If one can induce parthenocarpy through the application of growth substances which fruits would you select to induce parthenocarpy and why?
Solution and Explanation
Parthenocarpy is the process of developing fruits without involving the process of fertilization or seed formation. Therefore the seedless varities of economically important fruits such as oranges, lemon, watermelon etc. are produced using this technique. This technique involves induces fruit formation by the application of plant growth hormones such as auxins.
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.
-
- [(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
- A coil of 60 turns and area \( 1.5 \times 10^{-3} \, \text{m}^2 \) carrying a current of 2 A lies in a vertical plane. It experiences a torque of 0.12 Nm when placed in a uniform horizontal magnetic field. The torque acting on the coil changes to 0.05 Nm after the coil is rotated about its diameter by 90°. Find the magnitude of the magnetic field.
- CBSE CLASS XII - 2025
- Magnetism and matter
- Determine the values of $x$ for which the function $f(x) = \frac{x-4}{x+1}$ is an increasing or a decreasing function.
- CBSE CLASS XII - 2025
- Application of derivatives
Complete and balance the following chemical equations: (a) \[ 2MnO_4^-(aq) + 10I^-(aq) + 16H^+(aq) \rightarrow \] (b) \[ Cr_2O_7^{2-}(aq) + 6Fe^{2+}(aq) + 14H^+(aq) \rightarrow \]
- CBSE CLASS XII - 2025
- Redox Reactions
- Two wires of the same material and the same radius have their lengths in the ratio 2:3. They are connected in parallel to a battery which supplies a current of 15 A. Find the current through the wires.
- CBSE CLASS XII - 2025
- Current electricity
- Arun, Bashir and Joseph were partners in a firm sharing profits and losses in the ratio of 5 : 3 : 2. They admitted Daksh as a new partner who acquired his share entirely from Arun. If Arun sacrificed \( \frac{1}{5} \)th from his share to Daksh, Daksh's share in the profits of the firm will be :
- CBSE CLASS XII - 2025
- Partnership Accounts
Concepts Used:
Post-Fertilization Events
There are series of events that happen in the development of plants after their fertilization process to form a fruit from a diploid zygote. The four different developmental steps that occurs during post fertilization are:
- Development of an Endosperm: The endosperm, a tissue, present in the seed during the fertilization, precedes the development of an embryo. It is categorized into three types.
- Nuclear Formation
- Cellular Formation
- Helobial Formation
- Development of an Embryo: Embryogeny is the embryo development process and it starts developing at the micropylar end of the embryo sac in the zygote. The formation stages of embryogeny are almost the same in both the plants dicot and monocot, regardless of their structure.
- Monocot Embryo
- Dicot Embryo
- Development of a Seed: A Seed has Three Body Parts:
- Seed Coat
- Cotyledon
- Embryo Axis
- Formation of a Fruit: After the cell division and separation in the ovary, it is changed into fruit because of stimuli received from fertilization just as developing seed. The pericarp which might be fleshy like guava, tomato, or cucumber or might be weathered and dry like pea, bean, or mustard. After all the events the two types of fruits are formed:
- True Fruit
- False Fruit