Life Cycle
Porphyra displays a heteromorphic alternation of generations. The thallus we see is the haploid generation; it can reproduce asexually by forming spores which grow to replicate the original thallus. It can also reproduce sexually. Both male and female gametes are formed on the one thallus. The female gametes while still on the thallus are fertilized by the released male gametes, which are non-motile. The fertilized, now diploid, carposporangia after mitosis produce spores (carpospores) which settle, then bore into shells, germinate and form a filamentous stage. This stage was originally thought to be a different species of alga, and was referred to as Conchocelis rosea. That Conchocelis was the diploid stage of Porphyra was discovered by the British phycologist Kathleen Mary Drew-Baker in 1949 for the European species Porphyra umbilicalis. It was later shown for species from other regions as well.
Read more about this topic: Porphyra
Famous quotes containing the words life and/or cycle:
“Jupiter, not wanting man’s life to be wholly gloomy and grim, has bestowed far more passion than reason—you could reckon the ration as twenty-four to one. Moreover, he confined reason to a cramped corner of the head and left all the rest of the body to the passions.”
—Desiderius Erasmus (c. 1466–1536)
“Oh, life is a glorious cycle of song,
A medley of extemporanea;
And love is a thing that can never go wrong;
And I am Marie of Roumania.”
—Dorothy Parker (1893–1967)