Endocrine Flashcards
what is the endocrine system
is made of organs called glands that produce different hormones
Which system does the endocrine system work with
They work with the nervous system especially the automatic system to control and adjust functions
What are the glands in the brain
Hypothalamus and the pituitary glands
Where is the hypothalamus and the pituitary gland found
there found in the diencephalon
What is the hypothalamus
The hypothalamus secrets hormones that regulate Body temperature,
Blood pressure, Sleep and many more
How does the hypothalamus perform
by directly influencing the autonomic nervous system or by managing hormones. Some hormones that is stored elsewhere send signals to the pituitary glands to either relieve hormones or signal another hormone
What are the five types of hormones in the hypothalamus
Thyrotropin releasing hormone
Corticotropin releasing hormone
Growth hormone releasing hormone
Prolactin releasing hormone
Gonadotropin releasing hormone
What is a pituitary gland
Acts as the body’s master gland ollowing chemical messages from the hypothalamus sends hormones to other glands that then lead to a response
What is the anterior pituitary gland
The anterior pituitary is supplied indirectly with arterial blood provides oxygen and nutrients, this blood transports hormones secreted by the hypothalamus
What are the five types of hormones that are released from the anterior pituitary gland?
Thyroid stimulus hormone
Adrenocorticotropic hormone
Growth hormone
Prolactin
Gonadotropins
Follicle-stimulating hormone
Luteinising hormone
Where does the Thyroid stimulus hormone travel to
to the thyroid gland
Where does Adrenocorticotropic hormone travel to
to the adrenal gland
What is growth hormone
a protein hormone that stimulates growth of bone and muscle in children. It also increases protein synthesis and metabolic processes that lead to growth
What is Prolactin hormone
is protein hormone is essential in lactation in females in males it helps enhance secretion testosterone and production of semen
What is the Gonadotropins hormone
Travels to the gonads – ovaries for females and testes for men
What is the posterior pituitary gland
it is made up of nervous tissue does not synthesise hormones of its own and is a hormone storage area.This network of nerve fibres allows the hypothalamus to transport its hormones to the posterior pituitary gland
What is the hypothalamic–hypophyseal tract
is the posterior lobe that is connected to the hypothalamus by a bridge of nerve axons
What are the two hormones released by the posterior pituitary gland
Vasopressin
Oxytocin
Where is the pineal gland located
located beneath the corpus callosum.
What is the pineal gland main function
to help control the circadian rhythm by secreting the hormone melatonin.
What is circadian rhythm
the body’s internal 24-hour clock that regulates cycles of alertness and sleep by responding to certain changes
What is melatonin
is secreted in response to darkness. Therefore, during the day, its levels decrease due to excess light.
Where is the thyroid gland located
is located on the anterior surface of the neck, just below the larynx and sits in front of the tracheal.
What are the two lobes for the thyroid gland
left and right lobe is connected by the isthmus
What forms the thyroid glands and what do they release
formed of small spherical sacs called thyroid follicles. wall of the follicle consists primarily of cuboidal epithelial cells called follicular cells that secrete two hormones Thyroxine (also called T4)
Tri-iodothyronine (also called T3
What are the main functions of thyroid organs
Regulate growth, development and reproduction,Stimulate metabolic activities.Increase sensitivity of the cardiovascular and nervous system to adrenaline and noradrenaline which are catecholamines
what is another hormone that the thyroid gland releases
calcitonin. This is responsible for regulating calcium homeostasis by decreasing calcium levels
What are they located parathyroid glands
located beneath the thyroid gland there are two pairs 2 superior and 2 inferior
what is the parathyroid hormones
contains epithelial cells called chief cells that produce parathyroid hormone which to increase blood calcium levels Muscle contraction
Transmission of nerve impulses
Blood clotting
Normal action of enzymes
Where is the thymus located
gland sits between the lungs within the mediastinum. It lies anterior and superior to the heart and sits behind the sternum
What is the thymus glands
It is a gland that is part of both the endocrine and lymphatic system.several hormones that collectively are known as thymosins.These play a role in the development and maintenance of normal immunological responses
Where is the pancreas located
located across the back of the belly, behind the stomach.
What is the right side of a pancreas
right side of the organ is called the head is the widest part of the organ and lies in the curve of the duodenum, the first division of the small intestine
What is the left side of a pancreas
left side extends slightly upward (the body of the pancreas) and ends near the spleen which is called the tail.
What are the two pancreas glands
Exocrine and endocrine
What is the exocrine gland
secretes digestive enzymes into a network of ducts that join the main pancreatic duct. This runs the length of the pancreas
What is the endocrine gland
this consists of something called the islets of Langerhans – this secretes hormones into the bloodstream
What is the functional unit for the exocrine
The acinar cell it synthesises stores and secretes digestive enzymes
- Trypsin and chymotrypsin assist with digestion of proteins
- Amylase assists with digestion of carbohydrates
- Lipase assists with breakdown of fats
What are the four types of hormone secreting cell endocrine
Alpha (α) or A cells secrete glucagon
Beta (β) or B cells secrete insulin
Delta (δ) or D cells secrete somatostatin
PP cells or F cells secrete pancreatic polypeptides
What is glucagon - Alpha cells
is released to raise the concentration of glucose and is classed as a catabolic hormone
What is Somatostatin - D cells
This has strong regulatory effects throughout the body as it works to inhibit the release of other hormones
What is Pancreatic polypeptides - F cells
regulates pancreatic secretion activities and impacts liver glycogen storage and gastrointestinal secretion. It also acts as an inhibitor of somatostatin secretion
What is insulin - beta cells
released to lower the concentration of glucose.It also helps blood sugar enter the body’s cells so it can be used for energy.
What is the normal blood glucose
4-8 mmol
What are the main effects of insulin
enhance the utilisation of glucose by various organs and for the purpose of oxidation and energy generation
What are the three insulin antagonists
Glucagon
Adrenaline
Cortisol
What are the main effect of insulin antagonists
Acting on the liver cells to speed glycogenolysis (formation of glycogen to glucose)
Acting on the muscles to speed gluconeogenesis
where is the adrenal glands located
The paired adrenal glands sit superior to each kidney and have a flattened pyramid shape
what are the three zones that the adrenal cortex divides into
Mineralocorticoids
Glucocorticoids
Androgens
What is Mineralocorticoids
this is the outer zone. The main mineralocorticoid is called aldosterone – it is involved in maintaining water and electrolyte balance stimulates re-absorption of sodium ions.
what occurs when aldosterone is secreted
is secreted following the blood’s potassium levels becoming high promotes aldosterone to help stimulate the excretion of potassium in urine
What is the renin-angiotensin-aldosterone system
critical regulator of blood volume, electrolyte imbalance and systemic vascular resistance
what happens when renin is released
low blood volume and salt levels, juxtaglomerular cells release renin into the bloodstream, which helps the liver’s production of angiotensinogen into the hormone angiotensin I.An further enzyme known as angiotensin converting enzyme (ACE) helps convert angiotensin I into the hormone angiotensin II. The lungs contain this.
Aldosterone secretion is stimulated by angiotensin II.
What is anti-diuretic hormone
It is released from the posterior pituitary gland and is secreted in response to decreased blood volume regulate the amount of water in the body by controlling the amount of water the kidneys absorbs
What is glucocorticoids
is the middle zone These include cortisol, corticosterone, and cortisone
These hormones are under the control of the adrenocorticotropic hormone
What is the primary glucocorticoid functions
is cortisol and is predominantly known as the stress hormone
- Increase your body’smetabolismof glucose
- Regulates metabolism of fats and proteins
- Control yourblood pressure
- Reduce inflammation
- Regulates the body’s stress response
What is Androgens
is the inner layer that secretes sex hormones that contribute to growth and reproduction in both men and women
what are the adrenal medulla two hormones
Adrenaline
Noradrenaline
what is Adrenaline and noradrenaline
they potentiate the fight or flight response leading to an array of different affects:
Pupil dilation
Bronchi expanding
Heart rate and blood pressure increases
Liver produces more blood sugar
Digestion and urination ceases
Muscles stimulated
release in response to physical or emotional stress
What are the gonads
In females, these are the ovaries and males, the testes
Where is the ovaries located
the pelvic cavity of females produces several steroid hormones including oestrogen and progesterone
What is oestrogen
It is needed for puberty, the menstrual cycle as well as bone strength
What is Progesterone function
is to prepare the lining of the uterus for a fertilised egg to implant and grow
What is Gonadotropins
include two hormones Follicle stimulating hormone and Luteinising hormone
What is Follicle stimulating hormone
This is a glycoprotein that stimulates the formation of sperm in the testis and the maturation of the ovarian follicles and oestrogen in the ovary
what is Luteinising hormone
This is a glycoprotein that stimulates the production of testosterone in the testis, the ovulation and the secretion of oestrogen and progesterone by the ovary
what is oxtocin
causes the uterine muscles to contract, and when a baby is being breastfed, oxytocin encourages the flow of milk via the breast ducts so that the nipple may expel it.
