Conifers are adapted to tolerate extreme environmental conditions because of?
1. broad hardy leaves
2. superficial stomata
3. thick cuticle
4. the presence of vessels
Which one of the following statements is wrong?
1. | Algae increase the level of dissolved oxygen in the immediate environment |
2. | Algin is obtained from red algae and carrageenan from brown algae |
3. | Agar-agar is obtained from Gelidium and Gracilaria |
4. | Laminaria and Sargassum are used as food |
Which of the following statement is correct?
1. | Ovules are not enclosed by the ovary wall in gymnosperms. |
2. | Selaginella is heterosporous, while Salvinia is homosporous. |
3. | Horsetails are gymnosperms. |
4. | Stems are usually unbranched in both Cycas and Cedrus. |
An example of colonial alga is:
1. | Volvox | 2. | Ulothrix |
3. | Spirogyra | 4. | Chlorella |
Select the mismatch
1. Cycas - Dioecious
2. Salvinia - Heterosporous
3. Equisetum - Homosporous
4. Pinus - Dioecious
In bryophytes and pteridophytes, transport of male gametes requires?
1. | insects | 2. | birds |
3. | water | 4. | wind |
1. | Salvinia, Ginkgo and Pinus all are gymnosperms |
2. | Sequoia is one of the tallest trees |
3. | The leave of gymnosperms are not well adapted to extremes of climate |
4. | Gymnosperms are both homosporous and heterosporous |
Read the following five statements (I to V) and select the option with all correct statements.
I: | Mosses and lichens are the first organisms to colonise bare rock. |
II: | Selaginella is a homosporous pteridophyte. |
III: | Coralloid roots in Cycas have VAM. |
IV: | Main plant body in bryophytes is gametophytic, whereas in pteridophytes it is sporophytic. |
V: | In gymnosperms, male and female gametophytes are present within sporangia located on sporophytes. |
1. | I, III and IV | 2. | II, III and IV |
3. | I, IV and V | 4. | II, III and V |
Which one of the following statements is wrong?
1. Algin and carrageenan are products of algae
2. Agar-agar is obtained from Gelidium and Gracilaria
3. Chlorella and Spirulina are used as space food
4. Mannitol is stored food in Rhodophyceae