Thyroid Gland

Question 1

What controls the normal secretion of the thyroid gland (which in turn controls metabolism)?

Answer 1

The hypothalamus and the pituitary gland

Question 2

What two groups of hormones does the thyroid gland produce?

Answer 2

Thyroid hormones (amine)
and
Calcitonin (peptide)

Question 3

What does thyroid hormones (amines) do?

Answer 3

increase metabolic rate & body heat production

Question 4

What are the two types of thyroid hormone?

Answer 4

Thyroxine (T4)
and
Triiodothyronine (T3)

Question 5

What does Calcitonin do?

Answer 5

Increases bone matrix formation & Ca2+ secretion form kidneys. Also reduces blood Ca2+ levels

Question 6

What mechanism is tyrosine regulation?

Answer 6

Negative feedback on anterior pituitary gland to decrease TSH

Question 7

Give a example of a metabolic process that thyroxine controls?

Answer 7

thermogenesis

Question 8

What are the 5 functions of T3 and T4?

Answer 8

1. increase protein and enzyme synthesis
2. Increase size and number of mitochondria un cells
3. Promote rapid cellular uptake of glucose
4. Enhance glycolysis and glycogenesis
5. Increase FFA availability for oxidation

Question 9

What is the function of Calcitonin?

Answer 9

Metabolizes calcium

Question 10

How are thyroid diseases diagnosed?

Answer 10

Neck ultrasound

Thyroid scan using radioactive iodine or Tc99

Question 11

What are the hormone levels for primary hyperthyroidism?

Answer 11

T3/T4 levels increased

TSH levels decreased

Question 12

What are the hormone levels for secondary hyperthyroidism?

Answer 12

T3/T4 levels increased

TSH levels increased

Question 13

What causes the problem in primary hyperthyroidism?

Answer 13

The thyroid gland

Question 14

What causes the problem in secondary hyperthyroidism?

Answer 14

The pituitary gland

Question 15

What is Graves disease caused by?

Answer 15

A overproduction of thyroid hormone

Question 16

Name three symptoms of Graves disease

Answer 16

exophthalmos (bulging eyes)
decreased body weight
increased heart rate

Question 17

What is produced during Graves disease?

Answer 17

Production of thyroid stimulating immunoglobulin which mimics TSH (no negative feedback)

Question 18

What is the aetiology (cause of) hyperthyroidism?

Answer 18

Autoimmune
Graves disease
Adenocarcinoma

Question 19

What is the target gender and age range for hyperthyroidism?

Answer 19

Females > Males

Mean age: 20-40 years

Question 20

Name three drugs that affect thyroid function

Answer 20

Glucocorticoids
Amiodarone
Colestipol

Question 21

What causes simple diffuse goiter?

Answer 21

Stimulation of the gland by TSH in response to low levels of thyroid hormone

Question 22

What are the three antithyroid drugs for hyperthroidism?

Answer 22

Carbimazole
Propylthiouracil
Synthesis inhibitors

Question 23

What symptomatic relief of hyperthyroidism?

Answer 23

Propranolol
Beta-blocker
Decrease SNS activity
No smoking

Question 24

What are palliative treatments for hyperthyroidism?

Answer 24

Diet 
Calorie intake
Increase fluids
Decrease Na
Decrease fibre
Decrease caffeine

Question 25

What are some symptoms of hypothyroidism?

Answer 25

Weight gain Decreased alertness Decreased body temperature Goitier formation

Question 26

Why is there reduced thyroid hormone production during hypothyroidism?

Answer 26

Due to iodine deficiency

Question 27

What are the causes of primary hypothyroidism?

Answer 27

Autoimmune hypothyroidism- Hashimoto's thyroiditis Iodine deficiency Congenital defects

Question 28

What is the causes of secondary hypothyroidism?

Answer 28

Isolated TSH deficiency Hypopituitarism hypothalamic disorders

Question 29

What are three signs of hypothyroidism in the elderly?

Answer 29

Tiredness Dry skin Slowing intellectual activity e.g. poor memory and difficulty concentrating

Question 30

What is iodine essential for?

Answer 30

Its central to the molecular structure and manufacture of thyroid hormones

Question 31

What are three signs of cretinism?

Answer 31

Stunted growth Infantile appearance-Puffy face protuberant abdomen Neurological defects

Question 32

What is creationism caused by?

Answer 32

Iodine deficiency in early life

Question 33

What are drug treatments for hypothyroidism?

Answer 33

Levothyroxine Sodium | Liothyronine Sodium

Question 34

How many lobes does the thyroid gland consist of?

Answer 34

2 lobes lying over the larynx

Question 35

What are T3 and T4 attached to in the blood?

Answer 35

Binding globulins

Question 36

Which thyroid hormone is active?

Answer 36

T3 (T4 converted to T3 in the liver)