Hashimoto's disease is an autoimmune disordee that decreases the ability of the thyroid gland to produce t3 and t4. the student is modeling the reaction to increased tsh levels in an individual with untreated hashimoto's disease compares to an individual without hashimoto's disease. which of the following should be used as an independent variable?
tsh level
trh level
t3 level
t4 level

TSH level, because if we are testing the levels of TSH with a person who has Hashimoto's disease and one who does not have Hashimoto's disease.

enzyme active site and substrate specificity

enzymes bind with chemical reactants called substrates. there may be one or more substrates for each type of enzyme, depending on the particular chemical reaction. in some reactions, a single-reactant substrate is broken down into multiple products