Anatomy and Physiology for Clinical Aromatherapy Flashcards

Which route of essential oil administration allows for direct absorption into the bloodstream via the alveoli in the lungs?

Answer: Inhalation

Inhaled essential oil molecules reach the alveoli, where they pass directly into the bloodstream through the thin alveolar walls during gas exchange.

The olfactory nerve (cranial nerve I) transmits aromatic signals from the nasal epithelium directly to which brain structure?

Answer: Olfactory bulb

Olfactory receptor neurons send signals via cranial nerve I to the olfactory bulb, the first relay station in the brain for smell, which then connects directly to the limbic system.

Which layer of the skin serves as the primary barrier that essential oil molecules must cross for topical absorption to occur?

Answer: Stratum corneum

The stratum corneum is the outermost, keratinized layer of the epidermis and serves as the principal barrier to transdermal penetration of applied essential oil molecules.

In clinical aromatherapy, the lymphatic system is most relevant to which aspect of essential oil absorption?

Answer: Transportation of fat-soluble essential oil components from the digestive tract via lacteals

When essential oils are taken orally, fat-soluble constituents are absorbed from the GI tract through lacteals (lymphatic capillaries) in the intestinal villi before entering general circulation.

Inhalation of essential oils stimulates which brain system FIRST through the olfactory pathway, explaining immediate emotional and memory responses?

Answer: Limbic system including the amygdala and hippocampus

Olfactory signals project directly to the limbic system—bypassing the thalamus—reaching the amygdala and hippocampus, which explains the immediate emotional and memory-linked reactions to aromas.

The hepatic first-pass effect is most clinically significant for which route of essential oil administration?

Answer: Oral ingestion of essential oils

Oral ingestion routes essential oil components through portal circulation to the liver before systemic distribution, subjecting them to first-pass metabolism that significantly reduces bioavailability.

Which specialized cells in the nasal olfactory epithelium detect aromatic molecules and generate the initial electrical signal for smell?

Answer: Olfactory receptor neurons

Olfactory receptor neurons are bipolar sensory neurons whose cilia contain G-protein-coupled odorant receptors that bind aromatic molecules and convert the chemical stimulus into an electrical signal.