Explain the types of Algal divisions.

1. Chlorophyta (green algae)
- Have chloroplasts containing chlorophyll a & b (are predominant) carotenoids and xanthophylls
- Reserve food material is starch found in association with pyrenoids
- Have flagella equal in length and apically inserted
- Have cellulose cell wall
- Cells are eukaryotic
- Majority are aquatic
- Thallus structure may be unicellular motile forms e.g chlamydmonas, colonial form e.g volvox, filamentous branched

2. Rhodophyta (Red algae)
1. Contain chlorophyll a and d and accessory pigments called phycobilins
2. Cell wall is made of cellulose, hemi-cellulose and sulphated polysaccharides
3. Storage product / food is floridean – compounds of sugars and gylcerols
4. Have no flagella
5. Their lifecycles involve both sexual and asexual forms
6. Are maturity marine, mostly sea weeds

3. Bacillariophyta (Diatoms)
1. Contain chlorophyll a and c and the pigment fucoxanthin
2. Cell wall is made of silica and pectin (pectin is elastic)
3. Storage product are Carbohydrates and oils
4. Lack flagella
5. They are mainly marine forming a major component of phytoplanktons and also occur in soil

4. Pyrrophyta (Dinoflagellates/ fire algae)
1. Contain chlorophyll a & c and brown pigment called peridinin (peridinin) gives the group green brown or orange brown colour
2. Have 2 unequal flagella which provide forward movement and act as sensory organs
3. Most species are unicellular, few are colonial and few filamentous
4. Have cellulose cell wall
5. Food reserve or storage product is true starch
6. Are mainly marine forming a major component of phytoplanktons
• Cause red tides – Toxic
• Form bioluminescent and contribute to glow of water

5. Phaeophyta (Brown Algae)
1. Contain chlorophyll a and c and a pigment fuconxanthin which gives them a characteristic brown colour
2. Are filamentous with complex differentiation in anatomy and morphology than any other algae – with no unicellular forms
3. Store Carbohydrates in form of mannitol and laminaran (oil)
4. Cell wall is made of cellulose, hemi-cellulose and pectin
5. Are mainly marine

6. Xanthophyta (Yellow green algae)
1. Contain chlorophyll a + c other photosynthetic pigment are heteroxanthin diadenoxantin & B-carotene
2. Cell wall is made of pectin compounds a few have cellulose
3. Store food in form of oil (chrysolaminaran)
4. Plant cell may be cellular or multicellular having more than one chromatophone per cell
5. Produce gametes that are unequally biflagellated
6. Majority are fresh water but few are marine

7. Chrysophyta (golden brown algae)
- Have chlorophyll a +c other pigments are xanthophylls and B carotenes (predominant over chlorophylls)
- Food reserve is chrysolaminaran (oil)
- Are flagellated and the flagella is a key tool in their classification. Some are equally biflagellate, others unequally biflagellate others are uniflagellate.

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Kavungya answered the question on March 13, 2019 at 05:29