The Human
endocrine
system
, The Human endocrine system
Nervous system & hormones maintain homeostasis, respond to internal & external changes
Endocrine system consists of endocrine glands, secrete organic compounds (eg. hormones)
Glands do not function in isolation, continuous interaction means of hormone secretions.
All metabolic activities controlled & coordinated by endocrine system.
Exocrine glands
Glands release secretion via ducts to body cavity/outside
(e.g. salivary glands secrete saliva into ducts open mouth cavity)
Endocrine glands
Ductless glands release secretions (hormones) into blood stream.
Blood transports hormones to target organs, fulfil function.
Specific hormones fit in receptors of target organs, enabling response.
Hormones
Organic chemical messengers, most proteins (insulin), some steroids (lipid-like) (eg. testosterone)
Secreted small quantities into blood stream by endocrine glands
Act slow, effects last long time, many hormones have very short lifespan
Transported to target organs (organ effected by specific hormone) via blood.
Has receptors for specific hormone, enabling it to react to hormone
Have regulatory function, stimulating or inhibiting (sIow down).
Do not function in isolation, form integrated system including nervous system.
Type of control & coordination brought by hormones in blood called chemical coordination.
Later broken down in blood cells/lost in urine
Roles of hormones in the hypothalamus
Hypothalamus, above brain stem, almond sized.
Links nervous & endocrine system via pituitary (master) gland/hypophysis
Pituitary gland, pea-sized gland at base of brain
Hypothalamus releases hormone antidiuretic
hormone (ADH), regulates water balance
endocrine
system
, The Human endocrine system
Nervous system & hormones maintain homeostasis, respond to internal & external changes
Endocrine system consists of endocrine glands, secrete organic compounds (eg. hormones)
Glands do not function in isolation, continuous interaction means of hormone secretions.
All metabolic activities controlled & coordinated by endocrine system.
Exocrine glands
Glands release secretion via ducts to body cavity/outside
(e.g. salivary glands secrete saliva into ducts open mouth cavity)
Endocrine glands
Ductless glands release secretions (hormones) into blood stream.
Blood transports hormones to target organs, fulfil function.
Specific hormones fit in receptors of target organs, enabling response.
Hormones
Organic chemical messengers, most proteins (insulin), some steroids (lipid-like) (eg. testosterone)
Secreted small quantities into blood stream by endocrine glands
Act slow, effects last long time, many hormones have very short lifespan
Transported to target organs (organ effected by specific hormone) via blood.
Has receptors for specific hormone, enabling it to react to hormone
Have regulatory function, stimulating or inhibiting (sIow down).
Do not function in isolation, form integrated system including nervous system.
Type of control & coordination brought by hormones in blood called chemical coordination.
Later broken down in blood cells/lost in urine
Roles of hormones in the hypothalamus
Hypothalamus, above brain stem, almond sized.
Links nervous & endocrine system via pituitary (master) gland/hypophysis
Pituitary gland, pea-sized gland at base of brain
Hypothalamus releases hormone antidiuretic
hormone (ADH), regulates water balance
