What tastes Good? Smell and Taste Smell Olfactory

The organs of taste & smell Smell: A.Olfactory membrane: –Contains over 15 million nerve cells (stimulated by odorous substances) B.Conditions needed for odours to be perceived: –Be in a gaseous state –Contain a sufficient number of odorous molecules; in high concentration –Be carried by the air to the olfactory membrane

C. Chain reaction involved in smelling: –Receiver = Nose –It receives the stimuli which are odours –Transformer = Nerve cells of olfactory membrane –They transform the odours into nerve impulses –Conductor = Olfactory nerve –It conducts nerve impulses from the olfactory membrane to the olfactory bulb in the brain –Analyzer = Brain –It analyses incoming nerve impulses from the olfactory nerve The smell part of the brain is in the limbic region, and is connected to feeling and memory.

Taste (the tongue): mainly composed of muscles. covered with a mucous membrane. Small nodules of tissue (papillae) cover the upper surface of the tongue. Between the papillae are the taste buds, which provide the sense of taste. In addition to taste, the tongue functions in moving food to aid chewing and swallowing, It is also important in speech.

Taste (tongue): A.Taste buds or papillae (location & function): –Tongue is a muscular organ that contains most of the body ’ s taste buds B.Conditions needed for tastes to be perceived: –Be in solution in the saliva. –Contain a sufficient number of flavourful molecules –Come into contact with the papillae (taste buds) Video

C. Chain reaction involved in taste: –Receiver = Tongue –Receives the stimuli which is tastes –Transformer = Taste buds –Transforms tastes into nerve impulses –Conductor = Gustatory nerve –Conducts nerve impulses to the taste center of the brain –Analyzer = Brain –Analyzed incoming nerve impulses from the gustatory nerve

D. 4 basic taste sensations: Salty, Sweet, Sour, Bitter Tongue to label Tongue to label