Skip to content

(i) Name the disorder which… (Class 10 Science 2023, Q35b)

questionbuddy.in/q/cbse-10-science-2023-31-2-1-q35b-name-disorder-person-likely-suffer

ScienceCBSE Class 10 · Board exam 2023, set 31/2/1 · 5 marks · Long answer

CBSE Class 10 Science 2023: question 35(b)

Set in the CBSE Class 10 board exam of 2023, paper 31/2/1, section D, question 35(b), for 5 marks. Try it first; the hints and our step-by-step solution are below.

Q35(b) · 5 marks · Long answerControl and Coordination

(i) Name the disorder which a person is likely to suffer from due to the following : (I) Over-secretion of growth hormone (II) Deficiency of oestrogen in females (III) Less secretion of thyroxine. Also name the gland that secretes each of the hormones mentioned above.
(ii) How is the timing and amount of hormone released regulated ? Explain with the help of an example.

Source: official question paper from cbse.gov.in (PDF). See it in the full 2023 board paper, set 31/2/1.

Hints

Open one hint at a time and try again before the next.

Hint 1

Think about which gland makes growth hormone, oestrogen and thyroxine.

Hint 2

Too much growth hormone causes abnormal height. Too little thyroxine causes a swelling in the neck.

Hint 3

For (ii), recall how the pancreas responds when blood sugar goes up or down.

Step-by-step solution

Each step shows the marks it earns, as an examiner would award them. Checked by an independent re-solve from the question paper.

  1. (i)(I) Over-secretion of growth hormone causes gigantism. The hormone is secreted by the pituitary gland.

    1 mark

  2. (i)(II) Deficiency of oestrogen in females causes delayed puberty (secondary sexual characters do not develop in time). Oestrogen is secreted by the ovaries.

    1 mark

  3. (i)(III) Less secretion of thyroxine causes goitre (swelling in the neck). Thyroxine is secreted by the thyroid gland.

    1 mark

  4. (ii) The timing and amount of hormone released are controlled by a feedback mechanism. The level of the substance that the hormone controls signals the gland to increase or decrease its secretion.

    1 mark

  5. (ii) Example: insulin from the pancreas. When the blood sugar level rises, the pancreas detects it and secretes more insulin. As the blood sugar level falls, insulin secretion is reduced.

    1 mark

Answer: (i) (I) Gigantism – pituitary; (II) Delayed puberty – ovary; (III) Goitre – thyroid. (ii) By a feedback mechanism, e.g. a rise in blood sugar increases insulin secretion and a fall in blood sugar reduces it.

Where the marks are

  • Gigantism and pituitary gland (½ + ½ mark)
  • Delayed puberty and ovary (½ + ½ mark)
  • Goitre and thyroid gland (½ + ½ mark)
  • States that a feedback mechanism regulates timing and amount (1 mark)
  • Insulin–blood sugar example explained correctly (1 mark)

Revise the chapter

Practise this chapterBoard-style questions from Control and Coordination, one at a time, marked against the answer key and marking points.Back to the full paper2023 board paper, set 31/2/1: every question, by section.

The question is transcribed from the official paper; figures are described in words. The solution, hints and chapter tag are ours. Spotted an error? Write tosupport@questionbuddy.in.