Check sibling questions

The given diagram represent the structure of a flower. Study the structure and answer any four questions from (a) to (e).

Q3 - The give diagram - Teachoo.jpg

(a) The labels A, B and C are

(i) Anther, Style and Ovary respectively.

(ii) Stamen, Stigma and Ovule respectively.

(iii) Anther, Style and Stigma respectively.

(iv) Stamen, Fragment and Ovary respectively.

 

(b) Which of these is the function of part labelled as C?

(i) Contains ovules which develop into seeds.

(ii) Attracts pollinators.

(iii) Protect rising buds.

(iv) Receive pollens

 

(c) When an insect sits on the flower of a plant then some particles from the little stalks in the flowers sticks to its body and when this insect sits on the flower of another plant, the particles get deposited in that flower. What are these particles?

(i) Dust

(ii) Pollens

(iii) Grains

(iv) Seeds

 

(d) A student decides to study the impact of removing certain flower parts on fruit formation in plant species X. He chooses three separate plants that are growing in the same plot under uniform conditions. The data is given in the table below.

Plants Part Removed   Impact on formation
1 Anther 30% less fruit formed  than average plants in  the plot
2 Stigma  No fruit formed
3 Petal  No significant

Which of the following can be inferred from the above data?

(i) Anthers and stigmas are crucial in sexual reproduction in species X.

(ii) Pollen grains are probably unable to germinate if they land on other parts of the carpel besides the stigma.

(iii) Species X is likely to be wind-pollinated.

(iv) Species X relies completely on crosspollination.

 

(e) In a flowering plant, summarize the events that take place after fertilization.

 

Answer:

(a)

PARTS OF A FLOWER - Teachoo.png

The labels A,B and C are (i) Anther, Style and Ovary respectively. 

(b)

Part C is the ovary.

Functions of ovary are:

  • Make ovules.
  • Store ovules.

Checking the options:

  • (i) Contains ovules which develop into seeds - This is a function of the ovary. 
  • (ii) Attracts pollinators - Not a function of the ovary.
  • (iii) Protect rising bud - Not a function of the ovary.
  • (iv) Receive pollens - Not a function of the ovary.

So, the correct answer is (i).

(c)

Pollen grains are particles which help in pollination and they are transferred from one flower to another through insects, animals, wind and water.

CROSS POLLINATION - Teachoo.png

So, the correct answer is (ii) pollens.

(d)

It can be inferred from the above data that:

  • The removal of anthers affects fruit formation in plant 1, this implies that species X  relies partially on self-pollination. 
  • The removal  of either anthers or stigmas affects the rate of fruit formation significantly.
  • No fruits are observed when the stigmas in plant 2 are removed. This shows that pollen grains are probably unable to germinate if they land on any other part of the carpel besides the stigma. 
  • The petals do not seem to play a significant role in facilitating fruit formation. 

Checking the options:

  • (i) Anthers and stigmas are crucial in sexual reproduction in species X - Can be inferred from the above data.
  • (ii) Pollen grains are probably unable to germinate  if they land on other parts of the carpel besides  the stigma - Cannot be inferred from the above data.
  • (iii) Species X is likely to be wind-pollinated - Cannot be inferred from the above data.
  • (iv) Species X relies completely on cross-pollination - Cannot be inferred from the above data.

So, the correct answer is (i).

(e)

Events that take place after fertilisation are:

EVENTS THAT TAKE PLACE AFTER FERTILISATION ARE - Teachoo.png


Transcript

CROSS POLLINATION PARTS OF A FLOWER Anther Filament Stigma Style Ovary Receptacle Sepal EVENTS THAT TAKE PLACE AFTER FERTILISATION ARE Fertilisation Formation of zygote Formation of Embryo The zygote divides several times to form an embryo within the ovule Seed Formation The ovule develops a tough coat around it and gradually develops into a seeds Seed Formation The ovary develops and becomes a fruit

CA Maninder Singh's photo - Co-founder, Teachoo

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CA Maninder Singh

CA Maninder Singh is a Chartered Accountant for the past 12 years and a teacher from the past 16 years. He teaches Science, Economics, Accounting and English at Teachoo