Criteria for Autogamy to Take Place

Q.

What are chasmogamous flowers? Can cross-pollination occur in cleistogamous flowers? Give reasons for your answer.

Q. Assertion: Cleistogamous flowers produce assured seed-set even in the absence of pollinators.
Reason : Cleistogamous flowers have exposed anthers and stigma.

1. Both assertion and reason are true and reason is the correct explanation of assertion.
2. Both assertion and reason are true but reason is not the correct explanation of assertion.
3. The assertion is true but reason is false.
4. Both assertion and reason are false.

Q.

What is the disadvantage of cleistogamy?

Q. Which of the following is true about autogamy?
I. Pollen grains are deposited on the stigma of the same flower.
II. It requires synchrony in pollen release and stigma receptivity.
III. Autogamy cannot occur without pollinating agents.
IV. Anthers and stigma needs to be close.

1. I, II and IV are correct
2. Only I and II are correct
3. I, II and III are correct
4. II, III and IV are correct

Q. Autogamy can occur in a chasmogamous flower if_____.

1. pollen matures before maturity of ovule
2. ovules mature before maturity of pollen
3. both pollen and ovule mature simultaneously
4. None of these

Q. Which of the following statements are incorrect?

1. Both b and c
2. Chasmogamous flowers are invariably autogamous.
3. Autogamy introduces new characteristics in progeny.
4. Only autogamy is possible in cleistogamous flowers.

Q.

Mention the three ways in which pollination can occur

Q. Advantage of cleistogamy is

1. No dependence on pollinators
2. Vivipary
3. Higher genetic variability
4. More vigorous offspring

Q. Even in absence of pollinating agents seed-setting is assured in

1. Viola
2. Fig
3. Zostera
4. Salvia

Q. Darwin believed that a giraffe has a long neck because:

1. 
   a creator designed it that way
2. 
   catastrophes eliminated short-necked forms
3. 
   its ancestors stretched their necks to get food
4. ancestral giraffes with slightly longer necks than other got more food and left more surviving offspring

Q.

Under which conditions in flowers autogamy becomes a rule?

Q. In some plants , anthers of stamens and pistil mature at the same time. This is called as

1. Homogamy
2. Syngamy
3. Allogamy
4. Autogamy

Q. Cleistogamous flowers are _______________.

1. wind-pollinated
2. water-pollinated
3. insect-pollinated
4. self-pollinated

Q. Autogamy can occur in a chasmogamous flower if_____.

1. pollen matures before maturity of ovule
2. ovules mature before maturity of pollen
3. both pollen and ovule mature simultaneously
4. None of these

Q.

Describe Stigmatic papillae.

Q.

What is the disadvantage of cleistogamy?

Q. In which type of isolation, two species living in different habitats are prevented from inter-breeding

1. Temporal
2. Behavioural
3. Ecological
4. Genetic

Q. Which of the following is true about autogamy?
I. Pollen grains are deposited on the stigma of the same flower.
II. It requires synchrony in pollen release and stigma receptivity.
III. Autogamy cannot occur without pollinating agents.
IV. Anthers and stigma needs to be close.

1. I, II and III are correct
2. II, III and IV are correct
3. I, II and IV are correct
4. Only I and II are correct

Q.

Name the different factors responsible for cross-pollination.

Q. Cleistogamous flowers are _______________.

1. wind-pollinated
2. water-pollinated
3. insect-pollinated
4. self-pollinated

Q. Assertion: Cleistogamous flowers produce assured seed-set even in the absence of pollinators.
Reason : Cleistogamous flowers have exposed anthers and stigma.

1. Both assertion and reason are true and reason is the correct explanation of assertion.
2. Both assertion and reason are true but reason is not the correct explanation of assertion.
3. The assertion is true but reason is false.
4. Both assertion and reason are false.

Q.

Which of the following is not a criteria for autogamy to occur?

1. Flowers must be bisexual.

2. Flowers require synchrony in pollen release and stigma receptivity.

3. Anthers and stigma should lie close to each other.

4. Flowers should exhibit heterostyly.

Q. Which among the following prevents outbreeding?

1. Chasmogamy
2. Cleistogamy
3. Herkogamy
4. Dichogamy

Q. Advantage of cleistogamy is

1. No dependence on pollinators
2. Vivipary
3. Higher genetic variability
4. More vigorous offspring

Q.

Species is the group of organisms which can interbreed under natural conditions, right? Then, In cross pollination (hybridisation) there is transfer of pollen grains between different species (eg. Pollution btw two species of cotton ) they are interbreeding then how they're in different species??

Q. Which of the following flower is actinomorphic?

1. Pisum
2. Canna
3. Hibiscus
4. None of the above

Q. How does a bisexual flowering plant ensures cross pollination? Explain?

Q. Mention any two contrivances in flowers which favour cross-pollination.

Q. A red four o'clock flower (RR) is crossed with a white four o'clock flower (WW) and the resulting F1 offspring are all pink (RW). If two of the pink offspring are crossed, what proportion of genotypes would you expect to see in the F2 generation?

1. 2 RR: 1 RW: 1 WW
2. 1RR: 2 RW: 1 WW
3. 1 RW: 2 RR: 1 WW
4. 4 RR: 0 RW: 0 WW
5. 2 RR: 0 RW: 2 WW

Q. Pollinators are not required for successful pollination and fertilisation when the flowers exhibit

1. chasmogamy
2. herkogamy
3. dichogamy
4. cleistogamy