Which one of the following is an example of negative feedback loop in humans
1. Constriction of skin blood vessels and contraction of skeletal muscles when it is too
cold
2. Secretion of tears after falling of sand particles into the eye
3. Salivation of mouth at the sight of delicious food
4. Secretion of sweat glands and constriction of skin blood vessels when it is too hot
Go through the following table comparing the effect of sympathetic and parasympathetic nervous system. Which one is matched correctly?
       Features              Sympathetic                  Parasympathetic
                                 Nervous System               Nervous System
(1) Pupil of eye Dilates Constricts
(2) Heart rate Decreases Increases
(3) Intestinal                    Stimulates                          Inhibits
     peristalsis
     movement
(4) Salivary                   Stimulates                      Inhibits secretion
     gland                        secretion
Go through the following characterization of Sympathetic and. Parasympathetic Nervous System. 
I. Dilates pupil, 
II.  Heart rate, BP (Vasoconstriction)  Glycogenolysis, dilates bronchi. 
III. Constricts pupil. 
IV. Induces ejaculation. 
V. Gastric secretion,  salivary secretion, peristalsis. 
VI. Erection and urination.
1. Sympathetic - III, V, VI; Parasympathetic - I, II, IV 
2. Sympathetic - I, II, IV; Parasympathetic - III, V, VI 
3. Sympathetic M II, IV, VI; Parasympathetic - I, III, V 
4. Sympathetic - I, III, V; Parasympathetic - II, IV, VI