Bio Lecture 3 Page 1/21/11 Lecture Pt 4

1. Which two hormones regulate their own level via two negative feedback loops in the endocrine system?

Insulin and Glucagon

Adrenaline and Noradrenaline

Thyroid hormones namely Ts and T4 regulate their own level via two negative feedback loops.
TRH = TSH Releasing HormoneTSH = Thyroid Stimulating Hormone
T3 crosses membrane binds to receptor, and alters gene expresson

Estrogen and Progesterone

Thyroid hormones regulate their own level through two negative feedback loops, where TSH Releasing Hormone (TRH) stimulates the release of Thyroid Stimulating Hormone (TSH), which in turn controls the production of T3 and T4.

Explanation

Thyroid hormones regulate their own level through two negative feedback loops, where TSH Releasing Hormone (TRH) stimulates the release of Thyroid Stimulating Hormone (TSH), which in turn controls the production of T3 and T4.

2. Enlarged thyroid AKA _____r results from breakdown in _______. Is this a result from hyper or hypo thyrodism? Explain why there is a growth below chin.

Enlarged thyroid AKA Cretinism results from congenital absence of thyroid gland.

Enlarged thyroid AKA Nodule results from overproduction of TSH.

Enlarged thyroid AKA Goiter results from breakdown in Negative feedback loop.
Hypothyroidism: When there is insufficient thyroidhormone (for example with an iodine deficiency) there is no hormone availableto feedback and turn off TSH production. The thyroid grows in an effort to meetthe demand.

Enlarged thyroid AKA Thyrotoxicosis results from excessive secretion of thyroid hormones.

In hypothyroidism, the enlarged thyroid, also known as Goiter, is a result of the breakdown in the negative feedback loop due to insufficient thyroid hormone production.

Explanation

In hypothyroidism, the enlarged thyroid, also known as Goiter, is a result of the breakdown in the negative feedback loop due to insufficient thyroid hormone production.

3. Which statement accurately describes Graves Disease?

Graves Disease is a result form Hyperthyrodism.
An autoimmune disease in which antibodies are made bymistake that bind and activate theTSH receptor so that the thyroid does not respond to negative feedback andthyroid hormone continues to be released.

Graves Disease is a result from Autoimmune Disorder.

Graves Disease is a result of Thyroid Surgery.

Graves Disease is a result form Hypothyrodism.

Graves Disease is characterized by hyperthyroidism, not hypothyroidism. It is an autoimmune disease, not a result of thyroid surgery. The correct answer states that it is a result of hyperthyroidism.

Explanation

Graves Disease is characterized by hyperthyroidism, not hypothyroidism. It is an autoimmune disease, not a result of thyroid surgery. The correct answer states that it is a result of hyperthyroidism.

4. The thyroid gland releases thyroid hormone which is actually two molecules, __& __, derived from ____ (amino acid). These hormones regulate ___, ___, and ___. ____ is the most active form and ___ is typically converted to ___ upon arrival in the target cells.

The thyroid gland releases thyroid hormone which isactually two molecules , T3 and T4 , derived from tyrosine. These hormones regulate overall metabolic rate, bloodpressure, and heart rate.T3 is the most activeform and T

T5 and T6, phenylalanine, blood sugar levels, bone density, cellular respiration

T7 and T8, cysteine, immune response, cholesterol levels, lipid synthesis

T1 and T2, tryptophan, body temperature, muscle strength, digestion

The correct answer is T3 and T4 derived from tyrosine, which regulate overall metabolic rate, blood pressure, and heart rate. T3 is the most active form, and T4 is commonly converted to T3 upon reaching the target cells.

Explanation

The correct answer is T3 and T4 derived from tyrosine, which regulate overall metabolic rate, blood pressure, and heart rate. T3 is the most active form, and T4 is commonly converted to T3 upon reaching the target cells.