Endocrine System Flashcards
Thymosin
Stimulates T lymphocytes as part of the immune response
Pheromenes
- In urine of a dog
- Carry a message between different individuals of a species
Adrenal Medulla
- epinephrine (adrenaline)
- Nonepinephrine (noradrenaline)
Tropic Hormones
- Hormones that stimulate other glands to release hormones and can have a far-reaching effect
Adrenal Cortex
- STimulated by ACTH to secrete steroid hormones together known as corticosteroids(from cholesterol)
- glucocorticoids
- mineralocorticoids
- cortical sex hormones
What is the endocrine center of the pancreas?
Islets of Langerhans
Parathormone
- Raises blood calcium levels
- regulates calcium and phosphate balance between blood, bone, and other tissues
- Increased horomone increases bone formation
Progesterone
Promotes uterine lining growth
Hormones
Chemical messengers produced in 1 tissue and carried by the blood to act on other body parts
Produced in ductless (endocrine) glands
Pineal
- In brain
- Melatonin
Androgens
Support sperm production and promote secondary sex characteristics of males
Growth Hormone (GH)
Secreted by Anterior pituitary
Stimulates growth of bones and body tissues
Thymus
- In neck
- THymosin
Glucocorticoids
- Secreted by adrenal cortex
- ex/ cortisol, cortisone
- raise blood sugar levels by gluconeogenesis and decrease protein synthesis
- reduce body’s immunological and inflammatory responses
- elevated cortisol repsresses ACTH and lowers cortisol levels, acting as a feedback loop to maintain constant coritsol levels
Hypothalamus
- bridge between the endocrine and nervous systems
- acts part of the nervous system when it sends electrical signals to adrenal gland to release adrenaline
- acts part of endocrine gland when it produces oxytocin and antidiuretic hormone stored in the posterior pituitary
- body’s thermostat
- centers for regulating hunger and thirst
Antidiuretic Hormone (ADH)
Produced by hypthalamus
SEcreted by posterior pituitary
Promotes kidney to reduce water loss
Glucagon
- Secreted by Pancreas
- Raises blood glucose levels
- breakdown glycogen into glucose
Anterior pitutarry
- Growth Hormone (GH)
- Luteininzing Hormone (LH)
- Thyroid-stimulating Hormone (TSH)
- Adrenocorticotropic Hormone (ACTH)
- Follicle-stimulating hormone (FSH)
- Prolactin
FLAT PIG
Insulin
- Secreted by Pancreas
- Lowers blood glucose levels when glucose concentrations are high(like after a meal)
- stimulates muscles and liver to convert glucose to glycogen
Estrogen
- Stimulates uterine lining
- promotes development and maintenance of primary and secondary female characteristics
Oxytocin
Produced by hypothalamus
Secreted by posterior pituitary
Stimulates contractions of the uterus and mammary glands
Ovaries
- Estrogen
- Progesterone
Negative Feedback
- Maintains homeostasis
- ex/ body maintains thyroxin levels. WHen low, hypotalamus stimulates anterior pituitary to release a thyroid-stimulating hormoen to relase more thyroxin
Pancreas
- endocrine function centered in the islets of Langerhans
- Insulin
- Glucagon
Luteinizing Hormone (LH)
- Secreted by anterior pituitary
- Stimulates ovaries and testes
- Induces testes to mature by beginning to secrete testosterone
- stimulates ovulation of the primary oocyte from the follicle
Follicle-stimulating Hormone (FSH)
Secreted by anterior pituitary
Stimulates gonads to prodoce sperm and ova
Melatonin
Secreted by Pineal
Invloved in biorhythms
Andrenocorticotropic Hormone (ACTH)
Stimulates adrenal cortex to secrete glucocorticoids
Feedback Mechanism
A self-regulating mechanism that increases/decreases an action or the level of a substance
Peptide Hormones
- large, hydrophilic, charged
- can’t diffuse across the plasma membrane
- Protein receptors they bind to are located on the cell suface
- activates receptor and causes it to transmit a signal into the cell
- release secondary messengers(c-AMP) in the cell that amplify the signal and alter cell activities
- produced as large inactive pro-hormones that are cleaved by proteases into smaller active peptides before released
- stored in secretory vesicles in the cytoplasm waiting for signal to be dumped out into the blood
- Can act quickly
Flight or Fight Response
- Body’s physical reactions to stress
- epinephrine and norepinephrine increase heartbeat
- increase blood supply to skeletal muscle, heart, braine, while decrease supply to kidneys, skin ,digestive tract
- elicited by sympathetic nervous stimulation
Epinephrine
- Secreted by the adrenal medulla
- fight-or-flight hormone
- neurotranmitter
Thyroxin
- A modifioed amino acid that contains 4 atoms of iodine
- stimulates oxidative metabolism throughout body
- Controls metabolic rate
- Deficiency of thyroxin can cause:
- Goiter(Swelling), decreased heart rate, lethargy, obesity, decreased mental alertness
- too much can cause
- Sweating, high body temp, inceased basal metabolic rate, high blood pressure, weight loss, irritability
Testes
- Androgens
Mineralocorticoid
- Secreted by adrenal cortex
- ex/ aldosterone
- regulte plama levels of sodium and potassium and extracellular water volume
- causes active reabsorption of sodium and passive reabsorption of water in the kidney
Posterior Pituitary
- Oxytocin
- Antidiuretic Hormone (ADH)
- Direct extension of nervous tissue from hypothalamus
Thyroid
- Thyroxin
- Calcitonin
Positive feedback
- Enhances an already existing response
- ex/ Baby’s head against uterine opening sensors cause contractions, which causes more contractions until baby is born
Prolactin
Secreted by Anterior pituitary
Responsible for milk production by the female mammary glands
Parathyroid
- Parathormone
Signal Transduction Cascade
- Indirect signaling by a hormone
- releases secondary messengers in the cell that amplify the signal and alter cellular activites
Steroid Hormones
- small, hydrophobic
- most are derived from cholesterol(lipid)
- can diffuse through cell membrane
- bind to steroid hormone receptors after diffusion
- the receptors enter the nucleus and bind to target regions in genes that regulate transcription, turning the genes on or off
- changes in gene transcription and protein expression
- not stored after production
- Take longer to produce aresponse
Thyroid-stimulating Hormone (TSH)
Secreted by anteriro pituitary
Stimulates thyroid gland to secrete its own hormone, thyroxine
Epinephrine; Nonepinephrine
- Adrenaline; noradrenaline
- neurotransmitters
- Raises blood sugar level by increasing rate of glycogen breakdown into glucose by liver
- increase basal metabolic rate
- increase heart beat
- increase blood supply to skeletal muscle, heart, and brain, while decreasing blood to the kidnesy, skin, digestive tract - “fight or flight response”
Calcitonin
Secreted by Thyroid
Lowers blood calcium levels
