Which rat had the fastest basal metabolic rate (BMR)? ✔✔the normal rat
Why did the BMR's differ between the normal rat and the surgically altered rats? ✔✔The other
2 rats had either had the thyroid or pituitary gland surgically removed. This plays an important
part in hormone secretion to raise or lower BMR.
If an animal had been thyroidectomized, what hormone(s) would be missing in its blood?
✔✔Thyroxine and Calcitonin
If an animal had been hypophysectomized, what effect(s) would you expect to see in the
hormone levels in its blood and in its BMR? ✔✔The metabolic rate would go down with no
pituitary gland to produce THS
What was the effect of thyroxine injections on the normal rat's BMR? ✔✔The metabolic rate
increased to 2000, which was higher than the baseline
What was the effect of thyroxine injections on the thyroidectomized rat's BMR?
How does the BMR in this case compare with the normal rat's BMR?
Was the dose of thyroxine in the syringe too large, too small, or just right? ✔✔The metabolic
rate was increased to 1910 which was not as high as the baseline.
Metabolic rates were raised to reach normal rates, even though still lower than baseline. It has a
pituitary gland so some hormones are still there.
What was the effect of thyroxine injections on the hypophysectomized rat's BMR?
How does the BMR in this case compare with the normal rat's BMR?
Was the dose of thyroxine in the syringe too large, too small, or just right? ✔✔It raised the
metabolic rate but not as high as the thyroidectomized or normal rats. The rat has it's thyroid but
no pituitary gland, it is lowest on the metabolic rate.
What was the effect of TSH injections on the normal rat's BMR? ✔✔The metabolic rate went up
and the baseline was a lot lower.
What was the effect of TSH injections on the thyroidectomized rat's BMR? How does the BMR
in this case compare with the normal rat's BMR? Why did this happen? ✔✔Metabolic rate did
not really go up, just a little above baseline. Without a thyroid to stimulate, TSH not very
effective
What was the effect of TSH injections on the hypophysectomized rat's BMR?