Test Three Flashcards
what is endocrinology
the study of hormones, the glands that secrete hormones, target/receptor organs, and related disorders
endocrinology
the study of how the cells use chemical agents ( hormones) to communicate with each other to adjust bodily functions
function of endocrine system
integrates and regulates bodily functions, providing stability to the internal environment
what is homeostasis
internal environment stability
what is the body’s two major communication systems
nervous and endocrine system
what kind of communication does the nervous system provide
rapid communcation
what kind of communication does the endocrine system provide
longer delays and effects last longer`
the endocrine system consists of
host organ (gland), chemical messengers (hormones), and a target/ receptor organ
can an endocrine gland secrete multiple hormones
yes
what are the functions of the endocrine system
homeostasis
energy regulation (metabolism, during exercise)
growth and development (puberty, aging)
reproduction
what is a hormone
a chemical substance secreted by a specialized gland into the blood where it is carried to target tissue where it binds to specific receptors and exerts a biological effect
hormones bind to receptors located on what
target tissue
what is lock and key
specific hormones bind to specific receptors
where do you find hormone receptors
plasma membrane
intracellular
what are the three types of hormones
amines
steroids
peptides/ proteins
what is the most common type of hormone
peptide/ protein
what are the patters of hormone secretion
pulsatile
cyclical release
episodic
what is pulsatile
released in pulses, frequent
what is cyclical release hormone
circadian/ diurnal (24 hours)
monthly
what is episodic hormone
released in response to certain stimuli
what are the three types of hormone interaction
permissiveness
synergism
antagonism
what is permissiveness
one hormone cannot exert its full effect without the presence of a second hormone or a greater quantity of the first hormone
what is synergism
when hormone A and hormone B are producing the same effects at the target tissue, their combined effects are amplified
what is antagonism
hormone A opposes the action of hormone B
what are the two feedback loops
negative and positive
what is negative feedback
an increase in a hormone brings about a response that decreases the level of that hormone
what is positive feedback
an increase in a hormone brings about a response that increases the level of that hormone
hormones released by the hypothalamus controls what
the release of pituitary hormones
what hormones are released by the hypothalamus
growth hormone- releasing hormone (GHRH) Thyrotropin-releasing hormone (TRH) Corticotropin-releasing hormone (CRH) Gonadotropin-releasing hormone (GnRH) Prolactin- inhibiting hormone (PIH)
what composes the pituitary gland
anterior and posterior pituitary
what hormones are released by the anterior pituitary gland
prolactin (PRL) Growth hormone (GH) Thyroid Stimulating Hormone (TSH) Adrenocorticotropic Hormone (ACTH) Follicle stimulating hormone (FSH) Leutenizing hormone (LH)
what is the main function of prolactin
stimulate milk production after childbirth
prolactin secretion is controlled by
prolactin inhibiting hormone PIH
Dopamine
what is the main function of growth hormone
stimulate tissue growth
growth hormone stimulates what hormone
insulin-like growth factor 1 (IGF-1)
growth hormone is regulated by what hormone
GHRH
what can increase growth hormone
exercise
hyposecretion of growth hormone causes
dwarfism
hypersecretion of growth hormone causes
gigantism and acromegaly
ACTH stimulates what
release of glucocorticoids by the adrenal cortex
high concentrations of adrenocorticotropic hormone does what
causes lipolysis by fat cells and increased melanin synthesis and skin darkening
ACTH is released in response to
stress and low blood glucose concentrations
function of follicle stimulating hormone (FSH)
initiation of spermatogenesis in males
stimulates ovarian follicle development in females
function of lutenizing hormone
enhances testosterone production
stimulates ovulation and estrogen production
what affects LH levels
anxiety
what hormones does the posterior pituitary release
oxytocin and vasopressin (ADH)
function of oxytocin
stimulates muscles in uterus and breast
causes milk ejection in nursing mothers
causes contraction during childbirth (positive feedback)
function of ADH
limits how much urine the kidneys produce
hyposecretion of ADH causes
diabetes insipidus (Frequent urination)
what inhibits ADH
alcohol
what hormones do the thyroid produce
T3 and T4
what is another name for T3
triiodothyronine
what is another name for T4
thryoxine
hyposecretion of TSH causes
cretinism (severely stunted physical and mental growth)
hypersecretion of TSH causes
increase in size of thyroid (goiter)
Function of T3 and T4
stimulates metabolic rate and regulates cell growth and activity
hypersecretion of T3 and T4 causes
decreased metabolism and body temp, cold intolerance, decreased appetite, weight gain, elevated cholesterol, decreased protein synthesis, hypotension, and growth retardation
hyposecretion of T3 and T4 causes
increased metabolism and body temp, heat intolerance, increased appetite, weight loss, hypertension, and muscle atrophy
what hormone does the parathyroid gland release
parathyroid hormone PTH
function of parathyroid hormone
regulates calcium levels in blood
necessary for bone development
hyposecretion of PTH
hypocalcemia
hypersecretion of PTH
leaching of calcium from bones
what are the hormones of the adrenal cortex
cortisol and aldosterone
essential for life
what are the hormones of the adrenal medulla
epinephrine
norepinephrine
not essential for life
function of pancreas
maintain stable blood sugar levels
what hormones do the pancreas release
insulin and glucagon
what specifically secretes insulin
beta cells in pancreas
function of insulin
promotes carbohydrate transport into cells
decrease blood glucose levels
hyposecretion of insulin
type 1 diabetes
hypersecretion of insulin
hypoglycemia, anxiety, nervousness, weakness
what specifically secretes glucagon
alpha cells of pancreas
function of glucagon
increases blood glucose levels
causes liver to release glucose to blood
hyposecretion of glucagon
hypoglylcemia
hypersecretion of glucagon
hyperglycemia
function of the pineal gland
releases melatonin
where is melatonin derived from
serotonin
what type of variation does melatonin have
diurinal
testes secrete what hormone
testosterone
function of testosterone
maintain sex drive, sperm production, male hair patterns, muscle mass, and bone mass
increases rbc production
what controls the secretion of testosterone
FSH and LH
what hormone does the ovaries secrete
estrogen and progesterone
function of estrogen and progesterone
develop and maintain female sex traits
maintain pregnancy
control menstrual cycle
increase fat deposition
what controls the secretion of estrogen and progesterone
LH and FSH
what kind of things can endocrine disorders affect
imbalances in metabolism
impaired growth
high or low bp
loss of fertility
what is hyporesponsiveness
reduced response of the target cells
what is hyperresponsiveness
increased response of the target cells
what is a primary endocrine disorder
occurs in gland that directly secretes the hormone
what is the secondary endocrine disorder
occurs in the gland that controls the primary gland
what is the tertiary endocrine disorder
occurs in the gland that controls the gland that controls the primary gland
where can hypothyroidism originate from
thyroid gland, anterior pituitary or hypothalamus
95% of hypothyroidism is caused by
defect of loss in the tissue of the thyroid gland or due to inadequate iodine intake
with low thyroid hormone levels, what is elevated
TSH
high TSH levels cause what
enlargement of thyroid
goiter
causes of primary hypothyroidism
loss of functional tissue autoimmune thyroiditis reversible autoimmune hypothroidism surgery and radiation infiltrative and infectious diseases thyroid dysgenesis born with small or underdeveloped thyroid
what is hashimotos disease
autoimmune thyroiditis
destruction of thyrocytes
more common in women
how do you treat hashimotos disease
thyroid hormone replacement therapy
sometimes there is spontaneous recovery
what is a treatment for hyperthyroidism
radioiodine
destroys thyroid tissue
most common treatment
what is a potential outcome of thyroid removal
hypothyroidism because not producing the same amount of hormone as before
effects of thyroid deficiencies in children
ossification is delayed
retarding bone age
malformation of facial bones
mental retardation
effects of thyroid deficiencies in adults
decreased cardiac output
decreased sympathetic activity
impaired memory
slowed reflexes
what is graves disease
hyperthyroid autoimmune disease
antibodies in blood stimulate thyroid to grow and secrete too much thyroid hormone
what are some symptoms of graves disease
difficulty sleeping
muscular weakness (upper arms and thighs)
more frequent bowel movements
orbital cavity enlargement causing eyes to bulge forward
how to diagnose thyroid problem
measure serum thyroid hormone levels in blood
TSH will be high, while T4 will be low, suggesting a thyroid problem
primary hypothyroidism
a low TSH level with a low T4 level, suggesting a pituitary problem
secondary hypothyroidism
T3 and/or T4 will be high and a low TSH level may suggest the thyroid is overactive
primary hyperthyroidism
High TSH level causing high T3 and/or T4 levels may suggest the pituitary is overactive
secondary hyperthyroidism
pituitary disorders are caused by
pituitary tumors
what kind of tumors are pituitary tumors
mostly benign
what are non secretory tumors
does not over produce hormones, may cause hyposecretion
but can still cause problems due to its size and location
non secretory tumors cause
headaches and visions problems
how are non secretory tumors found
MRI
hypopituitarism most often affects what hormone first
growth hormone
symptoms of hypopituitarism
depend on hormone
GH: inadequate growth
TSH: hypothyroidsim
ADH: diabetes insipidus
how is hypopituitarism
hormone replacement therapy
male symptoms of hypopituitarism
erectile dysfunction
decrease in facial hair or body hair
female symptoms of hypopituitarism
amenorhea, absence of menstration
infertility
inability to produce milk for breast feeding
stunted growth in children
non tumor causes of hypopituitarism
head injury brain surgery radiation treatment stroke autoimmune disorder infections of the brain tuberculosis genetic mutations
growth hormone excess causes
acromegaly and gigantism
what causes growth hormone excess
pituitary tumor
slow growing
if the pituitary tumor arises after puberty, after growth plates have fused, what occurs
acromegaly
what happens in acromegaly
bones thicken jaw enlarges and forehead thickens enlarged lips, nose and tongue deepening of voice due to enlarged sinuses and vocal cords body organs enlarge joint aches thick, coarse, oily skin skin tags
if pituitary tumor arises before puberty, before growth plates have fused, what happens
gigantism
health consequences to high levels of GH
type 2 diabetes hypertension increase risk of cardiovascular disease arthritis increased risk for colon polyps
diagnosis of GH in pituitary
blood tests ( check GH and IGF-1) imaging
children with GH deficiency will have normal what
intelligence and body dimensions
how does adult GH deficiency occur
damage to pituitary gland or tumor treatment
common symptoms of adult GH deficiency
increased body fat, decreased muscle mass, fatigue, sexual dysfunction
what is addisons disease
adrenal insufficiency from tumors or from autoimmune attack destroying part of the adrenal gland
what is cushings syndrome
excess cortisol in blood
uncontrolled catabolism of bone, muscle, skin, and other organs
signs of cushings syndrome
obesity buffalo hump hypertension diabetes osteoporosis
what is hypergonadism in men
extra X chromosome
decrease testosterone production
primary, secondary of hypogonadism
primary: testicular failure
secondary: FSH/LH failure
development of breast
how many bones in the body
206
functions of the skeletal system
give body shape protect and support organs provide levers on which muscles pull store calcium and other minerals production of blood cells does not generate heat
where are blood cells formed in bones
central marrow cavity
what kind of minerals that make up most of bone weight
calcium and phosphate
what is cortical bone
hard, compact
shafts of long bones, typically surrounds outside of bone
function of cortical bone
mechanical and protective, aid as protective layer
what is trabecular (spongy) bone
loosely organized porous matrix
ends of long bones and within vertebrae
function of spongy bone
metabolic
chemical reactions to maintain living state of cells
what is bone modeling
alterations in the shape of the bone such as changes in length
what is bone remodeling
a constant state of formation and resorption
when does bone modeling occur
ceases around age 18-20
skeleton stops growing
when does bone remodeling occur
throughout life span, but decreases with age
osteoclasts
resorptions
erode old bone
immature bone cells
osteoblasts
form new bone
formation
immature bone cells
which part of the bone remodeling process involves osteoblasts filling in cut away bone
reversal
bone remodeling is what kind of process
coupled
what type of bone remodeling is in healthy adult bones
rate of resorption= rate of formation
what is “uncoupling” bone remodeling
greater resportion with normal formation
abnormally low formation with normal resorption
what are the three types of bone cells
osteoclasts
osteoblasts
osteocytes
what are osteocytes
mature bone cells
osteoblasts become osteocytes
function of osteocytes
become incorporated within the newly found osteoid and eventually become calcified bone
how does estrogen act in ways to increase or maintain bone mass
increases calcium absorption in gut
decreases bone resorption
decreases calcium excretion in urine
main function of vitamin D
stimulate absorption of calcium by the intestine
where can you obtain vitamin D
diet and sunlight
what is osteoporosis
pathological condition associated with a loss of bone mass caused by increased bone resorption and/or decreased bone formation
what is osteoporosis characterized as
decreased bone mineral density and a deterioration of the microarchitecture of bone leading to increased bone fragility and increased risk of fracture
what happens to our bones after age 30
bone breaks down faster than new bone can be formed
why is osteoporosis more common in women
bone loss accelerates after menopause due to decrease in estrogen
have lower bone mass than men
low bone mineral density is often found in what type of women
young amenorrheic
what are the two important factors in the development of osteoporosis
peak bone mass (density)
rate of bone loss
what are risk factors for osteoporosis
advancing age gender hormonal imbalances thing build or small frame inactivity low calcium intake excessive alcohol intake smoking
the primary means of assessing bone health is to
measure bone mineral density
where do you measure BMD
spine, hip (femoral neck), and wrist
what is the most widely technique used to assess BMD
DXA
dual energy X-ray absorptiometry
what are the symptoms of osteoporosis
bone loss occurs without symptoms
nothing until bump and fracture bone
a collapsed vertebrae can initially be felt or seen in the form of
severe back pain, loss of height, or spine deformities
what are the most susceptible bones to fracture with osteoporosis
spine, hip and wrist
how can you prevent osteoporosis
high peak bone mass early in life
diet high in calcium and vitamin D
high intensity weight bearing and resistance training
no smoking or excessive alcohol
what can you take to help with osteoporosis
calcium and/or vitamin D supplementation
hormone replacement therapy
what is a joint
the junction of two or more bones
what are the three types of joints
fibrous
cartilaginous
synovial
what is a fibrous joint
allow virtually no movement
sutures in skull
what is a cartilaginous joint
allow limited movement
intervertebral discs
what is a synovial joint
allow considerable movement
elbow and knee
what joint do you find arthritis in
synovial joint
what are the important features of synovial joints
low friction and large range of motion
what are some aspects of synovial joints
smooth cartilage
synovial fluid
ligaments
cartilage
what covers the ends of each bone at the synovial joint
smooth cartilage
the entire joint is in a capsule filled with
synovial fluid
function of articular cartilage
covers articulating surfaces of the bone
absorbs shock
reduces friction
function of synovial membrane
lines the joint
seals into a joint capsule
function of synovial fluid
lubricates the joint nourishes chondrocytes ( cartilage cells) absorbs shock
what is a meniscus
wedge-shaped fibrocartilage pads
allow for shape variations of joint surfaces and can restrict joint movement
what is bursae
fluid filled sacs that help cushion the friction in a joint
what is a ligament
tough, elastic band of connective tissue surround the joint to give support and limit the joint’s movement
connect bone to bone
what is arthritis
a condition affecting the synovial joint and is characterized by inflammation, varying degrees of degeneration of joint structures and pain
what are the two types of arthritis
osteoarthritis
rheumatoid arthritis
what is the leading cause of disability in later life
arthritis
what are the consequences of arthritis
impaired exercise tolerance decreased flexibility decreased limitations decreased endurance decreased speed decreased proprioception
what is the best thing in maintaining joint function and joint nutrition
dynamic movements
what can adversely affect joint health
insufficient and excessive motion and/or loads
what is osteoarthritis
degenerative joint disease with cartilage deterioration caused by injury and/or overuse
what is a symptom of osteoarthritis
pain and loss of joint movement due to bone on bone contact
manifestations of osteoarthritis
joint may become misshapen over time and bone spurs develop
bits of bone and cartilage may break off
causes and factors of osteoarthritis
aging and/or overuse
repetitive use causes inflammation in cartilage which swells and causes pain
loss of cartilage from friction
genetic component
what is rheumatoid arthritis
begins as autoimmune inflammatory process of the synovial lining of joint
how does inflammation result from in RA
erosion of the cartilage and bone and causes joint destruction
manifestations of RA
joints frequently become red, swollen, painful, and tender
excessive synovial fluid production
synovium thickens with inflammation
symptoms of RA
occurs in symmetrical pattern start at hands and feet fatigue lack of appetite low grade fever muscle and joint ache and stiffness weakness
what can inflammation do to the body
can affect organs and areas of the body other than the joints
what happens with vasculitis in RA
impair blood supply to tissues and lead to tissue death
what happens to average life expectancy of someone with RA
shortens by 3 to 5 years
what are secondary symptoms of RA
anemia hand and feet deformities limited range of motion lung inflammation numbness or tingling paleness skin redness or inflammation swollen glands
is it hard to diagnose arthritis
yes due to overlapping symptoms
what is used to diagnose arthritis
med history
physical exam
blood test
imaging
treatment for arthritis
maintaining physical activity
drugs
braces
exercise
