Final answer:
The key morphological characteristics of the SAR clade include alveoli, pseudopodia, flagella, and plastids.
Step-by-step explanation:
The key morphological characteristics of the SAR clade include:
- Alveoli: Many organisms in the SAR clade have alveoli, sac-like structures that are involved in gas exchange.
- Pseudopodia: Some members of the SAR clade, such as amoebas, have pseudopodia, which are temporary extensions of the cell membrane used for movement and capturing food.
- Flagella: Many SAR clade organisms have flagella, whip-like structures that help with movement.
- Plastids: Some members of the SAR clade have plastids, which are organelles involved in photosynthesis.