Plant Kingdom – Solutions
1. What is the basis for the classification of algae?
Initially, algae classification was based on a single visible character in the form of the colour of the thallus. Accordingly, three main algal divisions were recognised – Green algae, Brown algae and Red algae. However, at present, in addition to the colour, some more characteristics are taken into consideration for algal division. Some of them are:
a. Type of photosynthetic pigments present
b. Nature of the stored food
c. Composition of the cell wall
d. Number and position of the flagella
Based on the above features, algae have been classified into three main classes – Chlorophyceae (green alga), Phaeophyceae (brown alga) and Rhodophyceae (red alga).
2.When and where does reduction division take place in the life cycle of a
liverwort, a moss, a fern, a gymnosperm and an angiosperm?
Reduction division is a meiotic cell division, and it occurs in the reproductive organs at different stages of the life cycle.