endocrine system Flashcards
what is a gland
A group of cells specialised to secrete hormones, can be stimulated by change in concentration of a specific substance or by electrical impulses
what are hormones
“Chemical messengers”, substances secreted directly into the blood from a tissue where it is made. carried the body. the hormone only has an effect on certain specific receptors on target organs or target cells.
structure of hypothalamus
The size of a pea, three zones, highly complex
Deep within the brain, below the thalamus , above the pituitary gland
function of Hypothalamus
main link between endocrine and nervous system, maintains a balanced state.
Produces hormones
what is the Hypothalamus responsible for
Responsible for:
- Body temperature
- Blood pressure
- Hunger and thirst
- Sense of fullness when eating
- Mood
- Sex drive
- Sleep
structure and location of the Pituitary Gland
Divided into two sections: anterior lobe and posterior lobe
1.25cm diameter
Connected hypothalamus via the pituitary stalk (bundle of blood vessels and nerves)
base of the brain
function of the pituitary gland
Makes and releases hormones and controls the function of many the endocrine glands
what does the Anterior lobe do
makes and releases:
- Follicle stimulating hormone (FSH)
- Lutenizing hormone (LH)
- Prolactin
- Growth hormone
what does the Posterior lobe do
releases:
- Antidiuretic hormone (ADH)
- Oxytocin
what is the pituitary gland responsible for
Growth
Metabolism
Reproduction
Response to stress or trauma
Lactation
Water and sodium (salt) balance
Labour and childbirth
structure and location of the pancreas
Leaf shaped/tapered organ
five parts
two glands (exocrine and endocrine function
abdomen, behind the stomach and in front of the spine
function of the pancreas
exocrine - helps in digestion
endocrine - regulates blood sugar
islets of Langerhans create and release hormones directly into the bloodstream.
release hormones, especially Insulin and glucagon
what is the structure of the adrenal gland
triangular in a pair, above the kidneys
whats the function of the adrenal gland
secretes hormones involved in regulation of the metabolism and immune system
structure of the thyroid
2 inches long, butterfly shape, in neck
function of the thyroid
produces hormones that regulate metabolism
balance blood calcium levels
thyroxine aids the metabolism
structure of the parathyroid
small, oval shaped
function of parathyroid
produces parathyroid hormone
helps maintain calcium in bloodstream
structure of ovaries
paired oval organs in the lower abdomen on either side of the uterus
function of ovaries
- hormone production
- prepares uterus by releasing hormones
- maintains pregnancy
structure of testes
oval shaped, paired, under penis
function of testes
secretes testosterone
what are circulating hormones
hormones that are released into blood and circulated into all cells in the body
what are local hormones
secreted by tissues and bind to local cells, do not circulate in blood
