Mast cells are found in connective tissue and these are modified basophils of blood. They secrete :
(i) Heparin - plood coagulant
(ii) Histamine - vassodilator
(iii) Serotonin - vasso constrictor.
Plasma cells are present in connective tissue and they synthesize antibodies.
Goblet cells : These are mucus producing glands like cardiac gland of stomach.