Endocrine Flashcards
Functions of the endocrine system
Regulates internal functions
Responds to stimuli to maintain homeostasis
Hormones
Chemical messengers
- endocrine
- exocrine
Hypothalamus
Both nervous tissue and endocrine gland
Controls glands via the pituitary gland which it controls via hormones
Hypothalamus hormones
To the posterior pituitary
- oxytocin
- antidiuretic hormone
To the anterior pituitary
- hypothalamic releasing hormone
Function of tropic hormones
Hormones that are released by a gland and travel to another gland to stimulate them to release another hormone
Tropic hormones
TSH
FSH
LH
ACTH
Glands
Hypothalamus
Pituitary
Thyroid
Parathyroid
Adrenal
Pancreas
Pituitary gland location
Located under and controlled by the hypothalamus
Connected by a stalk called the infundibulum
Anterior pituitary hormones
- stimulated by hormones from the hypothalamus
Growth hormone
Prolactin
Thyroid Stimulating Hormone
Adrenocorticotropic Hormone
Follicle Stimulating Hormone
Luteinizing Hormone
Posterior Pituitary Hormones
- stimulated by nerve impulses
Oxytocin
Antidiuretic Hormone
Growth Hormone (GH)
No target cell
Effects all cells
Causes cells to increase in size and number
Higher levels in puberty
Prolactin
Affects mammillary glands
Influences milk production
Highest levels after childbirth
Thyroid stimulating hormone (TSH)
Stimulates the thyroid to release thyroid hormone
Adrenocorticotropic Hormone (ACTH)
Stimulates the adrenal cortex to produce and release cortisol
Follicle stimulating hormone (FSH)
Targets sex hormones
Stimulates sperm and egg production
Luteinizing hormone (LH)
Targets sex organs
Stimulates ovulation and testosterone
Oxytocin (OT)
Targets the uterus
Stimulates contractions for childbirth
Targets mammillary glands
Sperm release and transport
Facilitates emotional bond between mom and infant
Antidiuretic Hormone (ADH)
Targets the collecting duct in the kidney
Affects water re-absorption
Increases blood pressure by adding water o the blood
Pancreas
Exocrine and endocrine gland
Pancreatic islet cells produce cells
Pancreatic hormones
Beta cells
Alpha cells
Beta cells
Produce insulin
Lowers blood glucose levels and stores glucose in cells
Alpha cells
Produce glucagon
Release glucose into the bloodstream
Thyroid gland structure
Follicles
Colloid
Parafollicular cells
Thyroid follicle hormones
Thyroxine (T4)
- four iodine molecules
Triiodothyronine (T3)
- three iodine molecules
Thyroid follicle hormone functions
Non specific
Increase metabolism
Increase body temp & weight
Increase cardiac output and respiratory rate
Stimulate appetite
Colloid
Stores the hormones that the follicle produces
Newly like structure in the middle of the follicle sack
Thyroid Parafollicular cells
Cells found between the follicles
Produce calcitonin
Calcitonin
Decreases levels of blood calcium by stimulating osteoblasts
Restricts osteoclast activity
Mostly active in kids
Parathyroid glands
Four small glands on the posterior of the thyroid
Release parathyroid hormone in response to low calcium levels
Parathyroid hormone (PTH)
Increases blood calcium levels through the stimulation of osteoclasts
Adrenal glands
Paired glands that sit on top of each other
Adrenal gland sections
Medulla
- inner layer
Cortex
- outer layer
Adrenal cortex zones
Outer to inner
Zona glomerulosa
Zona fasciculata
Zona reticularis
Adrenal cortex hormones
Aldosterone (outer zone)
Cortisol (middle zone)
Androgens (inner zone)
Aldosterone
Regulates electrolytes
Influences water volume and blood pressure
Cortisol
No target tissue
Released in response to ACTH under stressful circumstances
Regulates metabolism
Stimulates glucose production
Androgens
Sex steroids
Influences sexual behavior
Stimulate hair growth
Sustains bone mass in adults and bone growth in kids
Adrenal medulla hormones
Epinephrine
Norepinephrine
Adrenal hormones function
Gluconelgenesis: production of new glucose molecules
Glycogenlysis: breakdown of glycogen
Increase cardiac output
Increased ventilation
