The number of chromosomes in a gamete of Ophioglossum is:
1. | 1260 | 2. | 380 |
3. | 630 | 4. | 78 |
Corresponding to ‘monoecious’ in a plant, the bisexual condition in a fungus would be best described as:
1. | Homothallic | 2. | Heterothallic |
3. | Hermaphrodite | 4. | Complete ad perfect |
A major disadvantage of external fertilization is:
1. | Lack of variations amongst the offspring |
2. | Need for the production of a significant number of male gametes |
3. | A high threat to the progeny for survival up to adulthood |
4. | The number of progeny per reproductive event will mostly be one |
In animals exhibiting external fertilization:
1. | the offspring are less prone to predation |
2. | the reproduction is independent of water |
3. | there is synchrony between sexes for the release of gametes |
4. | the number of female gametes are highly reduced |
Consider the given statements:
I. | Gemmules are asexual reproductive structures in sponges. |
II. | In Bryophyllum, vegetative propagation takes place by leaf buds. |
III. | Marchantia is monoecious and Chara is dioecious. |
The correct statements are:
1. | Only I and II | 2. | Only I and III |
3. | Only II and III | 4. | I, II, and III |
Organisms relying completely on external fertilization are almost always likely to be found in:
1. Tropical forests
2. Moist environments
3. Aquatic habitats
4. Dry, arid conditions
In the given diagrams each part A, B, C and D shows a reproductive structure in an organism marked as ‘X’. Select the option where all parts are correctly matched:
A. |
|
B. | |
B. |
D. |
1. | A: Oogonium of Chara; B: Archegoniophore of Marchantia; C: Conidia of Penicillium; D: Offset of Eicchornia |
2. | A: Antheridium of Chara; B: Antheridiophore of Marchantia; C: Sporangiophores of Penicillium; D: Offset of Eicchornia |
3. | A: Oogonium of Chara; B: Antheridiophore of Marchantia; C: Conidia of Penicillium; D: Offset of Eicchornia |
4. | A: Antheridium of Chara; B: Archegoniophore of Marchantia; C: Conidia of Penicillium; D: Stolon of Eicchornia |
In animals exhibiting internal fertilization:
1. | the number of sperms produced is significantly reduced |
2. | a large number of offspring are produced per reproductive event |
3. | offspring are extremely vulnerable to predators |
4. | the chance of individual egg fertilization is high |
Consider the following statements:
I: | Meiosis never occurs in organisms that are haploid |
II: | Gametes are haploid and the parent plant body from which they arise must be diploid |
1. Only I is correct
2. Only II is correct
3. Both I and II are incorrect
4. Both I and II are correct
Identify the incorrectly matched pair:
1. Cockroach - Unisexual animal
2. Chara - Monoecious plant
3. Marchantia - Dioecious plant
4. Sweet potato - Unisexual flower