ENDOCRINOLOGY

Question 1

What is endocrinology?

Answer 1

The study of the biosynthesis, storage, chemistry, and physiological function of hormones in the endocrine glands and tissues that secrete them.

Question 2

What are hormones?

Answer 2

Circulating messengers that act at a distance from the organ (gland) of origin.

Question 3

Name the 3 classes of hormones.

Answer 3

Steroids, Amines, Proteins/Polypeptides.

Question 4

Give examples of steroid hormones.

Answer 4

Cortisol, testosterone, oestrogen, vitamin D (secreted by adrenal cortex, gonads, kidneys).

Question 5

Give examples of amine hormones.

Answer 5

Epinephrine (adrenal medulla), T3 and T4 (thyroid).

Question 6

Give examples of peptide/polypeptide hormones.

Answer 6

Pituitary hormones, pancreatic islet cell hormones, parathyroid hormones, angiotensin II, atrial natriuretic hormone, hypothalamic releasing hormones, insulin-like growth factor-1.

Question 7

List 5 key functions of the endocrine system.

Answer 7

1. Regulation of growth (in utero & postnatal)
2. Pubertal development & reproduction
3. Energy production
4. Blood pressure regulation
5. Behavior

Question 8

Where is the thyroid gland located?

Answer 8

It consists of bilateral lobes extending from the side of the thyroid cartilage downwards to the 6th tracheal ring, with the isthmus overlying the 2nd & 3rd tracheal rings.

Question 9

What is the embryological origin of the thyroid gland?

Answer 9

It develops from a bud from the floor of the pharynx that descends to its definitive position in the neck.

Question 10

What are the two primary functions of the thyroid gland?

Answer 10

1. Secretion of thyroid hormones (T3 & T4). 2. Secretion of calcitonin (regulates calcium levels).

Question 11

How is thyroid hormone secretion regulated?

Answer 11

By the hypothalamic–pituitary axis. TRH (hypothalamus) stimulates TSH (pituitary), which stimulates thyroid growth, iodine uptake, and release of T3 & T4.

Question 12

What feedback mechanism regulates thyroid hormone levels?

Answer 12

Negative feedback by circulating thyroid hormones on TSH and TRH.

Question 13

Which thyroid hormone is more potent?

Answer 13

T3 is 3–4 times more potent than T4.

Question 14

What element is absolutely required for thyroid hormone synthesis?

Answer 14

Iodine.

Question 15

List 3 functions of thyroid hormones.

Answer 15

• CNS: brain maturation & nerve function. • Growth: skeletal growth & epiphyseal maturation. • Metabolism: ↑ BMR, ↑ heat production, regulates carbohydrate, protein & fat metabolism.

Question 16

What is endocrinology?

Answer 16

The study of the biosynthesis, storage, chemistry, and physiological function of hormones in endocrine glands and tissues that secrete them.

Question 17

What are hormones?

Answer 17

Circulating messengers with action at a distance from the gland of origin.

Question 18

What are the three classes of hormones?

Answer 18

Steroids, Amines, and Proteins/Polypeptides.

Question 19

Which glands primarily secrete steroid hormones?

Answer 19

Adrenal cortex, gonads, kidneys.

Question 20

Give examples of steroid hormones.

Answer 20

Cortisol, testosterone, oestrogen, vitamin D.

Question 21

Which glands secrete amine hormones?

Answer 21

Adrenal medulla and thyroid gland.

Question 22

Give examples of amine hormones.

Answer 22

Epinephrine, T3, T4.

Question 23

Which glands secrete peptide/polypeptide hormones?

Answer 23

Anterior pituitary, posterior pituitary, pancreatic islets, parathyroids, lungs, heart, brain, hypothalamus.

Question 24

Give examples of peptide/polypeptide hormones.

Answer 24

Angiotensin II, atrial and brain natriuretic hormones, hypothalamic releasing hormones, insulin-like growth factor-1.

Question 25

What is the role of the endocrine system in growth?

Answer 25

It regulates growth in utero and postnatally.

Question 26

How does the endocrine system affect reproduction?

Answer 26

It regulates pubertal development and reproduction.

Question 27

How does the endocrine system affect energy?

Answer 27

It regulates energy production.

Question 28

How does the endocrine system affect blood pressure?

Answer 28

It regulates blood pressure.

Question 29

How does the endocrine system affect behavior?

Answer 29

It influences behavior.