Ch. 16 - Endocrine System - CLASS NOTES Flashcards
What is the second controlling system of the body?
Endocrine system
Hormones are also called:
chemical messengers
Hormones control 5 processes
reproduction growth and development mobilization of body defences homeostasis regulation of metabolism
5 effects caused by hormones
changes in plasma membrane permeability protein synthesis enzyme activation/inactivation mitosis stimulation secretory activity
hormones are produced by _____ cells
specialized
cells secreted hormones into _______ fluid
extracellular
hormones are transferred to target sites by the _______
blood
hormones _______ the activity of other cells
regulate
3 main hormone classifications
- steroids - can go through cell membrane
- non-steroids
- prostaglandins
hormones affect only certain _____ or ______
tissues, organs
target cells must have specific protein ________
receptors
2 mechanisms in which hormones act:
- direct gene activation (steroid)
2. second-messenger system (non-steroid)
direct gene activation (steroid)
- can go through plasma membrane
- enter nucleus
- activate genes & DNA
- effects can take 45 minutes to days
second messenger system
- cannot pass through membrane
- uses a receptor protein
- faster (seconds to minutes)
3 hormone stimuli
- hormonal
- humoral
- nerve impulses (sympathetic)
hormone levels in the blood are mostly maintained by __________ feedback
negative
what does hormonal stimuli mean & give example
hormone release stimulated by other hormones
- pituitary gland targets thyroid gland
what is humoral stimuli & give example
hormone release stimulated by body fluids & blood
- insulin is produced based on blood sugar
what is neural stimuli & give example
hormone release stimulated by nerve impulses
- release of adrenaline
8 major endocrine organs
- pituitary gland & hypothalamus
- pineal gland
- thyroid gland
- parathyroid gland
- adrenal gland
- thymus gland
- pancrease
- gonads
this gland is the size of a pea
pituitary gland
hangs by a stalk and connected to the hypothalamus
pituitary gland
pituitary gland has 2 functional lobes
anterior pituitary - glandular tissue
posterior pituitary - nervous tissue
what gland is known as the “master endocrine gland”
pituitary gland
how many hormones does the anterior pituitary gland secrete
6
2 anterior pituitary hormones that affect non-endocrine targets:
- growth hormone
2. prolactin
4 anterior pituitary hormones that affect endocrine targets - called tropic hormones:
- thyroid-stimulating hormone
- adrenocorticotropic hormone (ACTH)
3 & 4. gonadtropic hormones (FSH & LH)
3 characteristics of anterior pituitary hormones:
- proteins
- second-messenger sytems
- mostly regulated by negative feedback
general metabolic hormone
GROWTH HORMONE
growth of skeletal muscles and long bones
GROWTH HORMONE
causes amino acids to build proteins
GROWTH HORMONE
causes fats to be broken down for energy
GROWTH HORMONE
spares glucose to maintain blood sugar homeostasis
GROWTH HORMONE
3 main kind of GROWTH HORMONE disorders
- pituitary dwarfism
- gigantism
- acromegaly
stimulates milk production following childbirth
PROLACTIN
regulates endocrine activity of the adrenal cortex
ADRENOCORTICOTROPIC (ACTH)
influences growth and activity of thyroid gland
THYROID-STIMULATING HORMONE (TSH)
2 gonadtropic hormones
- FSH
2. LH
stimulates follicle development in ovaries and development of sperm in testes
FSH
triggers ovulation of egg in females and production of testosterone
LH
hypothalamus is regulated by what gland
PITUITARY
2 Hormones of posterior pituitary gland:
- oxytocin
2. ADH
stimulates contractions of uterus during labour
OXYTOCIN
causes milk ejection
OXYTOCIN
induces labour
OXYTOCIN
causes a positive feedback loop
OXYTOCIN
promotes water absorption
ANTIDIURETIC HORMONE (ADH)
drinking alcohol inhibits the secretion of this hormone
ANTIDIURETIC HORMONE (ADH)
this gland hangs from the roof of the third ventricle of the brain
PINEAL GLAND
secretes MELATONIN
PINEAL GLAND
establishes sleep cycle
PINEAL GLAND
affects moods - serotonin
PINEAL GLAND
seasonal affective disorder (SAD)
PINEAL GLAND
this gland is found at the base of the throat and consists of 2 lobes
THYROID GLAND
thyroid gland produces 2 hormones
- thyroid hormone
2. calcitonin
this hormone is the major metabolic hormone
THYROID HORMONE
increases rate of metabolism of all cells
THYROID HORMONE
important in process of normal tissue growth and development
THYROID HORMONE
targets all cells in the body
THYROID HORMONE
3 examples of THYROID disorders
- GOITER (enlarged thyroid)
- MYXEDEMA (physical and mental fatigue)
- GRAVE’S DISEASE (increased metabolism
decreases blood calcium levels by depositing in into the bone and increasing calcium storage
CALCITONIN
opposite to parathyroid hormone
CALCITONIN
tiny masses on posterior of thyroid
PARATHYROID GLAND
parathyroid gland secretes this hormone
PARATHYROID HORMONE (PTH)
removes calcium from bones to raise calcium in blood
PARATHYROID HORMONE
2 hormones involved in calcium homeostasis
- calcitonin
2. parathyroid hormone
these glands sit on top of the kidneys
ADRENAL GLANDS
2 parts of the adrenal glands
- adrenal cortex
2. adrenal medulla
3 hormones secreted by adrenal cortex
- mineralocorticoid (ALDOSTERONE)
- glucocorticoids (CORTISOL)
- gonadocorticoid (ANDROGEN - sex hormone)
hormone produced from adrenal cortex that regulates mineral content
MINERALOCORTICOID
hormone produced from adrenal cortex that helps resist long-term stressors by increasing blood glucose levels
GLUCOCORTICOID - CORTISOL
sex hormone produced by adrenal cortex
GONADOCORTICOID - ANDROGEN
2 adrenal cortex disorders
- ADDISON’S DISEASE (bronze skin)
2. CUSHING’S SYNDROME (buffalo hump)
2 hormones produced by adrenal medula
- epinephrine (adrenaline)
2. norepinephrine (noradrenaline)
adrenaline & noradrenaline are part of the ‘fight or flight’ response of the _________ nervous system
sympathetic
short-term stress hormones:
- epinephrine & norepinephrine (adrenaline)
long-term hormones:
- mineralcorticoids
- glucocorticoids (cortisol)
2 hormones produced by pancreatic islets
- insulin
2. glucagon
this hormone lowers blood sugar levels
insulin
this hormone increases blood sugar levels
glucagon
2 hormones involved in blood sugar homeostasis
glucagon and insulin
2 types of diabetes caused by homeostatic imbalance
- diabetes type 1 - requires insulin
2. diabetes type 2 - insulin resistant
this gland is located posterior to the sternum
THYMUS GLAND
this gland is largest in infants and then atrophies as we age
THYMUS GLAND
this gland produces THYMOSIN
THYMUS GLAND
this hormone is important in developing immune system
THYMOSIN
2 GONAD glands
- ovaries
2. testes
2 hormones present in OVARIES
- estrogen
2. progesterone
hormone present in testes
- TESTOSTERONE (an androgen)
this hormone promotes and maintains female sexual characteristics
ESTROGEN
this hormone acts with estrogen to bring about menstrual cycle
PROGESTERONE
helps in the implantation of embryo
PROGESTERONE
helps prepare breasts to lactate
PROGESTERONE
regulation of ovarian hormone secretion depends on changing levels of these 2 hormones
FSH & LH
this is the most important androgen
TESTOSTERONE
this hormone is responsible for adult male sex characteristics
TESTOSTERONE
this hormone promotes growth and maturation of male reproductive system
TESTOSTERONE
this hormone is required for sperm cell production
TESTOSTERONE
this organ produces hormones that are present only during pregnancy
PLACENTA
this hormone produces human chorionic gonadotropin (hCG) - detectable by pregnancy tests
PLACENTA
hormone produced by the heart
atrial natriuretic peptide (ANP)
ANP is antagonistic to what 2 hormones
ADH and aldosterone