What is apomixis and what is its importance?
Solution and Explanation
Apomixis is the mechanism of seed production without involving the process of meiosis and syngamy. It plays an important role in hybrid seed production. The method of producing hybrid seeds is difficult to maintain hybrid characters as characters segregateduring meiosis. Apomixis prevents the loss of specific characters in the hybrid. Also, it is acost-effective method for producing seeds.
Top Questions on sexual reproduction in flowering plants
Flowering plants with hermaphrodite flowers have developed many reproductive strategies to ensure cross-pollination. Study the given outbreeding devices adopted by certain flowering plants and answer the questions that follow.
Note : All plants belong to the same species. No pollen tube growth/inhibition of pollen germination on stigma. Pollen germination on stigma.- [(a)] Name and define the outbreeding device described in the above table.
- [(b)] Explain what would have been the disadvantage to the plant in the absence of the given strategy.
- CBSE CLASS XII - 2025
- Biology
- sexual reproduction in flowering plants
- Student to attempt either option (A) or (B): (A) What is meant by ‘right’ and ‘wrong’ type of pollen when pollen lands on the stigma? A two-celled right type pollen has landed on the stigma. Explain the events taking place till fertilization in angiosperms. Why is pollen pistil interaction said to be dynamic?
OR
(B)- Give the schematic representation of oogenesis in human females indicating chromosome number at each step.
- In which part of the female reproductive system do the following events take place?
- I. Formation of corpus luteum
- II. Maturation of tertiary follicle
- III. Fertilisation
- IV. Implantation
- CBSE CLASS XII - 2025
- Biology
- sexual reproduction in flowering plants
The following question is based on pollination. Study the figures carefully and answer the questions that follow.
- Give the scientific terms for the processes taking place in Figures A and B respectively.
- Mention two conditions necessary for the process occurring in Figure B.
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- [(i)] State one advantage and one disadvantage of the process occurring in Figure B.
OR - [(ii)] Name one plant where, in some flowers only, the process in Figure B takes place and give the reason responsible for it.
- [(i)] State one advantage and one disadvantage of the process occurring in Figure B.
- CBSE CLASS XII - 2025
- Biology
- sexual reproduction in flowering plants
- Choose the option that correctly describes the gynoecium of Michelia:
- CBSE CLASS XII - 2025
- Biology
- sexual reproduction in flowering plants
- Given below are the events that are observed in an artificial hybridisation programme. Arrange them in the correct sequential order and select the correct option.
- Re-bagging
- Selection of parents
- Bagging
- Dusting the pollens on stigma
- Emasculation
- Collection of pollens from male parent
- CBSE CLASS XII - 2025
- Biology
- sexual reproduction in flowering plants
Questions Asked in CBSE CLASS XII exam
- ‘But the game he is watching so intently is out of his reach.’ What are the factors that have made their game inaccessible to Saheb? (Lost Spring)
- CBSE CLASS XII - 2025
- Literature
- The basic scheme of the essential steps involved in the process of recombinant DNA technology is summarised below in the form of a flow diagram. Study the given flow diagram and answer the questions that follow: \begin{center} Step-1 \quad Plasmid DNA (cut using Restriction Enzyme EcoR I) \quad + \quad Foreign DNA (cut using Restriction Enzyme EcoR I)
$\downarrow$
DNA ligase
$\downarrow$
Step-2 \quad Recombinant DNA molecule
$\downarrow$
Step-3 \quad Transfer of recombinant DNA molecule to the host cell
$\downarrow$
Step-4 \quad Replication of recombinant DNA molecule in the host cell \end{center} (a) Name the specific enzyme that might have been used to make the multiple copies of foreign DNA before undergoing Step-1 of the process.
(b) How does the use of restriction enzyme EcoR I in Step-1 facilitate the action of DNA ligase to form the recombinant DNA molecule? Explain.
(c) Name the most commonly used host in the above process.- CBSE CLASS XII - 2025
- Biotechnology
- Draft an invitation card on behalf of the Principal of J.B. Bhatia Public School for the launch of ‘Yoga for Life’ programme in the school. Mention a compelling highlight of the programme along with other necessary details.
- CBSE CLASS XII - 2025
- Letter Writing
- What is the difference between CRS and GDS?
- CBSE CLASS XII - 2025
- Hotel Operations
- What is the significance of reservation to the guest?
- CBSE CLASS XII - 2025
- Hotel Operations
Notes on sexual reproduction in flowering plants
Concepts Used:
Sexual Reproduction in Flowering Plants
Sexual reproduction in flowering plants takes place or happens when the production of a new organism occurs from two parents by making use of their gametes or sex cells. Both sexual and asexual reproduction can be found in plants. Nearly all flowering plants reproduce sexually. Flowers play a captious role in the process as it carries both the male and female reproductive parts commonly known as androecium and gynoecium respectively.
An individual flower comprises the following parts -
- Pedicle
- Calyx
- Petals
- Sepals
- Stamen
- Pistil
- Receptacle