Taste Flashcards
<p>List the 5 basic tastes</p>
<p>sweet salty sour bitter umami (‘oo-ma-me’, savoury or meaty).</p>
<p>How does the brain detect and discriminate between tastes</p>
<p>chemicals in food bind to receptors called taste cells that are found in taste buds on the tongue. Taste buds (of which there are around 5000 on your tongue, each containing around 50 taste cells) are embedded in specialised epithelium that forms structures called papillae.</p>
<p>List 4 types of papillae and their functions</p>
<p>Fungiform papillae are small red dots on the tongue that are sensitive to sweet and salt/sour tastes; they are innervated by a branch of the facial nerve (cranial nerve VII).
Foliate papillae are sensitive to bitter tastes; they are innervated by the glossopharyngeal nerve (cranial nerve IX).
Circumvallate papillae detect bitter tastes; they are innervated by the glossopharyngeal nerve (cranial nerve IX).
Filiform papillae do not house taste buds, but are used to create friction and grip food and they help detect food texture; they are innervated by the glossopharyngeal (IX) and facial (VII) nerves.</p>
<p>Why is the texture of the top of your tongue is different from the texture underneath</p>
<p>The top surface of the tongue is in contact with the things you eat and therefore contains the papillae which detect different tastes and textures. The underneath of the tongue is important for shaping the tongue during swallowing and speech and therefore has a higher content of skeletal muscle cells and a different appearance.</p>
<p>What chemical action produces the characteristic taste</p>
<p>Binding of specific ions to the taste receptors produces the characteristic taste. For example, a sour taste is detected by hydrogen ions, salty taste is the detection of metal ions (e.g. sodium and potassium), and a sweet taste comes from the ability to detect sugars.</p>
<p>Describe how a taste sensation is relayed to the brain.</p>
<p>Afferent nerve fibres extend from the base of the taste bud and synapse with multiple receptor cells. These afferent pathways send taste information to the medulla from which the information is relayed to the gustatory centres of the brain. Signals sent to the thalamus and then on to the primary gustatory cortex (located in the frontal lobe) are involved in the perception of taste. </p>
<p>What determines the behavioural response to taste</p>
<p></p>
<p>Information sent to the limbic system determines the behavioural responses to taste. The communication between the medulla, which contains the vomiting centre of the brain, and the limbic system is partly responsible for why you may feel repulsed by and actively avoid eating something that made you throw up after you first ate it (taste aversion).</p>
What other receptors are located on the tongue
Temperature, pressure, pain
