PHYSIOEX (BIO 101) LAB REPORT ON THYRIOD
HARMONE EFFECT
Exercise 4: Endocrine System
Physiology Activity 1: Metabolism and
Thyroid Hormone Name: Maycee
Smith
Date: 2026-27
Pre-lab Quiz Results
You scored 100% by answering 6 out of 6 questions correctly.
1 Which of the following statements about metabolism is false?
You correctly answered: All of the energy from metabolism is ultimately
stored in the chemical bonds of ATP.
2 Thyroxine is
You correctly answered: the most important hormone for maintaining the
metabolic rate and body temperature.
3 Thyroid-stimulating hormone (TSH) is
You correctly answered: produced in the pituitary gland.
4 An injection of TSH to an otherwise normal animal will cause which of the
following?
You correctly answered: goiter development.
5 Thyrotropin-releasing hormone (TRH) is
You correctly answered: secreted by the hypothalamus.
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6 Which of the following statements is true?
You correctly answered: The hypothalamus primarily secretes tropic
hormones that stimulate the secretion of other hormones.
Experiment Results
Predict Questions
1 Predict Question 1: Make a prediction about the basal metabolic rate
(BMR) of the remaining rats compared with the BMR of the normal rat you
just measured.
Your answer: The BMR of both remaining rats will be lower than the normal
rat's BMR. i
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2 Predict Question 2: What do you think will happen after you inject
thyroxine into the three rats?
Your answer: The normal rat will become hyperthyroidic and develop a
goiter.
3 Predict Question 3: What do you think will happen after you inject TSH into
the three rats?
Your answer: The normal rat will become hyperthyroidic and develop a
goiter.
4 Predict Question 4: Propylthiouracil (PTU) is a drug that inhibits the
production of thyroxine by blocking the attachment of iodine to tyrosine
residues in the follicle cells of the thyroid gland (iodinated tyrosines are
linked together to form thyroxine). What do you think will happen after
you inject PTU into the three rats?
Your answer: The thyroidectomized rat will become hypothyroidic and
develop a goiter.
Stop & Think Questions
1 Calculate the oxygen consumption per hour for this rat using the
following equation. ml O2 consumed/1 minute x 60 minutes/hour =
ml O2/hour
Enter the oxygen consumption per
hour. You answered: 432 ml O2/hr.
2 Now that you have calculated the oxygen consumption per hour for
this rat, you can calculate the metabolic rate per kilogram of body weight
with the following equation (note that you need to convert the weight
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