15.2. Plant Development Flashcards
Plant development starts with a zygote…
The zygote divides asymmetrically to produce an apical daughter and basal daughter cell.
The apical daughter forms the embryo and the mature plant; the basal daughter forms the suspensor (an extra-embryonic support structure).
Plant development involves three tissue layers…
Dermal: outside the developing plant:
- Covers and protects the plant.
- Controls gas exchange and water absorption.
Ground: intermediate layer:
- Provides structural support.
- Carries out photosynthesis.
- Stores water and nutrients.
Vascular: in the middle of the plant:
- Transports water, mineral ions and sugars to different parts of the plant.
There are also two meristem regions, containing undifferentiated cells that will continue to give rise to new tissues and orchestrate growth throughout life.
Shaping plant tissues…
Cell migration doesn’t play a role because plants have rigid cell walls that restrict their movement.
Instead, plant tissues are shaped and grow due to a combination of cell division, followed by cell elongation.
Meristem regions that contain stem cells divide and then elongate (in which cells gradually become longer) to drive continuous plant growth and shaping of plant tissues.
