Introduction to endocrine system Flashcards Preview

PM3B: Autumn > Introduction to endocrine system > Flashcards

Flashcards in Introduction to endocrine system Deck (14):
1

What are the two major control systems of the vertebrate body

Endocrine System

Nervous System

2

What does the endocrine system regulate

Growth
Development
Reproduction
Senescene

3

What is the definition of a hormone

A chemical messenger produced and secreted by a specialised endocrine gland that is transported in the blood stream to a distant target organ/cell where it elicits a physiological response

4

Give examples of endocrine systems

Hypothalamus
Posterior and anterior pituitary
Thyroid
Heart
Liver
Stomach and small intestine
Pancreas
Kidney
Skin

5

What are the three classes of hormone and give an example for each

1. Proteins and peptides:
Growth hormone

2. Cholesterol derivatives:
Steroids
Vitamin D
Steroid hormones: glucocorticoids, aldosterone

3. Modified Amino acids:
Structure changes to become amino acid
Adrenaline- hydrophilic
THYROID hormones- hydrophobic

6

What does hormone action affect

growth
Development
Metabolic activity
Tissue function

7

What are circulating hormones influenced by

Rate of secretion

Rate of metabolism

Serum binding proteins

8

How is hormone secretion regulated by physiological changes in blood glucose, stress and blood calcium

Blood glucose- regulates insulin and glucagon release from pancreas

Stress: adrenaline release from adrenal medulla

Blood calcium: regulates parathyroid hormone from parathyroids

9

How is hormone secretion regulated by endogenous rhythms like ultradian, circadian, infradian

Ultradian- cycles every so minutes (GnRH pulses)

Circadian- daily cycles (testosterone and cortisol every 24 hours)

Infradian- monthly cycles (LH in females- 28 day period)

10

What is a negative and positive feedback loop

Negative- maintains homeostasis via a loop to the gland the hormone came from

Positive- stimulates more hormone production
Example: Pre-ovulatory LH surge

11

What is ectopic hormone secretion and give an example

Hormone made outside of normal endocrine gland such as a tumour

12

What is addisons disease

Destruction of adrenal cortex

13

What can a lack of in diet cause hyposecretion

Lack of Iodine deficiency

14

What is Laron syndrome

GH receptor mutation that leads to raised/normal Growth hormone levels