Patho Hesi 2021. Revision Questions ans answers. Rationale provided. Graded A+

An initial disturbance in a system sets off a chain of events that does not favor stability and often abruptly displaces a system from its steady state: what is that? A. positive feedback B. negative feedback C. disease D. homeostasis - A. Positive feedback Positive Feedback - -less common - Snowball Effect (some pain/ pressure gets worse and worse) - examples: clots, sneezing, childbirth - when childbirth starts there is an increase in hormone production which progressively gets worse - May use many means to correct one imbalance(NOT stable) - Moves away from equilibrium amplifies change more of a product = more contractions, more clotting factors Negative Feedback - - more common - self regulating system that helps keep the balance (increase or decrease of output/production) - If there is not enough it makes more, if there is enough it stops making it - resist any changes from normal (example = glucose and temp regulation)-example: thermoregulation- body temp decreases, heating mechanisms activated (shivering), body temp increases , cooling mechanisms activated (sweating) reduces change Disease - - the disruption in homeostasis or deviation from normal - body is no longer functioning normally - cellular process leads to disease Homeostasis - - dynamic process that is always shifting/changing (give and take system) - the body likes things just so (temp, pH, dilution, shape) - equilibrium is necessary for all cells - stable process, self regulating - can affect proteins to be in proper function/ form, release of oxygen in the muscles What organ shrink