Neck - Part 4

Question 1

T4

Answer 1

Thyroxine

Question 2

What is the normal range for thyroxine?

Answer 2

4.5-12ug/dL

Question 3

What does T4 do?

Answer 3

Stimulates consumption of oxygen

Question 4

What is thyroxine secreted by?

Answer 4

Follicular cells of the thyroid

Question 5

What is T4 controlled by?

Answer 5

Thyrotropin

- TSH

Question 6

What amount of iodine needs to be ingested per week for normal thyroxine production?

Answer 6

100-200mg

Question 7

What is decrease of T4 associated with? (2)

Answer 7

1. Thyroid disease

2. Nonfunctioning pituitary gland

Question 8

T3

Answer 8

Triiodothyronine

Question 9

What is the normal range for triiodothyronine?

Answer 9

70-190ng/dL

Question 10

What does T3 do?

Answer 10

Regulates tissue metabolism

Question 11

What is decreased amounts of triiodothyronine associated with?

Answer 11

Hashimoto thyroiditis

Question 12

What is the normal range for calcitonin?

Answer 12

< 100pg/mL

Question 13

What does calcitonin do?

Answer 13

Lowers calcium and phosphorus concentration in the blood

Question 14

What does calcitonin inhibit?

Answer 14

Bone resorption

Question 15

What is calcitonin secreted by?

Answer 15

Parafollicular cells

- C-cells of the thyroid gland

Question 16

What is elevated amounts of calcitonin associated with?

Answer 16

Medullary thyroid carcinoma

Question 17

What are decrease levels of calcitonin associated with? (2)

Answer 17

1. Surgical removal of the thyroid glands

2. Nonfunctioning thyroid glands

Question 18

PTH

Answer 18

Parathormone

- parathyroid hormone

Question 19

What is the normal range of parathormone?

Answer 19

12-68pg/mL

Question 20

What does PTH do?

Answer 20

Regulates calcium metabolism in conjunction with calcitonin

Question 21

Why is parathormone released in response to?

Answer 21

To low extracellular concentration of free calcium

Question 22

What is elevation of PTH associated with?

Answer 22

Hyperparathyroidism

Question 23

What is the normal range of calcium?

Answer 23

8.5-10.5mg/dL

Question 24

What does calcium aid in?

Answer 24

The transportation of nutrients through the cell membranes

Question 25

What is elevation of calcium associated with? (3)

Answer 25

1. hyperparathyroidism 2. Hyperthyroidism 3. Malignancy

Question 26

What levels of calcium is considered life threatening?

Answer 26

14.5mg/dL

Question 27

What are decrease levels of calcium associated with? (2)

Answer 27

1. Nonfunctioning parathyroid glands | 2. Surgical removal of the parathyroid glands

Question 28

Hyperthyroidism

Answer 28

Hyperactivity of the thyroid gland

Question 29

What are the symptoms of hyperthyroidism? (9)

Answer 29

1. Nervousness 2. Exophthalmos 3. Tremors 4. Constant hunger 5. Weight loss 6. Heat intolerance 7. Palpitations 8. Increased heart rate 9. Diarrhea

Question 30

What are the causes of hyperthyroidism? (3)

Answer 30

1. Toxic adenoma 2. Graves disease 3. Trophoblastic tumours

Question 31

What can happen if hyperthyroidism goes untreated?

Answer 31

May lead to cardiac failure

Question 32

What is the percentage of thyroid nodules that are benign?

Answer 32

60%

Question 33

What is the percentage of thyroid nodules that are cysts?

Answer 33

20%

Question 34

What is the percentage of thyroid nodules that are malignant?

Answer 34

20%