DBQ: Factors Affecting Muscle Growth (p. 266)
1) Looking at figure a, it is evident that the body mass of the Sturnus vulgaris increased between 2 weeks-4 weeks for the control group 2 by at least 4g. In contrast, the exercise group showed no change in body mass for 4 weeks. Also, after 4 weeks, a greater decline in body mass is evident in the exercise group (with 2g decrease) than the control group 2 (with 1g decrease).
2) In this case, the claim that preventing exercise increases pectoralis muscle mass is supported. In figure b, it is clearly evident that the muscle mass in starlings have shown a larger in crease in the controlled groups 1 and 2, in contrast to the exercise group.
3) The mass of the birds’ pectoralis muscle could be determined by calculating the ratio between the % weight of the pectoralis muscles against the total body mass.
4) The restrictions of motion for animals to gain more muscle mass to be designed and used in the farming of poultry would bring about many ethical concerns. The concerns refer to the animal subjects suffering and effect on their health. Also the pain for not being able to move freely and gaining lots of unnecessary muscle, effecting their physical aspects. Thus, many would think of this experiment as ethically wrong as it concerns them to think of the harm it would put on the animal subjects.