EEOB 2520 Study Guide - Midterm Guide: Blood Sugar, Homeostasis, Fetal Alcohol Spectrum Disorder
2 May 2018
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What is Physiology?
• How an organism works
• ions move from place to place, how they direct things
• proteins- key component in body, set up reactions
• systems- respiratory, circulatory, renal, etc
• Integration of:
• Anatomy, biology, chemistry, physics
Four Critical Equations
• 1. ATP = ADP + Pi + energy (and vice versa)
• Our currency to spend to get things done
• No deficit spending in body, need the energy to get it done, can't do it without
ATP
• 2. Gluose + O2 + ADP + Pi → ATP + CO2 + H2O + heat
• Our job to make the most currency (ATP)
• 3. CO2 + H2O HCO3- + H+
• Aiding transport of a key gas, but creating a pH issue
• HCO3- is bicarbonate
• H+ = changes the pH of body, but creating a pH issue
• CO2 is hydrophobic, HCO3- is hydrophillic
• The excess CO2 Is responsible for the need to break it down into the bicarbonate
• 4. PV= nRT
• Pressure, Volume, Number of items, Temperature
• key for lungs, blood vessels, etc
• change in pressure, change in volume
• if you increase P then decrease V because they are indirect
Homeostasis
• Formal Definition: a state of reasonable stable balance between physiological variables
such as blood pressure, body temperature, oxygen, glucose and sodium.
• 1-4 figure in book
• y- axis= blood level of glucose/ x- axis= time of day
• Have the same amount of glucose in our body, but then when we eat breakfast, lunch
and dinner, we see spikes in our glucose
• Relatively stable maintenance of a body parameter= dynamic constancy (same thing)
• Dynamic constancy: a given variable like blood glucose or other parameters may vary in
short term, but is fairly constant when averaged over long term
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• Does not mean a variable is in a rigidly constant state but fluctuates in a predictable and
narrow range
• When it is disturbed up or down from the normal range, it is restored to normal
• body parameters are mutually exclusive, just because glucose goes up does not mean
that temperature will go up
Homeostatic Control System
• Formal Definition: Set of interconnected components that keep s a physical or chemical
variable of internal environment within a predetermined normal range of values
• Purpose: keep the parameter at a set point (SP)- keeping it the same
Steady State (SS): parameter at SP
• When the parameter is at the set point, it is SS
• says we are at our set point, to be in SS must be at SP, but can change the SP so have
a different SS
• ex: at SS for glucose before breakfast, then glucose spikes up and are not, etc
For Steady State:
• System is NOT changing --> because we are at target (we are already in the correct
range)
• System REQUIRES energy
• ex: during lecture Bronson's steady state is vertical (standing up), if body starts to go
down, it brings her back up --> but being vertical needs energy (NOT FREE)
• ex: keeping body at 98.6 degrees still requires energy to do so
Equilibrium:
• System is NOT changing
• System DOES NOT REQUIRE energy
SS IS NOT EQUAL TO EQUILIBRIUM
SS is a yes or no question- are you in SS or not? You will always either be in SS or not in SS
SP is a range of numbers that are considered normal or acceptable
Because E is limited, trade offs required!
• To be able to keep one parameter at SS it takes a certain amount of energy, so its using
up energy amount for other parameters
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find more resources at oneclass.com
• steady state is different from equilibrium, in which a particular parameter is also not
changing BUT no input of energy is required to maintain constancy
Homeostatic Control System Cont.
• disturbances from SS
• ex: when eat breakfast, lunch, dinner, glucose is at a disturbance at SS
Reatie → respose= feedak
• Two types of feedback:
• Negative= opposite of disturbance direction (RETURN TO STEADY STATE)
• Formal Definition: An increase or decrease in the variable being regulated brings
about responses that tend to move the variable in the direction opposite to the
direction of the original change
• If the disturbance is to go up, you come back down to SS
• ex: glucose level spikes up from eating, then comes back down afterwards
• ex: a decrease in body temperature will bring about responses that will increase
body temperature back to its original value
• Ex: I push you towards the door, negative feedback brings you back towards me
• More common in bodies
• Positive= continue in disturbance direction (FURTHER AWAY FROM STEADY STATE)
• If disturbance is to go up, you keep going up away from SS
• Accelerates the process, leading to an "explosive" system
• ex: childbirth- keep making contractions stronger and stronger to get baby out,
when SS is no contractions
• ex: platelet aggregation- start bleeding, keep sending more and more platelets
until blood clots
• Negative= good for homeostasis, stops the continuing loss of homeostasis
• Positive= bad for homeostasis, has no intention of stopping
Proatie → preparation= feedforward (FF)
• Definition: Anticipates changes in regulated variables such as internal body temperature
or energy availability, improves the speed of the body's homeostatic response responses,
and minimizes fluctuations in the level of the variable being regulated meaning it reduces
amount of deviation from the set point
• Limits the degree of feedback required
• Less E required
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
What is physiology: how an organism works ions move from place to place, how they direct things, proteins- key component in body, set up reactions, systems- respiratory, circulatory, renal, etc. Atp = adp + pi + energy (and vice versa: our currency to spend to get things done, no deficit spending in body, need the energy to get it done, can"t do it without. Glu(cid:272)ose + o2 + adp + pi atp + co2 + h2o + heat: our job to make the most currency (atp, 3. Pv= nrt: pressure, volume, number of items, temperature, key for lungs, blood vessels, etc, change in pressure, change in volume if you increase p then decrease v because they are indirect. Equilibrium: system is not changing, system does not require energy. You will always either be in ss or not in ss. Sp is a range of numbers that are considered normal or acceptable.
