The mature pollen grain consists of two cells:
- Generative cell: It divides to form two sperm cells during fertilization.
- Vegetative cell: It is larger and controls the growth of the pollen tube.
Match the pollination types in List-I with their correct mechanisms in List-II:
List-I (Pollination Type) | List-II (Mechanism) |
---|---|
A) Xenogamy | I) Genetically different type of pollen grains |
B) Ophiophily | II) Pollination by snakes |
C) Chasmogamous | III) Exposed anthers and stigmas |
D) Cleistogamous | IV) Flowers do not open |
Many of the flowering plants producing hermaphrodite flowers have developed many devices to discourage self-pollination and to encourage cross-pollination. Given below is a picture of one such outbreeding device in a flowering plant. Study the picture and answer the questions that follow:
(a) Explain how the given type of pollination is advantageous to the plant.
(b) Can this flowering plant show geitonogamy? Justify your answer.
A current-carrying coil is placed in an external uniform magnetic field. The coil is free to turn in the magnetic field. What is the net force acting on the coil? Obtain the orientation of the coil in stable equilibrium. Show that in this orientation the flux of the total field (field produced by the loop + external field) through the coil is maximum.
Three students, Neha, Rani, and Sam go to a market to purchase stationery items. Neha buys 4 pens, 3 notepads, and 2 erasers and pays ₹ 60. Rani buys 2 pens, 4 notepads, and 6 erasers for ₹ 90. Sam pays ₹ 70 for 6 pens, 2 notepads, and 3 erasers.
Based upon the above information, answer the following questions:
(i) Form the equations required to solve the problem of finding the price of each item, and express it in the matrix form \( A \mathbf{X} = B \).