pinocytosis

Học thuật

Thân thiện

A cell undergoes pinocytosis to absorb nutrients from its environment.

Definition

Noun:
- A cellular process of ingestion: Pinocytosis is a specific biological mechanism where a living cell actively takes in ("engulfs") tiny droplets of fluid from its external environment. The cell membrane folds inward to form a small vesicle that encloses the fluid, which is then brought into the cell's interior for incorporation and use.

Usage

Pinocytosis is a fundamental process for cellular nutrition and signaling. It is a form of endocytosis, specifically for liquids, distinct from phagocytosis, which is for solid particles.
This term is used almost exclusively in scientific contexts, particularly in cell biology, physiology, and medicine.

Examples

Noun:
- Nutrient absorption in the small intestine involves pinocytosis by the epithelial cells lining the gut.
- The researcher studied how certain hormones stimulate pinocytosis in target cells.

Advanced Usage

"Constitutive pinocytosis": Refers to the continuous, non-selective form of fluid uptake that occurs in many cell types as a baseline activity.
- Macrophages exhibit high rates of constitutive pinocytosis.
"Receptor-mediated pinocytosis": A selective form where specific molecules in the fluid bind to receptors on the cell membrane, triggering the engulfing process more efficiently.
- Cholesterol enters cells via receptor-mediated pinocytosis.

Variants and Related Words

Pinocytotic (adj): Relating to or characterized by pinocytosis.
- The pinocytotic vesicles were visible under the electron microscope.
Pinocytose (v): (Less common) To engage in or undergo pinocytosis.
- Certain white blood cells can pinocytose surrounding fluid.

Synonyms

Fluid-phase endocytosis: A more descriptive technical synonym.
Cell drinking: An informal, illustrative term comparing the process to a cell "drinking" its environment.

Related Concepts (Not Phrasal Verbs or Idioms)

Endocytosis: The broader category of cellular uptake processes that includes pinocytosis.
Phagocytosis: ("Cell eating") The engulfment of solid particles.
Exocytosis: The reverse process, where a cell expels material.

A cell undergoes pinocytosis to absorb nutrients from its environment.

Noun