Archaeplastida

Definition

Archaeplastida is a major group of eukaryotes that includes land plants, green algae, red algae, and glaucophytes. These organisms are united by their possession of plastids that originated from primary endosymbiosis with a cyanobacterium.

5 Must Know Facts For Your Next Test

1. Archaeplastida members have plastids derived from primary endosymbiosis with cyanobacteria.
2. This group includes three main lineages: Glaucophyta, Rhodophyta (red algae), and Chloroplastida (green algae and land plants).
3. Green algae within Archaeplastida share a common ancestor with land plants, making them crucial for understanding plant evolution.
4. Red algae are primarily marine organisms and have unique pigments like phycoerythrin which give them their distinctive color.
5. Glaucophytes are rare freshwater algae that retain peptidoglycan between the two membranes of their chloroplasts.

Review Questions

Related terms

Plastids: Organelles found in plant cells and other eukaryotic organisms involved in photosynthesis, storage, and synthesis.

Endosymbiosis:

A symbiotic relationship where one organism lives inside another; key to the origin of mitochondria and chloroplasts.

Phycoerythrin:

A red pigment found in red algae that assists in capturing light for photosynthesis.