Which type of chemical receptor detects bitterness?

Bitter taste is detected by a specific type of chemical receptor known as bitter receptors, which belong to the G protein-coupled receptor family. These receptors are sensitive to a wide range of bitter compounds, which often include alkaloids and other potentially toxic substances. When bitter compounds bind to these receptors on the taste buds, they activate a signaling cascade that ultimately sends signals to the brain, leading to the perception of a bitter taste.

Understanding the role of bitter receptors is important because the ability to detect bitter flavors is thought to have evolved as a protective mechanism against consuming harmful substances, which are often bitter in taste. This makes the detection of bitterness a critical function in our gustatory system.

The other options refer to different types of taste sensations, each linked to their own respective receptors. Salty receptors detect sodium ions, sour receptors respond to hydrogen ions (acidity), and sweet receptors specifically recognize sugars and sweet compounds. Each type of receptor is specialized for its respective taste modality, underscoring the complexity and specificity of our sensory systems.