Question 1:
The diagram given below shows labelling of four parts of a dicot embryo during its development as P, Q, R and S. [Diagram]. Choose the option that indicates correct labelling of 'P', 'Q', 'R' and 'S' of embryo in different stages of its development: P, Q, R, S.
Question 2:
How many pollen grains and ovules are likely to be formed in the anther and the ovary of an angiosperm bearing $50$ microspore mother cells and $50$ megaspore mother cells respectively?
Question 3:
Given below is a diagram of T.S. of a monocot seed with parts I, II & III labelled: [Diagram is implied but not provided in text]. Choose the option where parts I, II and III are identified correctly.
Question 4:
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.
(i) Re-bagging
(ii) Selection of parents
(iii) Bagging
(iv) Dusting the pollens on stigma
(v) Emasculation
(vi) Collection of pollens from male parent
(i) Re-bagging
(ii) Selection of parents
(iii) Bagging
(iv) Dusting the pollens on stigma
(v) Emasculation
(vi) Collection of pollens from male parent
Question 5:
Choose the option that correctly describes the gynoecium of Michelia :
Question 6:
Select the statements that are true for the seed of angiosperm from the given options:
(i) Non-albuminous seeds have no residual endosperm.
(ii) Residual, persistent nucellus in wheat is known as perisperm.
(iii) Integuments of ovules harden as tough protective seed coat.
(iv) Metabolic activity of the embryo slows down in dormancy.
Choose the correct option :
(i) Non-albuminous seeds have no residual endosperm.
(ii) Residual, persistent nucellus in wheat is known as perisperm.
(iii) Integuments of ovules harden as tough protective seed coat.
(iv) Metabolic activity of the embryo slows down in dormancy.
Choose the correct option :
Question 7:
Select the statements that are true for pollination mechanism in flowering plants from the given options.
(i) In Vallisneria, the female flowers are pollinated by pollen grains inside the water.
(ii) In Zostera, pollen grains are released on the surface of water.
(iii) In most of the water-pollinated species, pollen grains are covered by a mucilaginous coating.
(iv) Pollination by water is quite rare and limited to about $30$ genera.
Choose the correct answer :
(i) In Vallisneria, the female flowers are pollinated by pollen grains inside the water.
(ii) In Zostera, pollen grains are released on the surface of water.
(iii) In most of the water-pollinated species, pollen grains are covered by a mucilaginous coating.
(iv) Pollination by water is quite rare and limited to about $30$ genera.
Choose the correct answer :
Question 8:
Select the statements that are true for pollination mechanism in flowering plants from the given options.
(i) In Vallisneria, the female flowers are pollinated by pollen grains inside the water.
(ii) In Zostera, pollen grains are released on the surface of water.
(iii) In most of the water-pollinated species, pollen grains are covered by a mucilaginous coating.
(iv) Pollination by water is quite rare and limited to about $30$ genera.
Choose the correct answer :
(i) In Vallisneria, the female flowers are pollinated by pollen grains inside the water.
(ii) In Zostera, pollen grains are released on the surface of water.
(iii) In most of the water-pollinated species, pollen grains are covered by a mucilaginous coating.
(iv) Pollination by water is quite rare and limited to about $30$ genera.
Choose the correct answer :
Question 9:
Select the statements that are true for pollination mechanism in flowering plants from the given options.
(i) In Vallisneria, the female flowers are pollinated by pollen grains inside the water.
(ii) In Zostera, pollen grains are released on the surface of water.
(iii) In most of the water-pollinated species, pollen grains are covered by a mucilaginous coating.
(iv) Pollination by water is quite rare and limited to about $30$ genera.
Choose the correct answer :
(i) In Vallisneria, the female flowers are pollinated by pollen grains inside the water.
(ii) In Zostera, pollen grains are released on the surface of water.
(iii) In most of the water-pollinated species, pollen grains are covered by a mucilaginous coating.
(iv) Pollination by water is quite rare and limited to about $30$ genera.
Choose the correct answer :
Question 10:
Select the statements that are true for a typical dicotyledonous embryo from the given options.
(i) It consists of an embryonal axis and scutellum.
(ii) The portion of embryonal axis above the level of cotyledon is epicotyl.
(iii) The portion of embryonal axis below the level of cotyledon is coleorhiza.
(iv) The lower end of the embryo has radicle covered with a root cap.
Choose the correct answer :
(i) It consists of an embryonal axis and scutellum.
(ii) The portion of embryonal axis above the level of cotyledon is epicotyl.
(iii) The portion of embryonal axis below the level of cotyledon is coleorhiza.
(iv) The lower end of the embryo has radicle covered with a root cap.
Choose the correct answer :
Question 11:
A phenomenon where a male insect mistakenly identified the patterns of a orchid flower as the female insect partner, and tries to copulate and thereby pollinates the flower is said to be :
Question 12:
Identify the correct labellings in the figure of a fertilised embryo sac of an angiosperm given below :
[Diagram with A, B, C, D and Primary Endosperm Cell (PEC)]
[Diagram with A, B, C, D and Primary Endosperm Cell (PEC)]
Question 13:
(A) (i) Write two crucial changes, the seed undergoes while reaching maturity that enable them to be in a viable state until the onset of favourable conditions.
(ii) Name the oldest viable seed excavated from Arctic Tundra as per the records.
(ii) Name the oldest viable seed excavated from Arctic Tundra as per the records.
Question 14:
OR (B) (i) Pea flower produce assured seed sets. Give reason.
(ii) In case of Polyembryony, an embryo 'P' develops from a synergid and the embryo 'Q' develops from the nucellus. State the ploidy of embryo 'P' and 'Q'.
(ii) In case of Polyembryony, an embryo 'P' develops from a synergid and the embryo 'Q' develops from the nucellus. State the ploidy of embryo 'P' and 'Q'.
Question 15:
"Farmers prefer apomictic seeds to hybrid seeds." Justify giving two reasons.
Question 16:
(a) A bilobed dithecous anther has 200 microspore mother cells per microsporangium. How many male gametophytes can be produced by this anther?
(b) Write the composition of intine and exine layers of a pollen grains.
(b) Write the composition of intine and exine layers of a pollen grains.
Question 17:
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.
[Table is implied showing results of cross and self-pollination]
Note: All plants belong to the same species. X - No pollen tube growth/inhibition of pollen germination on stigma. $\checkmark$ - Pollen germination on stigma.
[Table is implied showing results of cross and self-pollination]
Note: All plants belong to the same species. X - No pollen tube growth/inhibition of pollen germination on stigma. $\checkmark$ - 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.
Question 18:
Given below is a flower with its characteristic features specialised for the most common type of abiotic pollination. [Diagram is implied with labels: Feathery stigma, Versatile Anther, Ovary, Petals]
Answer the following questions based on the above diagram:
(a) Name the mode of abiotic pollination that will be adopted by the given plant species in the above picture.
(b) State the need of exposed large feathery stigmas for the flower.
(c) What will be the two important adaptations in the pollen grains of the flowers pollinated by the above mode of pollination?
(d) What could be the probable reason for the petals being small and non-green ?
Answer the following questions based on the above diagram:
(a) Name the mode of abiotic pollination that will be adopted by the given plant species in the above picture.
(b) State the need of exposed large feathery stigmas for the flower.
(c) What will be the two important adaptations in the pollen grains of the flowers pollinated by the above mode of pollination?
(d) What could be the probable reason for the petals being small and non-green ?
Question 19:
If the cells in the leaves of a maize plant contain 10 chromosomes each, write the number of chromosomes in its endosperm and zygote. Name and explain the process by which an endosperm and a zygote are formed in maize.
Question 20:
(A) (a) Distinguish between the two cells enclosed in a mature male gametophyte of an angiosperm.
(b) Study the diagram given below showing the modes of pollination. Answer the questions that follow. [Diagram].
(i) The given diagram shows three methods of pollen transfer in plants. Examine them carefully and write the technical terms used for pollen transfer methods '1', '2' and '3'.
(ii) How do the following plants achieve pollination successfully? (a) Water lily, (b) Vallisneria.
(iii) Write advantages of pollen transfer in method '3'.
Question 21:
(a) (i) Explain the structure of a mature embryo sac of a typical flowering plant.
(ii) How is triple fusion achieved in these plants ?
OR
(b) Describe the changes in the ovary and the uterus as induced by the changes in the level of pituitary and ovarian hormones during menstrual cycle in a human female.
(ii) How is triple fusion achieved in these plants ?
OR
(b) Describe the changes in the ovary and the uterus as induced by the changes in the level of pituitary and ovarian hormones during menstrual cycle in a human female.
Question 22:
(a) (i) Explain how does double fertilisation take place in a flowering plant.
(ii) Write the fate of the products of double fertilization in these plants.
OR
(b) (i) Explain the structure of testicular lobules in human male reproductive system. Name the two types of cells present in the seminiferous tubules and state their role.
(ii) Describe the role of hypothalamic hormone GnRH in spermatogenesis.
(ii) Write the fate of the products of double fertilization in these plants.
OR
(b) (i) Explain the structure of testicular lobules in human male reproductive system. Name the two types of cells present in the seminiferous tubules and state their role.
(ii) Describe the role of hypothalamic hormone GnRH in spermatogenesis.
Question 23:
**OR**
(i) With the help of labelled diagram only, show the different stages of embryo development in a dicot plant.
(ii) Endosperm development precedes embryo development. Justify.
(i) With the help of labelled diagram only, show the different stages of embryo development in a dicot plant.
(ii) Endosperm development precedes embryo development. Justify.
Question 24:
The following question is based on pollination. Study the figures carefully and answer the questions that follow. [Figures A and B are implied, showing different types of pollination]
- (a) Give the scientific terms for the processes taking place in Figures A and B respectively.
- (b) Mention two conditions necessary for the process occurring in Figure B.
- (c) (i) State one advantage and one disadvantage of the process occurring in Figure B.
OR
(c) (ii) Name one plant where, in some flowers only, the process in Figure B takes place and give the reason responsible for it.