Which of the following is the most critical event of sexual reproduction?
1. | Gametogenesis | 2. | Gamete Transfer |
3. | Fertilization | 4. | Embryogenesis |
A plant with both male flowers and female flowers is called as:
1. | Unisexual | 2. | Bisexual |
3. | Dioecious | 4. | Monoecious |
A flower that produces only pollens is called as:
1. | Perfect flower | 2. | Staminode |
3. | Dioecious | 4. | Staminate |
Identify the incorrectly matched pair:
1. Cockroach - Unisexual animal
2. Chara - Monoecious plant
3. Marchantia - Dioecious plant
4. Sweet potato - Unisexual flower
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:
|
Organism |
Chromosome number in a meiocyte |
1. |
Ophioglossum |
630 |
2. |
Housefly |
12 |
3. |
Maize |
20 |
4. |
Butterfly |
380 |
In several simple plants like algae, bryophytes, and pteridophytes, water is the medium through which gamete transfer takes place. To increase the chances of fertilization, such plants:
1. | Produce a large number of female gametes that are non-motile |
2. | Produce a large number of male gametes that is several thousand times the number of female gametes produced |
3. | Produce a large number of female gametes that is several thousand times the number of male gametes produced |
4. | Do not have the capability of reproducing asexually |
A reproductive strategy that involves the development of a female (rarely a male) gamete (sex cell) without fertilization is called:
1. | Parthenogenesis | 2. | Parthenocarpy |
3. | Panmixis | 4. | Amphimixis |
Consider the two statements:
I: | Organisms exhibiting external fertilisation show great synchrony between the sexes. |
II: | Such organisms release a large number of gametes into the surrounding medium (water). |
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 correct but II is incorrect. |
4. | Both I and II are incorrect. |
A major disadvantage of external fertilization is:
1. | Lack of variation in the progeny |
2. | The number of progeny produced can only be one or few |
3. | The offspring are extremely vulnerable to predators threatening their survival up to adulthood |
4. | The progeny have a very short life span and a low reproductive potential |