NUR 339 Exam 4
- What is homeostasis?
Answer level of constancy maintained by body during time of change
- What are used to maintain homeostasis?
Answer control systems (there are thou- sands in the body)
- What is an example of a control system?
Answer blood glucose
- What are feedback mechanisms?
Answer self-regulating mechanisms which control homeostasis
- What are the 3 components of feedback mechanisms?
Answer sensor mechanism, control center, effector mechanism
- What does the sensor mechanism component of the feedback mechanism do?
Answer senses disruption
- What does the control center component of the feedback mechanism do?-
Answer regulates response of the body (usually through the CNS)
- What does the effector mechanism component of the feedback mechanism do? 1 / 3
Answer acts to restore homeostasis (the sympathetic nervous system is an effector mechanism)
- What does negative feedback do?
Answer When a function increases or decreases, feedback causes opposite action and stops action when function returned to normal (corrects deficit in system)
- What are examples of negative feedback loops?
Answer increased blood sugar, increased blood osmolarity
- What does a positive feedback loop do?
Answer takes original response and exag- gerates it (these are rare)
- What is an example of a positive feedback loop?
Answer intensification of contrac- tions during labor caused by increased oxytocin
- What are the 3 structures of the brain responsible for homeostasis?
Answer -
medulla oblongata, pituitary gland, reticular formation
- What does the medulla oblongata do for homeostasis?
Answer controls vital func- tions such as circulation and respiration
- What does the pituitary gland do for homeostasis?
Answer controls function of other endocrine glands which regulates growth, reproduction and maturation 2 / 3
- What does the reticular formation do for homeostasis?
Answer network which regulates vital reflexes of CV and respiratory function
- What is the key to adaptation?
Answer responses are efficient and effective (short term rather than long-term)
- What does a maladaptive stress response cause?
Answer disease
- What are the 3 stages of Selye's GAS syndrome?
Answer Alarm stage, resistance, exhaustion or recovery
- What chemicals are released during the Alarm stage?
Answer catecholamines and cortisol
- What happens during the alarm stage?
Answer generalized stimulation of SNS and HPA axis, the body senses stress, CNS is aroused, body releases chemicals to initiate fight-or-flight response, activation of defensive abilities
- What are manifestations of the alarm stage?
Answer increased heart rate, de- creased stroke volume, dilated pupils, sweaty palms, increased mental acuity
- What happens during the resistance stage?
- / 3
Answer