Module 7 Flashcards
The body can secrete products from two different types of glands. What are they?
Endocrine
Exocrine
Cells of these glands secrete hormones directly into interstitial fluid surrounding secretory cells. The hormones are then picked up by the blood capillaries.
Endocrine
Glands that secrete cell products into a duct system
Exocrine
Endocrine glands secrete molecules called ___________. These act as chemical messengers, travelling through the blood circulation to cause an effect on the target organ
hormones
Name 5 endocrine glands
Pituitary
Thyroid
Parathyroid
Adrenal
Pancreas
What gland is a pea-sized gland that sits at base of brain and extends from the hypothalamus. It is known as the “master gland” as it produces and releases hormones that control all other endocrine glands.
Pituitary
Which gland sits anterior to the trachea and produces thyroid hormones important for metabolism? It is also involved in calcium homeostasis.
Thyroid gland
These glands are four small oval glands situated on the back of the thyroid gland. They are paired, with two superior and inferior. They are involved in the maintenance of calcium homeostasis. What are they?
Parathyroid glands
These are paired and sit on top of each kidney. They have important roles in the production of corticosteroids as well as the maintenance of fluid balance. What are they?
Adrenal/Suprarenal glands
What are corticosteroids?
Group of steroid hormones produced by cortex of adrenal gland responsible for several functions (ex. glucose metabolism, sex characteristics, electrolyte balance of body fluids)
What gland has both endocrine and exocrine functions? It is located posterior to the stomach extending from the duodenum (first part of small intestine) to the spleen. Its main endocrine function is to control sugar levels in the blood.
Pancreas
How big is the pituitary gland? Where is it located/extend from? Where does it sit?
Pea size
Extends from hypothalamus
Located inferior to hypothalamus
Sits in concavity of sphenoid bone in middle of skull
What is known as the “master gland” why?
Pituitary gland
Produces and releases hormones that control all other endocrine glands
Where is the thyroid gland located?
Anterior to trachea; inferior to larynx
What are the functions of the thyroid glands? (2)
Produces thyroid hormones, important for metabolism
Involved in calcium homeostasis
How many small oval glands make up parathyroid glands?
four; paired; two inferior, two superior
Where are the parathyroid glands located?
Back of thyroid gland
What is the parathyroid gland involved with?
Maintenance of calcium homeostasis
Where are adrenal glands located?
On top of each kidney
What do adrenal glands do?
Produce corticosteroids and maintain fluid balance
Where is the pancreas located? Where does it extend from?
Posterior to stomach
Extending from duodenum (first part of small intestine) to spleen
What’s the main endocrine function of the pancreas?
To control sugar levels in the blood
What does the physical contact between the hypothalamus and pituitary gland allow for?
Communication between the nervous and endocrine systems
What are the two lobes of the pituitary gland? Give both names for each.
Anterior (adenohypophysis)
Posterior (neurohypophysis)
What is the anterior lobe of the pituitary composed of?
Glandular (adeno) secretory cells
What are the 7 hormones that the anterior pituitary gland secretes?
FLAT PMG
FSH (follicle stimulating hormone)
LH (luteinizing hormone)
ACTH (adrenocorticotropic hormone)
TSH (thyroid stimulating hormone)
PRL (prolactin)
MSH (melanocyte stimulating hormone)
GH (growth hormone)
What do FSH & LH act on? What do they stimulate?
Act on gonads
Stimulate secretion of estrogen and progesterone and maturation of oocytes in ovaries
Stimulate secretion of testosterone and sperm production in testes
What does TSH act on? What does it cause?
Acts on thyroid gland
Causes it to release thyroid hormones
What does PRL do?
Induces mammary glands of the breast to produce milk
What does ACTH act on? What does it do?
Acts on adrenal glands, causing them to release their hormones
What does GH do?
Stimulates growth in all cells
What does MSH do?
Stimulates melanocytes in skin to product pigment
Why is the posterior lobe of the pituitary gland called neurohypophysis?
Made of nervous tissue
What does the posterior lobe of pituitary gland release?
ADH (antidiuretic hormone)
Oxytocin
What is the function of ADH?
Promote reabsorption of water in kidneys
What is the function of oxytocin?
Promote uterine contractions during childbirth and plays role in breastfeeding
True or false: The anterior and posterior lobes of the pituitary differ in their microscopic structure.
True
Which stains darker? Posterior or anterior pituitary?
Anterior
Which is made of glandular acini (small saclike cavities) that are arranged in small groups, surrounded by connective tissue?
Anterior pituitary
What is the anterior pituitary made of?
glandular acini (small saclike cavities) that are arranged in small groups, surrounded by connective tissue
Which part of the pituitary is composed of nervous and connective tissue and does not have acini?
Posterior
What is the posterior pituitary made of?
composed of nervous and connective tissue and does not have acini
What is the word for small saclike cavities
Acini
True or false: The anterior lobe of the pituitary gland releases hormones produced by the hypothalamus
False
True or false: The posterior lobe of the pituitary gland does not produce any of the hormones it releases.
True
True or false: The anterior lobe of the pituitary gland produces and secretes 7 hormones
True
What separates the left and right lobe of thyroid gland?
Isthmus
The microscopic structure of the thyroid gland is composed of many structures called ____________.
Follicles
Each follicle is lined with _________ ___________ follicular cells that surround a central ___________ filled with material called ___________.
simple cuboidal, lumen, colloid
Dispersed between the follicles are the ___________ or ‘C’ cells
parafollicular
What are colloid?
Protein rich fluid secreted by follicular cells of the thyroid gland
Follicular cells are simple cuboidal cells that surround each follicle. These produce two thyroid hormones name them:
T3: Triiodothryonine
T4: Thyroxine
What do T3/T4 do?
Increase rate of metabolism and oxygen consumption
What are the function of C cells? What do they produce? What does this hormone produce?
Calcium homeostasis. Produce calcitonin, a hormone that lowers blood calcium concentration.
What is a physiological condition where the thyroid gland expands in size, causing a large lump in the neck. This can be caused by an excess or lack of thyroid hormones T3 and T4.
Goitre
Along with thyroid glands, parathyroid glands secrete hormones to contribute to _____________________.
Calcium homeostasis
What cells are parathyroid glands mostly made of?
Chief cells/principal
What do principal cells produce (hormone)? What is the function of the hormone?
Parathyroid hormone (PTH); acts to increase calcium ion concentration in the blood
What shape are the adrenal glands?
Pyramids
What is the outer layer of the adrenal gland?
The cortex
What is the inner layer of the adrenal gland?
The medulla
What are do each of the three layers of the adrenal cortex produce?
Outer - produces mineralocorticoids
Middle - produces glucocorticoids
Inner - produces androgens (sex hormones)
What is the core of the adrenal gland called?
Medulla
What hormones does the medulla produce?
Epinephrine
Norepinephrine
The medulla is the core of the adrenal gland, it produces epinephrine and norepinephrine in response to ______________ nervous system stimulation resulting in an ______________ (fight or flight) response.
sympathetic, autonomic
What is the long lobular organ that lies posterior to the stomach?
Pancreas
What does the medial end (head) reach towards (of intestine)?
Duodenum
What does the lateral end (tail) extend towards?
Spleen
What does the pancreas produce enzymes for?
Digestion
What hormones does the pancreas produce?
Insulin and glucagon
What is a mixed gland?
Has both endocrine and exocrine functions
The endocrine functions of the pancreas are the result of specialized groups of cells in the pancreatic ________ or _________ of _________________.
islets, islets, Langerhans
What do the alpha cells produce?
glucagon
What does glucagon do?
Increases blood glucose level
Is glucagon hyperglycemic or hypoglycemic hormone?
hyperglycemic
What do the beta cells produce?
insulin
What does insulin do?
Lowers blood glucose level
Is insulin hyperglycemic or hypoglycemic hormone?
hypoglycemic
What is a possible treatment for type I diabetes?
Treatment with injection of exogenous insulin
Other endocrine functions are associated with… (5)
- Thymus
- Digestive system
- Kidneys
- Gonads
- Heart
