positive chemotaxis
Học thuậtThân thiện
Definition
Noun: * Movement toward a chemical stimulus: A biological process in which a cell or organism moves directly toward a higher concentration of a specific chemical substance. This is a form of taxis, a directional movement in response to an external cue.
Usage
This term is used primarily in scientific contexts, specifically in biology, microbiology, and immunology, to describe the directed movement of motile cells or organisms.
Examples
- The positive chemotaxis of sperm cells toward the egg is crucial for fertilization.
- Researchers observed positive chemotaxis in bacteria moving toward a nutrient source.
- White blood cells exhibit positive chemotaxis toward chemicals released by infected tissues.
Advanced Usage
- The term is often used in contrast to , which is movement from a chemical stimulus.
- It can be described quantitatively in experiments, e.g., "The strength of the positive chemotaxis was measured using a capillary assay."
Variants and Related Words
- Chemotaxis (n): The broader phenomenon of movement in response to a chemical gradient, encompassing both positive and negative responses.
- Chemotactic (adj): Relating to or involving chemotaxis. (e.g., a chemotactic response).
- Negative Chemotaxis (n): Movement away from a chemical stimulus.
Synonyms
- Attractant-based movement
- Chemoattraction (Note: This is a closely related concept, often implying the action of the attractant rather than the movement itself.)
Antonyms
- Negative chemotaxis
- Repellent-based movement
Noun
- movement toward a chemical stimulus