Endocrine Flashcards
Name the endocrine glands/organs
Pineal gland
Hypothalamus
Pituitary gland
Thyroid
Adrenal glands
Pancreas
Ovaries/ Testes
Which hormone reduces blood sugar?
Insulin
Which hormone increases blood sugar
Glucagon
“Glucose-is-gone”
Which pancreatic cells produce insulin?
Beta cells
(Within islets of langerhans)
Which pancreatic cells produce glucagon?
Alpha cells
(Within islets of langerhans)
How does insulin lower blood-glucose levels?
Interacts with cell membranes to open glut-4 channels, increasing cellular uptake of glucose
Inhibits gluconeogenesis
Increases glycolysis
Glucose storage as fat
What is the role of the endocrine system?
Maintain homeostasis
Control storage and utilisation of energy
Regulation of growth, development and reproduction
Respond to environmental stimuli
What are hormones?
Chemical messengers secreted into the blood. They act only where there is a receptor
What can hormones do?
Change membrane permeability or membrane potential
Activate or inhibit enzymes
Stimulate or inhibit mitosis
Stimulate or inhibit secretion
Turn on/off gene transcription
What two gonadotropin hormones are produced by the anterior pituitary
Follicle Stimulating Hormone (FSH)
Luteinising Hormone (LH)
Name a hormone produced by the thyroid
Thyroxin
Triiodothyronine
Describe the role of the thyroid in calcium homeostasis
Rising Ca2+ triggers the thyroid to release calcitonin, this stimulates calcium to deposit in bone.
Falling Ca2+ detected, parathyroid releases parathyroid hormone (PTH). PTH stimulates osteoclasts to degrade bone, increasing blood Ca2+
What is produced in the adrenal glands?
Aldosterone (by zona glomerulosa)
Corticosteroids (by zona fasciculata)
Adrenaline and noradrenaline (by adrenal medulla)
Androgens
Name two opposing pituitary disorders
Gigantism (hypersecretion of GH)
Dwarfism (hyposecretion of GH)
What is Cushings Syndrome?
Excess free cortisol production
Symptoms of Cushing’s syndrome
Abnormal fat deposits- “buffalo hump”, moon face, female balding, hypertension, hyperglycaemia, etc