The pigments in Porphyra are as follows:
Chlorophyll a is used for photosynthesis, and the green color is sometimes masked by phycoerythrin, which contributes the "red" to the red algae. Many of the red algae do not have a reddish-color as a result of photodestruction of phycoerythrin. Phycocyanin generally reflects a bluish color. The phycobilins are located in phycobilisomes, which can be found on the outer surfaces of thylakoids.
The primary storage form for Porphyra is by starch.
The cell wall of Porphyra is remarkable in many ways. The outermost cuticle is made of protein, with an outer amorphous compartment made of mucilage or slime. Inside is a rigid compartment made of microfibrils. There has been mannan found in some species of Porphyra.
Porphyra has the remarkable capacity for survival against dessication and can dry out for days without harm. This is a result of the cell wall. The ability to withstand dessication is also useful for transmitting spores once the thallus is remoistened.
© 1999 Lisa Chen. All rights reserved. Use for educational purposes permitted with acknowledgment and notice.