The structure in phanerogams that is homologous to the megasporangium of cryptogams is known as:
1. Embryo sac
2. Pollen sac
3. Nucellus of the ovule
4. Carpel
Sphagnum can be distinguished from mosses by all the following characteristics except:
1. The stem has no rhizoids
2. Leaves have green and hyaline cells
3. The sex organs do not limit the indefinite growth of the main axis
4. The capsule is borne on seta
Aplanogametes [gametes that do not have flagella] are the special features of:
1. Spirogyra and Zygnema
2. Spirogyra and Vaucheria
3. Ulothrix and Zygnema
4. Chlamydomanas and Ulothrix
Match each item in column I with one in Column II and select the correct answer from the codes given below:
Green alga |
Feature |
A. Chlamydomanas |
a. Non motile colony |
B. Volvox |
b. Coenobium with two kinds of cells |
C. Hydrodictyon |
c. Palmella stage |
D. Spirogyra |
d. Spiral chloroplasts |
Codes:
A | B | C | D | |
1. | a | d | b | c |
2. | a | b | c | d |
3. | c | b | a | d |
4. | c | d | a | b |
Consider the given two statements:
I. The term ‘archegonium’ is not used for megagametophytes, angiosperms and gnetophytes.
II. The sperms are delivered by means of a pollen tube in these plants.
1. Both I and II are correct and II explains I
2. Both I and II are correct but II does not explain I
3. I is true but II is false
4. Both I and II are false
Consider the given two statements:
I. Formation of a multicellular haploid gametophyte as in ferns rather than limiting it to a few cells is believed to provide an evolutionary advantage.
II. The transmission of harmful traits is less likely to occur to the future generations.
1. Both I and II are correct and II explains I
2. Both I and II are correct but II does not explain I
3. I is true but II is false
4. Both I and II are false
In contrast to conifers, gnetophytes produce:
1. Simple pollen strobili and simple seed strobili
2. Simple pollen strobili and compound seed strobili
3. Compound pollen strobili and simple seed strobili
4. Compound pollen strobili and compound seed strobili
Rather than having true roots, stems and leaves the members of Phaeophyceae have root like holdfast, stem like stipe and leaf like fronds. What will be true for these structures?
I. Holdfasts are not the primary organs for water and nutrient uptake.
II. In brown algae like Fucus, the tissues in stipe include a central pith, a surrounding cortex and an outer epidermis.
III. Gas filled floats called pnematocysts provide buoyancy in many brown algae.
1. I and II only
2. I and III only
3. II and III only
4. I, II and III
The term ‘seaweeds’ is used to describe several macroscopic, multicellular marine algal species belonging to:
I. Chlorophyceae
II. Phaeophyceae
III. Rhodophyceae
1. | I and II only | 2. | I and III only |
3. | II and III only | 4. | I, II and III |
What would be true for the structure labeled with letter ‘X’ in the given diagram showing the ultrastructure of Chlamydomanas?
1. It is the region of the chloroplast where circular DNA is present
2. It is associated with the operation of a carbon-concentrating mechanism (CCM)
3. It is the inclusion body with accumulated toxic wastes for elimination
4. It is filled with air and is responsible for buoyancy of the organism