Question
Question: What is incorrect for brown algae A) Presence of chlorophyll a and chlorophyll c B) Occurrence o...
What is incorrect for brown algae
A) Presence of chlorophyll a and chlorophyll c
B) Occurrence of fucoxanthin
C) Presence of chlorophyll a and chlorophyll b
D) Attachment of substratum
Solution
Algae are largely aquatic either freshwater or marine organisms. Some members of algae occur with association with fungi and animals. Algae are unicellular and colonial or filamentous or thalloid. Algae are covered over by mucilage, which protects them from epiphytic growth and decaying effect of water.
Complete answer:
Brown algae are the members of phaeophyceae. They are found in marine habitat.they show great variation in size and form. The plant body is usually attached to the substratum by a holdfast and has a stalk the stipe and leaf like photosynthetic organ called frond. They possess chlorophyll a and chlorophyll c, carotenoids and xanthophylls pigment called fucoxanthin. The brown colour of the algae is due to the presence of large amounts of xanthophylls pigments.their cells have a cellulosic wall usually covered on the outside by a gelatinous coating of algin.
Additional information:
Reproduction in brown algae:
Vegetative reproduction takes place by fragmentation.
Asexual reproduction is by biflagellate zoospore that are pear shaped and have two unequal laterally attached flagella
Sexual reproduction may be isogamous, anisogamous, and oogamous. In isogamy and anisogamy both the gametes are motile or flagellated . The female gametes are nonmotile . The union of gametes take place in water or within the oogonium. The gametes are pyriform and bear two laterally attached flagella.For example: ectocarpus, dictyota,focus, sargassum
Hence the correct answer is option ‘A’.
Note: Agar is an algae which is used in preparation of jellies and icecreams. It is obtained from gelidium and gracilaria. Carrageenan is used as an emulsifier in chocolates,paints and toothpaste. Many marine algae are rich sources of protein.