Given below is a flower with its characteristic features specialised for the most common type of abiotic pollination.
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?
(a) The mode of abiotic pollination depicted is anemophily (pollination by wind).
(b) Exposed large feathery stigmas are needed to effectively trap airborne pollen grains from the environment, increasing the chances of successful pollination.
(c) The two important adaptations of pollen grains for wind pollination are:
(d) The petals are small and non-green because they do not need to attract pollinators (like insects or animals), as the plant relies on wind rather than biotic agents for pollination.
Student to attempt either option (A) or (B).
(A)
(i) Describe the process of megasporogenesis in an angiosperm.
(ii) Draw a diagram of a mature embryo sac of the angiosperm. Label its any four parts.
OR
(B) The reproductive cycle in the female primates is called menstrual cycle. The first menstruation begins at puberty.
Answer the following questions:
(i) Name the four phases of menstrual cycle in a proper sequence.
(ii) How long does the menstrual phase last in a menstrual cycle?
(iii) When and why hormones estrogen and progesterone reach their peak levels respectively, in the menstrual cycle?
(iv) Give the significance of LH surge.
Student to attempt either option (A) or (B):
(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.
OR (B)
(i) Pea flower produced 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’.
Given below is a diagram of T.S. of a monocot seed with parts I, II & III labelled :
Choose the option where parts I, II and III are identified correctly.
Bittu and Chintu were partners in a firm sharing profit and losses in the ratio of 4:3. Their Balance Sheet as at 31st March, 2024 was as
On $1^{\text {st }}$ April, 2024, Diya was admitted in the firm for $\frac{1}{7}$ share in the profits on the following terms:
Prepare Revaluation Account and Partners' Capital Accounts.
(a) Calculate the standard Gibbs energy (\(\Delta G^\circ\)) of the following reaction at 25°C:
\(\text{Au(s) + Ca\(^{2+}\)(1M) $\rightarrow$ Au\(^{3+}\)(1M) + Ca(s)} \)
\(\text{E\(^\circ_{\text{Au}^{3+}/\text{Au}} = +1.5 V, E\)\(^\circ_{\text{Ca}^{2+}/\text{Ca}} = -2.87 V\)}\)
\(\text{1 F} = 96500 C mol^{-1}\)