Physiology and Sensation Practice Flashcards

A collection of vocabulary flashcards covering basic physiology, nervous system divisions, receptor mechanics, and the gustatory system based on the lecture transcript.

Physiology

Study of the normal functions of living organisms and their anatomy

Sensation

Conscious or subconscious awareness of external or internal stimuli

Receptors

Sensory nerve terminals or specialized structures that receive stimuli and relay them to the central nervous system (CNS)

Central Nervous System (CNS)

The part of the nervous system responsible for sensory activities, memory, and emotions, composed of the brain and spinal cord

Peripheral Nervous System (PNS)

A division of the nervous system consisting of the Autonomic Nervous System (ANS) and Somatic Nervous System (SNS)

Autonomic Nervous System (ANS)

A component of the PNS responsible for involuntary functions and movements

Sympathetic Division

The part of the Autonomic Nervous System responsible for the fight-or-flight response

Parasympathetic Division

The part of the Autonomic Nervous System responsible for rest-and-relax activities

Enteric Division

The part of the Autonomic Nervous System responsible for the digestive system

Somatic Nervous System (SNS)

The part of the nervous system responsible for voluntary movements

Active sites

Specific binding sites on receptors that recognize and bind to ligands

Ligands

Signaling molecules that bind to receptors

Transducer

Any device or structure that converts one form of energy into another

Transduction

A process in which a stimulus or ligand-receptor interaction produces a change in the receptor, initiating a cellular response

Sensory Transducers

Structures that convert stimulus energy into electrochemical energy (action potential)

Action Potential

A pattern of electrochemical energy resulting from a converted stimulus

RMP (Resting Membrane Potential)

The resting state of a membrane potential, which is about $-70\,mV$

Threshold Level

The membrane potential needed to trigger an action potential

Depolarization

The phase of an action potential in which $Na^+$ channels open

Repolarization

The phase of an action potential in which $Na^+$ channels close and $K^+$ channels open

Hyperpolarization

The state where $K^+$ channels remain open after the RMP is reached

Receptor Potential

A type of local potential involving graded voltage changes across the plasma membrane of a receptor cell

Myelin Sheath

A fatty layer that acts as an insulator for electrical impulses

Saltatory Conduction

The jumping of an electrical impulse from one node of Ranvier to another

Gustation

The sense of taste, which assesses whether ingested substances are nutritious or hazardous

Gustatory Receptors

Specialized chemoreceptors, or modified epithelial cells, that detect tastants in food

Papillae

Raised bumps on the surface of the tongue lined by stratified squamous epithelium that contain taste buds

Circumvallate Papillae

Papillae located in the posterior region of the tongue that are sensitive to bitter flavors

Foliate Papillae

Papillae located on the posterolateral borders of the tongue sensitive to sour and salty flavors

Fungiform Papillae

Papillae concentrated at the tip and lateral margins of the anterior two-thirds of the tongue, sensitive to sweet and savory flavors

Filiform Papillae

The most numerous type of papillae located on the dorsal surface of the anterior 2/3 of the tongue; they lack taste buds and sense touch

Taste Bud

A structure containing several specialized gustatory receptor cells, taste hairs, and associated supporting and basal cells

Taste Pore

An opening at the surface of the epithelium associated with the taste bud

Taste Hair

A structure within a taste bud that extends toward the taste pore

Umami

One of the five basic taste sensations, associated with amino acids like those in meat broth and aged cheese

Tastants

Binding molecules that stimulate gustatory receptors

Odorants

Binding molecules that stimulate olfactory receptors

Olfactory Receptors

Dendrites of true neurons located in the olfactory epithelium of the nasal cavity that detect various smells