this exercise were compiled from seven sets of laboratory rats (Rattus norvegicus). Only male rats were used in order to simplify the study of the relationship between the reproductive and endocrine systems. One set of rats served as the control group, while the remaining six sets of rats constituted the experimental groups. In each set of rats, there was one “intact” rat (meaning “unaltered”) and one “castrated” rat. The castration procedure involved surgical removal of the testes (under anesthesia), which served to eliminate testosterone production. All fourteen of the rats in this experiment were treated alike in all other ways (food, water, etc.). All experimental rats were injected with a hormone on a daily basis for 2 weeks. The control rats were injected with normal saline. All of the animals were euthanized after the two-week period. The major endocrine organs were removed from each animal and weighed. The following data (Table 8.1; was thus obtained: Testes (mg) Prostate (mg) 3200 425 387 3000 430 380 5700 800 375 Rat Body Adrenal Pituitary Thyroid Thymus Weight Glands (mg) (mg) (mg) (8) (mg) Control 300 (Intact) 12.9 250 475 40 Control (Castrated) 270 12.9 250 480 40 Unknown 1 (Intact) 200 10.1 245 250 100 Unknown 1 (Castrated) 195 10.1 250 250 95 Unknown 2 (Intact) 385 9.8 250 480 40 Unknown 2 (Castrated) 275 13.0 250 480 42 Unknown 3 (Intact) 490 10.2 252 470 38 Unknown 3 (Castrated) 485 10.1 470 41 Unknown 4 (Intact) 160 25 490 462 39 Unknown 4 (Castrated) 144 25.7 495 460 38 Unknown 5 (Intact) 150 9.8 245 150 30 Unknown 5 (Castrated) 135 9.7 247 140 29 Unknown 6 (Intact) 152 8.0 500 455 37 Unknown 6 (Castrated) 135 7.8 SOS 461 37 Table 8.1 Organ weights from control and experimental loboratory animals, 2400 900 250 800 3150 400 375 3200 410 380 2790 405 375 NOTE: For the defined purposes of this experiment a significant change hos occurred ONLY if the organ weight in the experimental animal is >20% different than that of the matched control. If the change is 20%, it is attributed to either experimental (measurement) errors or individual differences among rots. Part 1: Based upon the data provided in Table 8.1 (and the information in the hormone effects table which you completed) identify the hormone that you believe was injected into each set of rats and then explain how you arrived at that conclusion. (Be sure to indicate which specific data most strongly influenced your decision.] UNKNOWN HORMONE EXPLAIN YOUR REASONING 2 3 5 6 COMPREHENSION QUESTIONS 1. Describe how it is possible for the presence of a hormone to lead to the increase in the size of a gland, even when there are no receptors for that specific hormone located on that gland.fi.e. describe how indirect effects of hormones are normally produced) 2. What is negative feedback? How does a negative feedback loop regulate hormone release? Which of the unknown hormones here showed a negative feedback effect? How do we know this? 3. Fill in the following table that Lutline the three complete endocrine negative feedback systems: hypothalamic anterior pituitary terminal endocrine final endocrine hormones) hormone gland product testis T3 and T ACTH 4. Define hypertrophy. Explain what kind of cellular changes a hormone would have to make to cause hypertrophy of its target tissue/organ. 5. Explain the purpose of injecting saline into the control rats in this experiment.