PYQ Vault

Day 97: CBSE Class 10 Science

5 questions (8 parts). Try each one first, then open its answer.

  1. Question 1

    Control and Coordination. Asked once: 2025 (same type asked 3 times)

    29
    Plants have neither a nervous system nor muscles, even then they respond to stimuli. For example, the leaves of chhui-mui (touch-me-not) plant when touched begin to fold up and droop. (a) How is the information communicated in “touch-me-not” plants ? (b) What enables the plant cells to bring out the observable response ? (c) Differentiate the movement mentioned above from the movement of tendrils in a pea plant.

  2. Question 2

    Electricity. Asked once: 2025 (same type asked 3 times)

    26
    State the role of an electric fuse, used in series with an electrical appliance. Why should in an electric circuit a fuse with defined rating not be replaced by one with a larger rating?

  3. Question 3

    Electricity. Asked once: 2025 (same type asked 3 times)

    12
    A piece of wire of resistance ‘R’ is cut lengthwise into three identical parts. These parts are then connected in parallel. If the equivalent resistance of this combination is R′R', then the value of R/R′R/R' is :

    Tap an option to check your answer.

  4. Question 4 (case study, 4 parts)

    Heredity. Asked once: 2023 (same type asked 3 times)

    In some families, either rural or urban, females are tortured for giving birth to a female child. They do not seem to understand the scientific reason behind the birth of a boy or a girl. In fact the mother is not responsible for the sex of the child and it has been genetically proved that the sex of a newborn is determined by what the child inherits from the father.
    38 (a)
    State the basis on which the sex of a newborn baby is determined in humans.
    38 (b)
    Why is the pair of sex chromosomes called a mismatched pair in males ?
    38 (c)
    How is the original number of chromosomes present in the parents restored in the progeny ?
    38 (c) OR
    Explain by giving two examples of the organisms in which the sex is not genetically determined.

  5. Question 5

    How do Organisms Reproduce?. Asked once: 2024 (same type asked 3 times)

    9
    The incorrect statement about placenta is :

    Tap an option to check your answer.