noun
- Plural of proplastid; small, undifferentiated plastid precursors found in plant cells that develop into mature chloroplasts or other plastids.
Usage: biology; botany; technical term
Examples
- Proplastids in young plant cells gradually differentiate into functional chloroplasts.
- The development of proplastids into mature plastids is essential for photosynthesis.
- Scientists observed proplastids under the electron microscope to study plastid biogenesis.
- In etiolated seedlings, proplastids remain underdeveloped until exposed to light.
- The transformation of proplastids into chloroplasts requires specific light signals and gene expression.