What does macrospore mean?
A macrospore is the large reproductive spore formed by heterosporous plants, including seed plants and certain ferns and lycophytes. After meiosis, it develops into a female gametophyte, the structure that produces and contains the egg cells. In flowering plants, the macrospore develops within an ovule, normally divides to form the embryo sac, and ultimately participates in the production of the embryo. Its counterpart is the microspore, a smaller spore that develops into a male gametophyte and produces sperm. The distinction reflects the plant’s division of labor between female and male reproductive functions, although the terms technically emphasize spore size as well as sex. Macrospores are also known as megaspores. In seed development, a surviving functional macrospore and the tissues surrounding it form the structure from which the ovule develops into a seed.
nounA large spore produced by heterosporous plants, which develops into a female gametophyte and contains the plant's female reproductive cells. It contrasts with the smaller microspore, which develops into a male gametophyte.
- The larger of the two kinds of spore produced by a heterosporous plant, which develops into a female gametophyte.
"The macrospore develops within the ovule and ultimately gives rise to the embryo sac."
"The ovule contains a single macrospore that develops into the female gametophyte."
"Researchers used microscopy to determine whether the developing macrospore had divided normally."
The plural is macrospores.
"Several macrospores were visible in the developing ovule."
Every seed begins with a botanical paradox: a single large cell, the macrospore, carries the plant's female future.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of macrospore
The word combines the combining form macro-, derived from Greek makros meaning “long” or “large,” with spore, from Greek spora meaning “seed” or “sowing.” The compound macrospore developed in botanical terminology to distinguish the larger spore from the microspore. It is also called a megaspore, using the synonymous combining form mega-, from Greek megas meaning “great” or “large.”
Related word forms
How macrospore is actually used
This is a technical botanical term. It is also called a megaspore, especially in classifications that emphasize its reproductive role.
Easily confused with macrospore
A macrospore is the larger, female-producing spore, whereas a microspore is the smaller, male-producing spore.