homeostasis general Flashcards
what is homeostasis
maintanence of constant internal environment
what is the internal environment made from
the tissue fluid that bathe each cell
what does it ensure of cells
that it is in an enviroments that meets their requirements despite external enviroemtnal changes
what does homeostasis do to the changes
it return the environment to the optimum point
what affect enzyme activity
the changes in ph and temperature
why
it can change the tertiary shape and the shape of the active site decreasing the amount of ez complexes formed
what can changes in water do
change the water potential in the cell causing it to expand or shrink
what also can affect water potential
the glucose and salt concentration
why can organism that control internal environment more versatile
as they can survive in greater geographical location and more times of the day are awake and active
what is the control mechanism
there is an optimum point which is montiroed by the receptor
when the receptor detects a changes which deviates from optimum
informs the coordinator which produces infor which is sent to the effector returning to optimum
what is negative feeback
when conditions change from the optimum point and corrective mechanism turned on to restore the optimum conditons
what is positive feedback
when a deviation form the optimum causes a change that leads to even greater deviation from the optimum
give an example
the influx of sodium ions into the axon increase until threashold
why do we need to maintain glucose concentration
to maintain water potential of a cell and to ensure enough respiratory substrate to make atp
what does control mechanisms allow
produce positive movement towards optimum condition
