Short Answer TypeA hill station city had abundance of different species of lichens a few years back. Since it has turned a busy tourist spot very few lichens are found there.
(a)What could be the possible reason for this?
(b) What measures are to be taken to conserve lichens?
Long Answer TypeBriefly, explain the pattern of lifecycle followed by
a. All bryophytes
b. All pteridophytes
With the help of a schematic diagram describe the haplo-diptontic life cycle pattern in plants
One Word AnswersThe plant body in higher plants is well differentiated and well developed. Roots are the organs used for the purpose of absorption. What is the equivalent of roots in the less developed lower plants?
Short Answer TypeHeterospory i.e., formation of two types of spores – microspores and megaspores is a characteristic feature in the life cycle of a few members of pteridophytes and all spermatophytes. Do you think heterospory has some evolutionary significance in plant kingdom?
Heterospory involves the formation of two types of spores. Microspores and megaspores. The smaller ones are microspores and the larger ones are megaspores. In the pteridophytes, the microspores and the megaspores germinate to give rise to male and female gametophytes respectively.
From the evolutionary point of view , heterospory is a precursor to the seed habit found in higher plants. Seeds enable the plants to survive in the unfavourable conditions. seeds also help in the dispersal of the plant species over a wider geographical area.
Each plant or group of plants has some phylogenetic significance in relation to evolution : Cycas, one of the few living members of gymnosperms is called as the ‘relic of past’. Can you establish a phylogenetic relationship of Cycas with any other group of plants that
justifies the above statement?
In which plant will you look for mycorrhiza and coralloid roots? Also, explain what these terms mean.
Long Answer TypeLichen is usually cited as an example of ‘symbiosis’ in plants where an algal and a fungal species live together for their mutual benefit. Which of the following will happen if algal and fungal partners are separated from
each other?
a. Both will survive and grow normally and independent from each other.
b. Both will die
c. Algal component will survive while the fungal component will die.
d. Fungal component will survive while algal partner will die.
Switch
