1. Post-fertilisation, the zygote formed in the ovule develops into an embryo. The ovules mature into seeds, while the ovary enlarges and transforms into a fruit, enclosing the seeds. Other floral parts like petals and sepals usually dry and fall off. This sequence of changes ensures seed protection, dRead more

    Post-fertilisation, the zygote formed in the ovule develops into an embryo. The ovules mature into seeds, while the ovary enlarges and transforms into a fruit, enclosing the seeds. Other floral parts like petals and sepals usually dry and fall off. This sequence of changes ensures seed protection, dispersal, and continuation of the plant species through fruit formation.

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  2. Urine formation helps in excretion by removing harmful nitrogenous wastes like urea, uric acid, and excess water. This process maintains the body’s chemical balance and prevents accumulation of toxins. Urine is stored in the urinary bladder until excretion, and when the bladder contracts, it is releRead more

    Urine formation helps in excretion by removing harmful nitrogenous wastes like urea, uric acid, and excess water. This process maintains the body’s chemical balance and prevents accumulation of toxins. Urine is stored in the urinary bladder until excretion, and when the bladder contracts, it is released out of the body through the urethra. This ensures proper waste removal and homeostasis.

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  3. Arteries transport blood from the heart under high pressure, so they need thick and elastic walls to resist and maintain this pressure without damage. In contrast, veins carry blood back to the heart at low pressure. To prevent blood from flowing backwards due to gravity, veins are provided with valRead more

    Arteries transport blood from the heart under high pressure, so they need thick and elastic walls to resist and maintain this pressure without damage. In contrast, veins carry blood back to the heart at low pressure. To prevent blood from flowing backwards due to gravity, veins are provided with valves. Thus, arteries manage pressure, while veins ensure correct direction of blood flow.

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  4. (a) When a ray travels from A (refractive index 1.6) to B (1.8), it moves from a rarer to a denser medium. In this case, the speed of light decreases, causing the ray to bend towards the normal. Therefore, the bending towards the normal occurs only in the transition from medium A to medium B. (b) WhRead more

    (a) When a ray travels from A (refractive index 1.6) to B (1.8), it moves from a rarer to a denser medium. In this case, the speed of light decreases, causing the ray to bend towards the normal. Therefore, the bending towards the normal occurs only in the transition from medium A to medium B.

    (b) When the ray moves from B (refractive index 1.8) to C (1.5), it passes from a denser to a rarer medium. Light travels faster in a medium with lower refractive index. Thus, in medium C, with refractive index 1.5, the speed of light increases compared to medium B, because of the inverse relationship between refractive index and velocity.

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  5. ANSWER: (A) Electrolytic decomposition of water/electrolysis of water. (B) The gas collected at cathode is hydrogen which is double the volume of oxygen collected at anode. (C) 2H2O (l) + Electric current → 2H2 (g) + O2 (g) When an electric current is passed through water, it undergoes electrolysis.Read more

    ANSWER:

    (A) Electrolytic decomposition of water/electrolysis of water.

    (B) The gas collected at cathode is hydrogen which is double the volume of oxygen collected at anode.

    (C) 2H2O (l) + Electric current → 2H2 (g) + O2 (g) When an electric current is passed through water, it undergoes electrolysis. Two molecules of liquid water (2H₂O) decompose to form hydrogen gas (2H₂) and oxygen gas (O₂). Hydrogen collects at the cathode, while oxygen collects at the anode.

    (D) Water is not a good conductor of electricity sulphuric acid is added in the water to make, it a good conductor of electricity.

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