
Concept explainers
(a)
To explain: The model that supports following statement, “previous work had shown that different taste receptor proteins are expressed in non-overlapping sets of taste receptor cells”.
Introduction:
Protein is a
(b)
To determine: The issues that address this experiment and also conclude its results.
Introduction:
Sensory cells are the type of cells that receive information from external stimuli with the help of receptors found their surface. This external stimulus is transmitted from sensory cells to brain through nerves.
(c)
To determine: Whether the given data is consistent with umami taste receptor that consists of heterodimer of T1R1 and T1R3.
Introduction:
Taste receptor T1R1 is a G-protein coupled receptor while T1R3 contains subunit of both sweet taste receptor and umami taste receptor. Taste receptors are type of receptor cells that helps to stimulate taste sensations.
(d)
To determine: Which model of taste encoding supports this result.
Introduction:
Tongue is the muscular organ found in the mouth. It contains taste buds which is consist of taste receptors such as sour, salty, bitter, sweet and umami. The taste receptors help to determine the different taste of food.
(e)
To determine: Whether the given data is consistent with sweet taste receptor of a heterodimer consisting of T1R2 and T1R3.
Introduction:
Taste receptors are defined as type of receptor that facilitates sensation of taste. They are found in taste buds and taste receptor cells are also known as gustatory cells. They are located around small structures on tongue called papillae.
(f)
To determine: How high sucrose concentration complicate idea of heterodimeric system.
Introduction:
Sucrose is a carbohydrate (disaccharide) which is made up of glucose and fructose monomeric units. It is a type of non-reducing sugar. It is obtained naturally by plants. It is found in leaves, fruits, flower and roots of plants.
(g)
To determine: Whether the results of the experiment provides strength to the conclusion about the mechanisms of taste sensation.
Introduction:
Sensory organs include, nose, ear, eyes, skin and tongue. It contains receptors that are specialized cells and able to convert external and internal stimuli into nerve impulse which is transmitted to brain and interpreted into information.

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Chapter 12 Solutions
EBK LEHNINGER PRINCIPLES OF BIOCHEMISTR
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