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>
<p>What is positive feedback?</p>
<p>Leads to even greater disturbance</p>
<p>What is negative feedback?</p>
<p>Aims to restore conditions to optimum</p>
<p>Positive feedback is rare in physiology, but where does it occur?</p>
<p>Nerve action potential</p>
<p>Ovulation and sexual behaviour</p>
<p>What is the aim of medicine?</p>
<p>To restore homeostasis control when it is disturbed by illness or disease</p>
