polar body
Học thuậtThân thiện
Definition
- Noun:
- A small cell containing little cytoplasm that is produced along with the oocyte and later discarded: A "polar body" is a small, non-functional haploid cell that is generated as a byproduct during the meiotic divisions of an oocyte (egg cell) in female animals. Its primary role is to discard excess genetic material, allowing the oocyte to retain most of the cytoplasm and nutrients necessary for development.
Usage Examples
- Noun:
- The first polar body is extruded during the first meiotic division.
- The polar body eventually degenerates and is reabsorbed.
- Scientists can sometimes perform genetic testing on a polar body to infer the genetic makeup of the corresponding oocyte.
Advanced Usage
- "polar body biopsy": a technique used in assisted reproductive technology where a polar body is removed and analyzed for genetic abnormalities before fertilization.
- Polar body biopsy can provide information about the genetic health of the egg.
Variants and Related Words
- Oocyte (n): The developing egg cell that produces the polar bodies.
- Meiosis (n): The type of cell division that results in the formation of polar bodies and the haploid oocyte.
- Haploid (adj): Having a single set of chromosomes, a characteristic of both the mature oocyte and the polar bodies.
Synonyms
- None commonly used: "Polar body" is a specific biological term with no direct common synonym. Descriptive phrases like "meiotic byproduct cell" or "discarded haploid cell" may convey a similar idea in explanatory contexts.
Related Phrases
- First polar body: The polar body produced after the first meiotic division.
- Second polar body: The polar body produced after the second meiotic division, following fertilization.
Notes
- The term is almost exclusively used in the context of developmental biology, embryology, and reproductive medicine.
Noun
- a small cell containing little cytoplasm that is produced along with the oocyte and later discarded