Homeostasis 1 Flashcards
<p>What is homeostasis?</p>
<p>The tendency towards a reletively stable equilbrium between interdependent elements</p>
<p>What are our bodies composed of and how are they organised?</p>
<p>Cells---Tissues---Organs---Systems---Organism</p>
<p>What is a tissue?</p>
<p>Groups of cells that show the same characteristics or specialisations</p>
<p>What is an organ?</p>
<p>Collection of tissues, usually of several different types, that collaborate to perform a specific function</p>
<p>What is the basic equation of life?</p>
<p>Nutrients + O2→ Energy (ATP) + CO2+ waste</p>
<p>All living cells require energy to survive</p>
<p>In terms of homeostasis, what happens once energy demand increases?</p>
<p>The supply of substrates required to produce that energy must also increase to maintain homeostasis and prevent a disturbence to the system</p>
<p>Why is maintaining constancy of the internal environment important?</p>
<p>All fundamental physiological processes require a constrant internal environment</p>
<p>How does homeostasis require the integation of organ systems?</p>
<p>Sensory and musculoskeletal supply nutrients</p>
<p>Respiration supplies 02</p>
<p>Alimentary breaks down food</p>
<p>Cardiovascular carries O2and nutrients to cells and removes waste</p>
<p>Renal systems disposes of waste</p>
<p>What systems coordinate the integration of organs?</p>
<p>Nervous and endocrine</p>
<p>At what levels is regulation required to maintain homeostasis?</p>
<p>Cell</p>
<p>Tissue</p>
<p>System</p>
<p>What is physiology?</p>
<p>Our bodies constantly monitoring their internal state and responding to any disruptions in order to maintain homeostasis</p>
<p>What does failure to maintain homeostasis result in?</p>
<p>Illness, disease or pathology</p>
<p>Our bodies are not very tolerable of substantial changes in our internal environment such as?</p>
<p>Temperature</p>
<p>pH</p>
<p>Concentration of hormones</p>
<p>Does our body have a range around optimum level that it can tolerate?</p>
<p>Yes</p>
<p>How is a constant level maintained?</p>
<p>Input must match the output</p>
<p>What are common everyday challneges to homeostasis?</p>
<p>External temperature</p>
<p>Diet</p>
<p>Exercise</p>
<p>What does a chart that shows homeostasis regulation look like?</p>
<p>At extremes homeostasis becomes less effective</p>
<p>What type of control system regulates tissue and organ systems?</p>
<p>Negative feedback control systems</p>
<p>What is the process of a negative feedback control system?</p>
<ol> <li>Change is sensed by receptor</li> <li>Feeds information to integration centre and compares to reference level</li> <li>Any difference generates a signal that is fed to an effector molecule</li> <li>Response is produces that corrects original change</li></ol>
<p>Is the size of the generated signal proportionate to the size of the difference from normal in a negative feedback control system?</p>
<p>Yes</p>
<p>What is the aim of a negative feedback control system?</p>
<p>Return the internal environment to optimal conditions</p>
<p>What are characteristics of a negative feedback system?</p>
<p>Oscillate around a set point</p>
<p>Restores regulated variable after its initial displacement, cannot prevent it from happening</p>
<p>What is a feed forward system?</p>
<p>A more sphisticated form of negative feedback that can prevent change from happening in the first place</p>
<p>What are characteristics of a feed forward system?</p>
<p>Additional receptors allow system to anticipate change and activate a response sooner</p>
<p>To an extent can predict and prevent change</p>
What is positive feedback?
Leads to even greater disturbance
What is negative feedback?
Aims to restore conditions to optimum
Positive feedback is rare in physiology, but where does it occur?
Nerve action potential
Ovulation and sexual behaviour
What is the aim of medicine?
To restore homeostasis control when it is disturbed by illness or disease
