Endocrine System Flashcards
Endocrine system function
The endocrine system regulates how much of each hormone is released
Effector is
something that performs the action
Melatonin is produced by
pineal gland
Melatonin also:
makes you sleepy, reduces cell damage that can lower the risk of cancer and heart disease, and combats diabetes and obesity.
Melatonin sleep cycle:
teenagers secretion at 11pm, adults at 9pm, melatonin stops at 730 for adults, 9 30 for teenagers
Hormones are created by:
organs called glands
Hormones are released and delivered:
through and into the bloodstream
Hormones send:
different signals to the body
Specific receptors are:
in specific places and are usually close to the receptor
Nervous system sends messages:
quick but short lasting, endocrine is slower but very long lasting
Exocrine glands:
send messages outside the body
Pineal gland location
Brain
Pituitary gland location
Brain (below hypothalamus)
Thyroid Glands location
neck
Adrenal glands location
On top of both kidneys
Pancreas gland location
Behind the stomach
Testicle location
Below the penis in the scrotum
Ovaries location
left and right side of the uterus
Some hormones act
general (all cells) or specific effects (certain organs)
hypothalamus location
brain
parathyroid location
neck, makes calcium
thymus location,
in the chest between the lungs
Hormones are
secreted in very small quantities
Hormones have a specific chemical
structure and shape that chemically fit onto receptors so they do not trigger the wrong receptors
The endocrine system is coordinated
coordinated by the pituitary gland which responds to hypothalamus
Hypothalamus…
constantly checks the internal environment, if the conditions change the hypothothalamus respodns (temperature, metabolism, water content).
How does body respond to high and low temperature (veins)
dilating vessels (cold air) to increase heat loss and contract (hot air) to decrease heat loss
When low temperature (skin)
goosebumps are created and hairs stand up on end
homeostasis
The process of maintaining constant internal environment
feedback system
a response within a system that influences the continued activity or productivity of that system
Duiretic
causing increased passing of urine
Low water content level
Hypothalamus detects little water in blood, message is sent to pituitary gland to start production or increase production of ADH
High water content level
Detects High levels, stop ADH production, low levels of a ADH going to kidneys, little water absorbed back into the blood, large uncontentrated urine
Ectotherm
body temperature changes with the temperature of the environment. cannot maintain body temperature
Endotherm
Internally generated heat to maintain body temperature
Negative feedback
Variable triggers a counteractive response to maintain homeostasis
Positive feedback
Variable triggers a response that reinforces the change detected
Hypothalamus acts on the
pituitary gland which acts on the thyroid gland
Thyroxine triggers increased metabolism which
generates more heat and warms the body
Endoctine system does not have immediate
immediate control over body temperature
Body temperature is both controlled by the
nervous and endocrine systems
Hypothalamus when cold sends out
nerve impulses around vital organs to begin small contraction and shaking in these muscles.
Shivering effect
increases activity of muscle cells, producing heat and raising body temperature
If temperature is too low (blood flow)
the blood flow is reduced further and you can lose feeling in them.
Glucose decrease
pancreas releases glucagon which triggers the liver to break down glycogen and release glucose
Glucose too high
pancreas releases insulin making ebody cells take up glucose and liver store as glycogen
What two major systems are used to achieve homeostasis
Nervous and endocrine
