Thyroid & Pancreas

Question 1

What hormone does the thyroid release to regulate calcium?

Answer 1

Calcitonin.

Question 2

What is the function of calcitonin?

Answer 2

Regulates calcium levels.

Question 3

Where is parathyroid hormone (PTH) produced?

Answer 3

In the four parathyroid glands behind the thyroid.

Question 4

What is the function of parathyroid hormone (PTH)?

Answer 4

Regulates calcium levels.

Question 5

What is the relationship between estrogens and parathyroid hormone?

Answer 5

Estrogens antagonize PTH and help minimize bone calcium loss.

Question 6

What are the two main thyroid hormones?

Answer 6

Thyroxine (T4) and Triiodothyronine (T3).

Question 7

What are four functions of thyroid hormones?

Answer 7

Energy balance, temperature regulation, increased protein synthesis, increased carbohydrate burning.

Question 8

What cells synthesize thyroid hormones?

Answer 8

Thyroid follicle cells.

Question 9

What dietary element is essential for thyroid hormone synthesis?

Answer 9

Iodine.

Question 10

Which thyroid hormone is active and has higher receptor affinity?

Answer 10

T3 (Triiodothyronine).

Question 10

What protein combines with iodine to form thyroid hormone precursors?

Answer 10

Thyroglobulin.

Question 11

Which thyroid hormone is a pro-hormone and more abundant?

Answer 11

T4 (Thyroxine).

Question 12

What is the effect of salicylates on thyroid hormone activity?

Answer 12

Displace T3 and T4 from TBG → increased hormone activity.

Question 13

What converts T4 into T3?

Answer 13

Peripheral tissues (via de-iodination).

Question 14

What protein carries thyroid hormones in the blood?

Answer 14

Thyroxine-binding globulin (TBG).

Question 15

How do corticosteroids affect thyroid hormone availability?

Answer 15

Decrease TBG levels → reduced hormone availability.

Question 16

What hormone from the hypothalamus stimulates TSH release?

Answer 16

TRH (Thyrotropin-Releasing Hormone).

Question 16

What hormone inhibits thyroid hormone release?

Answer 16

SST (Somatostatin).

Question 17

What hormone from the pituitary stimulates the thyroid?

Answer 17

TSH (Thyroid-Stimulating Hormone).

Question 18

What happens when TSH is chronically elevated?

Answer 18

Goiter formation.

Question 19

How is thyroid hormone production regulated?

Answer 19

Negative feedback loop.

Question 20

What does T3 bind to in target cells?

Answer 20

Thyroid hormone receptors (THRs) in the nucleus.

Question 21

What happens after T3 binds to THRs?

Answer 21

Regulates gene transcription via thyroid hormone response elements (TREs).

Question 22

What type of dimers can THRs form?

Answer 22

With RXR (Retinoid X Receptor).

Question 23

What are general symptoms of hypothyroidism?

Answer 23

Decreased metabolism, fatigue, cold intolerance, weight gain, thin hair, dry skin, goiter.

Question 24

What is a key CNS concern in hypothyroidism?

Answer 24

Increased sensitivity to CNS depressants (e.g., opioids, sedatives).

Question 25

Name three causes of hypothyroidism.

Answer 25

Iodine deficiency, autoimmune disease, thyroid removal.

Question 26

What are oral effects of congenital hypothyroidism?

Answer 26

Delayed tooth eruption, malocclusion, increased periodontal disease.

Question 27

What are oral effects of untreated hypothyroidism?

Answer 27

Poorly shaped, carious teeth.

Question 28

What are symptoms of hyperthyroidism?

Answer 28

Increased metabolism, insomnia, anxiety, heat intolerance, rapid heartbeat, weight loss, osteoporosis, goiter.

Question 29

What is the treatment for hypothyroidism?

Answer 29

Levothyroxine (Synthroid).

Question 30

What are oral effects of hyperthyroidism?

Answer 30

Increased caries, periodontal disease, osteoporosis, accelerated eruption, burning mouth.

Question 31

What is Grave’s disease?

Answer 31

An autoimmune cause of hyperthyroidism.

Question 32

What are oral signs of Grave’s disease?

Answer 32

Gingival pain, excessive salivation, salivary gland inflammation.

Question 33

What is thyrotoxicosis?

Answer 33

Excess thyroid hormone in circulation.

Question 34

What are oral effects of thyrotoxicosis?

Answer 34

Accelerated eruption, jawbone demineralization, periodontal destruction.

Question 35

What is thyroid storm (crisis)?

Answer 35

A life-threatening, stress-induced hyperthyroid emergency.

Question 36

What are symptoms of thyroid storm?

Answer 36

Fever, tachycardia, hypotension, vomiting, diarrhea, delirium.

Question 37

What are treatments for hyperthyroidism or thyroid storm?

Answer 37

Thioamides (e.g., propylthiouracil), radioactive iodine (131I), surgical removal (may require hormone replacement).

Question 38

Where is glucagon produced?

Answer 38

Alpha cells of the pancreas.

Question 39

When is glucagon secreted?

Answer 39

In response to low blood glucose.

Question 40

What is the primary action of glucagon?

Answer 40

Stimulates gluconeogenesis (glucose production).

Question 41

What inhibits glucagon secretion?

Answer 41

High blood glucose levels.

Question 42

Where is insulin produced?

Answer 42

Beta cells of the pancreas.

Question 43

When is insulin secreted?

Answer 43

In response to high blood glucose.

Question 44

What does insulin do to glucose uptake?

Answer 44

Increases glucose uptake by cells.

Question 45

What does insulin promote in terms of glucose storage?

Answer 45

Promotes storage of glucose as glycogen.

Question 46

Through which transporter does glucose enter beta cells?

Answer 46

GLUT2.

Question 47

What does glucose metabolism in beta cells increase?

Answer 47

ATP levels.

Question 48

What does increased ATP do to potassium channels?

Answer 48

Closes ATP-sensitive potassium channels.

Question 49

What does potassium channel closure cause?

Answer 49

Cell membrane depolarization.

Question 50

What does depolarization open in beta cells?

Answer 50

Voltage-gated calcium channels.

Question 51

What triggers insulin release in beta cells?

Answer 51

Calcium influx.

Question 52

From what precursor is insulin cleaved?

Answer 52

Preproinsulin.

Question 53

What peptide is co-released with insulin and used to measure insulin production?

Answer 53

C-peptide.

Question 54

What triggers GLUT4 to move to the cell membrane?

Answer 54

Insulin binding to its receptor.

Question 55

What happens when GLUT4 moves to the membrane?

Answer 55

It enables glucose entry into the cell.

Question 56

What happens to GLUT4 in the absence of insulin?

Answer 56

It remains in cytoplasmic vesicles; no glucose entry occurs.