Odor

Physiology of Smell and Olfactory Perception:

• Odors are caused by volatilized chemical compounds in low concentrations.
• Olfactory receptor neurons in the nasal cavity detect odorous molecules.
• Olfactory information is processed in the brain to relate smells to past experiences.
• Odor identification varies among individuals and decreases with age.
• Women generally outperform men in odor discrimination.
• Pregnant women may experience increased smell sensitivity.
• Sense of taste diminishes with age as smell dominates.
• Chronic smell problems typically increase with age.

Smell Acuity in Humans and Animals:

• Humans have 350 functional olfactory receptor genes.
• Humans can distinguish around one trillion unique aromas.
• Smell is a primary evolutionary sense aiding in survival.
• Experienced individuals can identify chemicals in complex mixtures.
• Human sense of smell is comparable to many animals.

Habituation and Adaptation in Odor Perception:

• Habituation makes familiar odors less noticeable.
• Continuous odor exposure leads to smell fatigue.
• Environmental conditions can alter odor perception.
• Habituation affects the ability to distinguish odors.
• Brain focuses on differences and changes in odors.

Genetic Components of Olfactory Perception:

• Thousands of olfactory receptor gene sequences are known.
• Olfactory receptors are seven-helix-turn transmembrane proteins.
• Metal-ion binding sites in receptors help detect odorants.
• Copper is essential for detecting certain sulfur-containing compounds.
• Genetic component plays a crucial role in odor perception.

Odor Measurement, Sources, Effects, and Control:

• Measuring Techniques: Sensory evaluation, Chemical analysis, Electronic noses, Odor meters, Gas chromatography.
• Concentration: Odor pervasiveness, Measurement of odor sensation, Dilution process, Odor threshold, Odor intensity.
• Sources of Odor: Natural sources, Human activities, Industrial processes, Agricultural practices, Waste management.
• Effects of Odor: Health impacts, Environmental effects, Social implications, Psychological effects, Economic consequences.
• Odor Control: Odor elimination, Odor masking, Odor neutralization, Air purification, Regulatory measures.

Odor Data Sources