Endocrine System Flashcards
What is a hormone?
Hormones – chemical messengers secreted by endocrine glands
What are target cells?
Target cells – cells that have receptors for a hormone
What are some organs of the endocrine system?
- Pineal gland
- Hypothalamus
- Pituitary gland
- Thyroid gland
- Parathyroid gland
- Thymus
- Adrenal gland
- Pancreas
- Gonads:
i. Testis
ii. Ovary
What are the 3 classes of hormones?
- Steroid hormones
- Monoamines (made from a specific amino acid)
- Peptide hormones
Name some types of hormone secretion stimuli
Neural stimuli – Nerve fibers elicit release of hormones
Hormonal stimuli – Specific stimulating or inhibiting hormones control hormone release
Humoral stimuli – Response to changing levels of certain ions and molecules in blood
How do peptide hormones effect their target cells?
- Bind to surface receptors
- Intracellular processes argue activated
Name 3 types of hormone interactions
Antagonistic
Synergistic
Permissive
Give 2 examples of steroid hormones.
- Sex steroids
- Corticosteroids
2 examples of Monoamine hormones
- Dopamine
- Epinephrine
2 examples of peptide hormones
- Insulin
- Oxytocin
Describe the pituitary gland
Protrusion off bottom of the hypothalamus at base of brain
Name the divisions of the pituitary gland
Anterior
Posterior
Name some hypothalamic hormones
Thyrotropin –releasing hormone (TRH)
Corticotropin-releasing hormone (CRH)
Gonadotropin-releasing hormone (GnRH)
Growth- hormone releasing hormone (GHRH)
Prolactin-inhibiting hormone (PIH)
Somatostatin- growth hormone inhibiting hormone
NE hormone and it’s source is?
Norepinephrine
Source: Adrenal Medulla
OT hormone and its source is?
Oxytocin
Source: Posterior pituitary
PIH Harmon and it’s source is?
Prolactin inhibiting hormones (dopamine)
Source: hypothalamus
PRL hormone, and its source is?
Prolactin
Source: anterior pituitary
PTH hormone and its source is?
Parathyroid hormone
Source: parathyroids
T3 hormone, and its source is?
Triiodothyronine
Source: thyroid
T4 hormone, and its source is?
Tetraiodothyronine
Source: thyroid
TRH hormone and its source is?
Thyrotropin releasing hormone
Source: hypothalamus
TSH hormone and its source is?
Thyroid stimulating hormone
Source: anterior pituitary
ADH hormone and its source is?
Antidiuretic hormone (arginine vasopressin)
Source: anterior pituitary
ACTH hormone and its source is?
Adrenocorticotropic hormone (corticotropin)
Source: posterior pituitary
CRH hormone and its source is?
Corticotropin releasing hormone
Source: hypothalamus
DHEA hormone and it’s source is?
Dehydroepiandrosterone
Source: adrenal cortex
EPO hormone and its source is?
Erythropoietin
Source: kidneys, liver
FSH hormone and its source is?
Follicle stimulating hormone
Source: anterior pituitary
GH hormone and it’s source is?
Growth hormone (somatotropin)
Source: anterior pituitary
GHRH hormone and its source is?
Growth hormone-releasing hormone
Source: hypothalamus
GnRH hormone and it’s source is?
Gonadotropin releasing hormone
Source: hypothalamus
IGF’s hormones and its source is?
Insulin like growth factors (somatomedins)
Source: liver, other tissues
LH hormone and its source?
Luteinizing hormone
Source: anterior pituitary
How do steroid hormones effect their cells?
- Freely enter target cells
- Bind to receptors in the nucleus
Describe an antagonistic hormonal reaction.
One hormone opposes the other
Describe a synergistic hormonal effect.
Two or more hormones act together to produce a greater effect
Describe a permissive hormonal effect.
One hormone, enhances target organs response to the second hormone.
Name 5 of the major organs of the endocrine system
Hypothalamus
Pituitary gland
Thyroid gland
Parathyroid gland
Pancreas
Gonads (testes,ovary)
Adrenal gland
Pineal gland
Thymus
Name two differences between the nervous system and the endocrine system.
The nervous system communicates by electrical impulses and neurotransmitters, endocrine uses hormones
Nervous system has local specific effects endocrine has general widespread effects
Nervous system releases neurotransmitters at synapses, endocrine releases hormones into the bloodstream
Name the divisions of the pituitary gland
Anterior and posterior
What is another name for the pituitary gland
Hypophysis
where is the pituitary gland located?
Protrusion off the bottom of the hypothalamus at the base of the brain
What is the function of the hypophysial portal system?
It connects to hypothalamus to the anterior pituitary
Describe the network of the hypophysial portal system
Primary capillaries in hypothalamus
Portal venues
Secondary capillaries
Name some hypothalamic hormones
Thyrotropin
Corticotropin
Gonadotropin
Growth hormone releasing hormone (GHRH)
Prolactin inhibiting hormones
Somatostatin (growth hormone inhibiting hormone)
Describe the function of GnRH hormone in the ovary
Gonadotropin releasing hormone
Promotes secretion of follicle, stimulating hormone and luteinizing hormone
Describe the effects of TRH hormone
Promote secretion of thyroid, stimulating hormone (TSH) and prolactin (PRL)
Describe the effects of CRH hormone
Promote secretion of adrenocorticotropic hormone (ACTH)
What’s another name for the anterior pituitary gland?
Adenohypophysis
Name some hormones of the anterior pituitary
Follicle-stimulating hormone
Luteinizing hormone
Thyroid-stimulating hormone
Adrenocorticotropic hormone
Prolactin
Growth hormone
What is the target organ of the adrenocorticotropic hormone (ACTH)?
Adrenal cortex
What is the target organs for growth hormone?
Liver, bone, cartilage, muscle, fat
What are the effects of the FSH hormone?
Female: ovarian, follicle growth, estrogen, secretion
Male: sperm production
What are the effects of the LH hormone?
Female: ovulation, maintaining corpus luteum
Male: testosterone secretion
What are the effects of the ACTH hormone?
Growth of adrenal cortex, secretion of glucocorticoids
What is another name for the posterior pituitary gland?
Neurohypophysis
Name some hormones of the posterior pituitary gland
Antidiuretic hormone (ADH)
Oxytocin (OT)
What is another term for the antidiuretic hormones?
Vasopressant
What is the target organ for the antidiuretic hormone?
Kidneys
What is the target organs for oxytocin?
Uterus, mammary glands
What are the effects of ADH hormone? (Think about blood volume)
Water retention
What are the effects of oxytocin?
Labor, contractions, milk release, sperm transport, sexual affection, mother-infant bonding, possibly ejaculation
How do target organs, regulate pituitary, and hypothalamus gland?
Through negative feedback loops
Name some of the mechanisms of the growth hormone and insulin like growth factor hormone interactions. How do they work together to promote growth?
Protein synthesis
Lipid metabolism
Carbohydrate metabolism
Electrolyte balance
What is the location of the pineal gland?
In the posterior portion of the roof of the third ventricle in the brain
What is the hormone the pineal gland secretes?
Melatonin
What is the target organ for melatonin secreted by the pineal gland?
The brain
What is the principal effect of melatonin on the brain?
Not certain
May influence mood and sexual maturation
What is the location of the thymus?
In the mediastinum (center of the chest)
What is the hormone secreted by the thymus?
Thymosin
What is the target organ for the thymosin hormone secreted by the Thymus
T lymphocytes
What is the effect of the thymosin hormone on T lymphocytes?
Stimulates T lymphocytes development and activity
What is the location of the thyroid gland?
Anterior to the trachea
What is the hormone secreted by the thyroid gland?
Triiodothyronine
Tetraiodothyronine (Thyroxine, T4)
Calcitonin
What is the function of calcitonin?
Reduces blood calcium level deposits calcium in bones
What is the target tissue for thyroid hormones?
Most issues and bone
What are the effects of T3 and T4 hormone?
Elevate, metabolic rate and heat production
Increase oxygen consumption by cells
Regulate growth and development
What is the location of the parathyroid gland?
Embedded in the posterior surface of thyroid gland
Which hormone is secreted by the parathyroid gland?
Parathyroid hormone
What are the target tissues for the parathyroid hormone?
Bone
Kidneys
Small intestines
What is the principal effect of the parathyroid hormone?
Raises blood calcium levels
What is the location of the adrenal gland?
On top of each kidney
What are the divisions of the adrenal gland?
Cortex
Medulla
What are some hormones of the adrenal cortex?
Glucocorticoids (cortisol)
Mineralocorticoids (aldosterone)
Sex hormones
What are the target organs of cortisol?
All tissues
What is the target organ of aldosterone?
Kidneys
What are the effects of aldosterone on the kidneys?
Reabsorb sodium, excretes, potassium
Maintains blood pressure and volume
What are the effects of cortisol on the body?
Raises blood glucose level
Stimulates breakdown of proteins
What are the effects of the sex hormones?
Stimulates reproductive organs
Bring about sex characteristics (puberty)
Name some hormones of the adrenal medulla
Epinephrine
Norepinephrine
What are the target organs for epinephrine and norepinephrine?
Cardiac and other muscles
What are the effects of epinephrine and norepinephrine?
Released in emergency situations
Raises blood glucose levels
What is the location of the pancreas?
Below and behind her stomach
Name some hormone secreted by the pancreas
Insulin
Glucagon
Somatostatin
Gastrin
What are the target organs for insulin and glucagon?
Liver
Muscles
Adipose tissue
What are the target organs for somatostatin?
Pancreatic alpha and beta cells
Stomach
Intestines
What is a target organ for the gastrin hormone?
The stomach
What are the principal effects of insulin?
Lowers blood glucose level
Promotes formation of glycogen
What is the principal effect of glucagon?
Raises blood glucose level
Gluconeogenesis
What is the principal effective of somatostatin?
Inhibits insulin and glucagon
Modulate digestion, and nutrient absorption
What is the principal effect of gastrin?
Stimulate acid secretion and gastric motility
What is the location of the ovaries?
Pelvic cavity
Name some hormone secreted by the ovaries
Estrogen
Progesterone
Inhibin
What is the source for the hormone inhibin?
Anterior pituitary
What is the target organ for Estradiol? (Estrogen)
Many tissues
What are the target organ for progesterone?
Uterus
Mammary glands
What are the principal effects of estradiol? (Estrogen)
Stimulates female sex characteristics
Regulates menstrual cycle
What is the principal effect of progesterone?
Regulates menstrual cycle
What is a principal effect of inhibin?
Inhibits FSH secretion
What is the location of the testes?
in the scrotum
What are the hormone secreted by the testes?
Testosterone
Inhibin
What is the target organ inhibin stimulates to effect the testes?
Anterior pituitary
What is the target organ for testosterone?
Many tissues
What are the principal effects of testosterone?
Stimulates male sex characteristics
Sperm production
What are the principal effects of inhibin in the testes?
Inhibits FSH secretion
Name the hormone produced by adipose tissue?
Leptin
Name the hormone produced by osseous tissue.
Osteocalcin
Name two hormones produced by the placenta
Estrogen
Progesterone
Name a hormone secreted by the heart
Natriuretic peptide