Feed forward mechanism..
(A) Feeling thirsty while walking in hot temperature (B) Shivering on exposure to cold temperature (C) Salivation on smelling food (D) Increase blood pressure during supine posture
(C) Feed forward mechanism Feedback mechanism Controller anticipates changes & takes a desired action. No time lag present Examples: - Cephalic phase of gastric acid secretion Increase ventilatory drive in exercise. Change occur in controlled variable & that change is feedback to controller & then the controller takes action Time lag is present. Type: Negative feed back - Kidney body fluid mechanism - Temperature regulation - Baroreceptor mechanism Positive feed back - Circulatory shock - Oxytocin in paurition - Platelet plug / clot formation - LH surge leading to ovulation - Bladder filling to micturition