Xenogamy

Q.

Mention two strategies evolved to prevent self-pollination in flowers.

Q.

What is self-incompatibility? Why does self-pollination not lead to seed formation in self-incompatible species?

Q.

What is pollen viability?

Q.

What are the advantages of inbreeding?

Q.

Mention two strategies evolved to prevent self-pollination in flowers.

Q.

What is the difference between autogamy and geitonogamy?

Q. Which of the following will not decrease inbreeding depression?

1. Producing unisexual flowers.
2. Cross-pollination.
3. Anther and stigma growing up to same height in a bisexual flower.
4. Unsynchronised pollen release and stigma receptivity.

Q.

Is pollen haploid or diploid?

Q. Hisardale is obtained by

1. Mating of superior males and females of the same breed having no common ancestors.
2. Mating of two different closely related species.
3. Mating of superior males and females of the same breed having common ancestors.
4. Mating of superior males and females of different breeds

Q. A pollen lands from anther to stigma of a flower, however there is no pollen tube formation. What is the reason behind this?

1. No synchrony between pollen release and stigma receptivity
2. Pollen is no longer viable
3. Self-incompatibility
4. Any of the above

Q. In which of the following types of pollination, genetically different pollen grains are brought to the stigma?

1. Geitonogamy
2. Autogamy
3. Xenogamy
4. All of the above

Q. Self-incompatibility prevents pollen tube formation by pollen grains on the stigma of the__________.

1. same flower
2. none of the above
3. other flowers of the same plant
4. both a and b

Q.

What is self-incompatibility? Why does self-pollination not lead to seed formation in self-incompatible species?

Q.

Mother gives birth to a baby but the baby has characteristics of both parents. How is this possible?

Q.

Why is self pollination bad?

Q. Xenogamy is

1. pollination between two flowers of two different plants
2. pollination between two different flowers of same plant on same branch
3. pollination between anthers and stigma of same flowers
4. a mechanism of parthenocarpy

Q. While planning for an artificial hybridization programme involving dioecious plants, which of the following steps would not be relevant?

1. Collection of pollen
2. Emasculation
3. The dusting of pollen on the stigma
4. Bagging of the female flower

Q. In incomplete dominance

1. The parental phenotypic traits are completely lost in $F_2$ progeny
   
2. Dominant allele reflects its own phenotype in highest proportion in the $F_2$ progeny
   
3. The $F_1$ hybrid expresses a unique visible trait, intermediate of the parental traits.
4. $F_1$ hybrid phenotype resembles the dominant phenotype
   

Q. Define geitonogamy and xenogamy. Give advantages of self-pollination and cross-pollination. Explain how dichogamy favours cross pollination?

Q. Assertion (A): In protandrous flowers like sunflowers, the stamens mature before the carpels
Reason (R): When stamens and carpels mature at different times, self pollination is not possible and cross pollination becomes inevitable

1. Both A and R are false
2. Both A and R are true and R is the correct explanation of A
3. A is true but R is false
4. Both A and R are true and R is not the correct explanation of A

Q. The Jersey bull used for cross breeding is exotic variety from

Q.

Most efficient adaptation that favours cross pollination is Dicliny.

1. True

2. False

Q.

Maturation of stigma before anthers of the same flower is called as protogyny. True or False?

1. True

2. False

Q. Which among the following increases the chances of xenogamy?

1. Homogamy
2. Production of cleistogamous flowers
3. Dicliny
4. Monocliny

Q. Describe two phenomenons which can prevent both autogamy and geitonogamy and ensure xenogamy in flowering plants.

Q.

The whorl that is responsible for attracting agents of pollination usually is the

1. Calyx.

2. Corolla.

3. Androecium.

4. Gynoecium.

Q. Which among the following increases the chances of xenogamy?

1. Homogamy
2. Production of cleistogamous flowers
3. Dicliny
4. Monocliny

Q. Marchantia is considered heterothallic because it is

1. heterogametic
2. bisexual
3. monoecious
4. dioecious

Q. Self-incompatibility prevents pollen tube formation by pollen grains on the stigma of the__________.

1. same flower
2. other flowers of the same plant
3. both a and b
4. none of the above

Q.

Maturation of stigma before anthers of the same flower is called as protogyny. True or False?

1. True

2. False