Science — CBSE Class 10 board question

(i) Three contraceptive techniques and their side effects:

1. Condoms – Barrier method used by males/females. Side effect: slight reduction in sensitivity; may tear or fail if not used correctly.
2. Oral pills – Contain hormones that prevent egg release. Side effect: may cause nausea, irregular bleeding, or hormonal imbalance with long-term use.
3. Copper-T (IUD) – Placed in the uterus to prevent implantation. Side effect: may cause heavy bleeding, cramping, or uterine discomfort.

(ii)

(a) Fertilisation takes place: The fertilised egg (zygote) implants in the uterine wall. The uterus lining is maintained to nourish the developing embryo, and pregnancy begins. Menstruation does not occur.

(b) Egg is not fertilised: The egg and the thickened uterine lining (built up to receive a zygote) are shed. This shedding of the lining along with blood is called menstruation.

Source: Chapter 7 – Reproduction, Section 7.3 Sexual Reproduction

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• Part (i) is worth ~3 marks: name each method + one side effect each — exactly what is needed.
• Part (ii) is worth ~2 marks: one point each for (a) and (b). The key idea in (b) is why menstruation occurs — the uterus lining is shed because fertilisation did not happen.
• Examiners look for: correct name of method, a valid side effect (not vague), and the link between fertilisation/non-fertilisation and uterine lining behaviour.
• "Copper-T" and "oral pills" are the textbook terms — use them exactly.