Phaeophyceae Flashcards
What is the primary habitat of Phaeophyceae?
Marine habitats
Phaeophyceae, or brown algae, predominantly thrive in marine environments.
What is the range of forms observed in Phaeophyceae?
From simple branched forms to profusely branched forms
Examples include Ectocarpus (simple) and kelps (complex).
What is the maximum height that kelps can reach?
100 metres
Kelp is one of the largest forms of brown algae.
Which pigments are present in Phaeophyceae?
Chlorophyll a, c, carotenoids, and xanthophylls
These pigments contribute to the color variation in brown algae.
What determines the color variation in Phaeophyceae?
The amount of xanthophyll pigment
Color can range from green to various shades of brown.
What form do Phaeophyceae store their food?
As complex carbohydrates, laminarin or mannitol
These storage forms are crucial for energy metabolism.
What type of wall do vegetative cells of Phaeophyceae possess?
Cellulosic wall
Typically covered by a gelatinous coating of algin.
What structures are involved in the attachment of Phaeophyceae to the substratum?
Holdfast, stipe, and frond
The holdfast anchors the algae, while the stipe supports the frond.
How does vegetative reproduction occur in Phaeophyceae?
By fragmentation
This allows for the propagation of the algae without sexual reproduction.
What type of reproduction do most brown algae utilize?
Asexual reproduction by biflagellate zoospores
These zoospores are pear-shaped with two unequal flagella.
What are the types of sexual reproduction found in Phaeophyceae?
Isogamous, anisogamous, or oogamous
The type of reproduction can vary among different species.
Where does the union of gametes occur in oogamous species?
In water or within the oogonium
This reproductive strategy is crucial for the fertilization process.
What shape are the gametes of Phaeophyceae?
Pyriform (pear-shaped)
Gametes bear two laterally attached flagella.
Name some common forms of Phaeophyceae.
Ectocarpus, Dictyota, Laminaria, Sargassum, Fucus
These are representative genera within the brown algae group.
