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What is defined as "maintaining stable internal conditions"
homeostasis
what do you call your heart rate when you are not exerting yourself?
resting heart rate
This OPPOSES a change to your internal conditions
negative feedback (loop)
TODAY you learned that the the pituitary gland is what part of the positive feedback loop?
effector
What mechanism AMPLIFIES and pushes a condition out of homeostasis?
positive feedback (loop)
Name 4 internal conditions that humans must keep stable
temperature, water balance, pH, blood sugar, electrolytes, heart rate, many others
How can you prove that humans maintain homeostasis of their heart rate?
measure heart rate before and several times after exercise, see if it stays high.
give 2 examples of negative feedback
thermoregulation, blood glucose control, water balance, there are many
sweat glands and the liver are examples of this part of a negative feedback loop
effector
Name 3 positive feedback loops
childbirth, blood clotting, fruit ripening
What is the difference between set point and range and which is the focus of standard #2?
Set point is more exact than range. In homeostasis, it is ok to stay within a range.
When graphing the homeostasis of exercise, what is the independent variable? (horizontal axis)
time
What part of your body is like the thermostat in your home?
Brain/hypothalamus
name a response we learned about in thermoregulation
shivering, blood vessels constricting or dilating
why can't thermoregulation be controlled by a positive feedback loop?
Your temperature would go up until all organs failed.
What two body SYSTEMS help you to maintain a stable internal temperature?
Integumentary, Circulatory, (muscular . . .)
what 3 functions of Homer had to be kept in range?
temperature, electrolytes, fluid balance
Decisions on what to do to correct imbalance are made by two body systems. Which two?
Nervous, Endocrine
This part of a feedback loop detects changes (in internal conditions)
receptor
Ethylene is to ripening as _______ is to childbirth.
Oxitocin
What organelle helps the amoeba maintain water balance? (yes, they have homeostasis too!)
contractile vacuole
what was one of Homer's set points?
example: temp 24 degrees, water at top of eyeball
What does the pancreas tell your liver to do if you have hypoglycemia (low blood sugar)?
release some of your stored sugar
what do clot forms, uterine contractions, sugar entering cells, and shivering all have in common?
They are RESPONSES in a feedback loop
Why does the blood clotting process have to be amplified (+ feedback) rather than opposed (- feedback)?
Blood loss will result in death - the injury has to close completely and stay closed.