Why did the normal rat develop a palpable goiter with the TSH injection? The TSH receptors on the thyroid gland were excessively stimulated. ... because the surgically altered rats do have have a functioning thyroid gland.

Which of the rats did not develop a goiter?

The normal rat will become hyperthyroidic but will not develop a goiter. What do you think will happen after you inject TSH into the three rats? The normal rat will become hyperthyroidic and develop a goiter.

Which rat had the fastest metabolic rate?

• normal rat had the fastest basal metabolic rate because it was ot missing its pituitary gland or its thyroid gland. ...
• normal rat has highest bmr because it has glands required to stimulate and regulate the release of the thyroid hormones.

Did the thyroxine injection produce goiter in any of the rats?

The hormones would be low, because the pituitary gland is important to stimulate the thyroid to secrete thyroxine. What was the effect of thyroxine injections on the normal rat's BMR? The normal rat became hyperthyroidic but it did not develop a goiter.

Why were ovariectomized rats used in this experiment How does the fact that the rats are ovariectomized explain their baseline T scores?

How does the fact that the rats are ovariectomized explain their baseline T scores? They were used since they no longer produce estrogen and this experiement tested estrogen therapy or calcitonin therapy. The rats all had osteoporosis since estrogen loss weakens bone growth, which is why they had baseline T scores.

What are some of the risks of having a goiter?

What hormones will be missing in the rat that was Hypophysectomized?

If an animal has been hypophysectomized, what effect would you expect to see in the hormone levels in its body? TSH levels will be missing because the pituitary gland is removed, so decreased metabolic rate. What was the effect of throxine injections on normal rats BMR?

What is the BMR of the normal rat?

The BMR of normal rats age 3-32 weeks showed a curvilinear correlation with body weight (BWt), BMR = 1.24 BWt0. 583; organ weight (OWt), BMR = 4.30 OWt0. 766; and organ protein (OPr), BMR = 4.30 OPr0. 604.

Why did the rat develop a palpable goiter?

Why did this rat develop a palpable goiter? The effect of PTU injections on the normal rat was to decrease the BMR. The palpable goiter was due to the buildup of the precursors to thyroxine. ... The effect of PTU injections on the thyroidectomized rat was not visible because there was no thyroid gland to be affected.

Why did this rat develop a goiter?

The administration of propylthiouracil (PTU) injection into the normal rat resulted in the decrease on the basal metabolic rate (BMR). The palpable goiter was developed because of the accumulations of antecedents to thyroxine.

Why didn't the administration of TSH have any effect on the metabolic rate of the Thyroidectomized rat?

Referring to Activity 1, why didn't the administration of thyroid-stimulating hormone (TSH) have any effect on the metabolic rate of the thyroidectomized (Tx) rat? The Tx rat lacked a thyroid gland so the TSH had nothing to act on. ... Thyroxine increased the baseline metabolic rate in each rat.

What did the thyroxine injection do to the rats?

Thyroxine injection decreased body weight gain in both growth stages. Bone length, width and weight were not affected by thyroxine injection in weaned rats. Thyroxine injection increased femur length and tail growth, but did not change bone width in suckling rats.

What hormone stimulates the breakdown of polymerized glucose?

Glucagon is released by the pancreas in response to low blood glucose levels and stimulates the breakdown of glycogen into glucose, which can be used by the body. The body's basal metabolic rate is controlled by the thyroid hormones thyroxine (T₄) and triiodothyronine (T₃).

Which gland secretes the hormone that controls metabolism?

The thyroid gland and parathyroid glands are located in front of the neck, below the larynx (voice box). The thyroid plays an important role in the body's metabolism.

What is the primary effect of thyroid hormones T3 and T4?

The main activity of the thyroid hormones T3 and T4 is to boost the basal metabolic rates of proteins, fats, and carbohydrates as well as vitamins.

What happens when thyroxine is too low?

Low thyroxine levels cause problems with development if it occurs when an individual is young. In adults, thyroxine deficiency will lower the metabolic rate, causing weight gain, memory problems, infertility, fatigue, and muscle stiffness.

What was the effect of TSH on the normal rats metabolic rate?

TSH injections increased the normal rat's metabolic rate. Why? Because high TSH stimulated more thyroid hormone to be released, which in turn increased the metabolic rate.

What does PTU do to metabolic rate?

There was found to be a significant reduction in liver weight to body weight ratio in the PTU-treated animals, which probably resulted from the lowered metabolic rate since the liver functions in connection with carbohydrate, fat, and protein metabolism.

Which hormone is released from the pituitary gland?

The major hormones produced by the pituitary gland are: ACTH: Adrenocorticotrophic hormone. Stimulates the production of cortisol, a “stress hormone” that maintains blood pressure and blood sugar levels. FSH: Follicle-stimulating hormone.

How does administering PTU affect the body?

The most common side effects are related to the skin and include rash, itching, hives, abnormal hair loss, and skin pigmentation. Other common side effects are swelling, nausea, vomiting, heartburn, loss of taste, joint or muscle aches, numbness and headache, allergic reactions, and hair whitening.

Which patient would most likely be diagnosed with Cushings disease?

Who is more likely to have Cushing's syndrome? Cushing's syndrome most often affects adults, usually aged 30 to 50,¹ but can also occur in children. Cushing's syndrome affects about three times as many women as men.

How did the baseline metabolic rates of the three rats differ?

How did the baseline metabolic rates of the three rats differ? The normal rat's metabolic rate was the lowest. The thyroidectomized rat's metabolic rate was the highest. ... The metabolic rates for the thyroidectomized and hypophysectomized rats were lower than that of the normal rat.

What is a glucose standard curve and why is one needed for this experiment?

What is a glucose standard curve, and why did you need to obtain one for this experiment? Glucose standard curve is a graphic tool to demonstrate the relationship between optical density and glucose concentration. You need it because you don't have too many samples to compare with so you have to extrapolate.

Why did the metabolic rate differ between the normal rat in the surgically altered rats How well did the results compare with your prediction?

How well did the results compare with your prediction? The metabolic rates differed between the normal rat and the surgically altered rats because the surgically altered rats could not produce specific hormones (t4 and TSH) since they no longer have either a thyroid or pituitary gland.

What effect will saline injections have on the control rats vertebral bone density?

The saline injections will not change the rat's vertebral bone density (indicated by an unchanging T score).

When there are high levels of cortisol it will inhibit the release of which hormones?

High levels of stress hormones over a long period can have negative effects on the body. Because of this, cortisol blocks the continued release of corticotrophin-releasing hormone and switches off the hypothalamus–pituitary–adrenal axis, which is known as a negative feedback loop.