Cell Structure and Reproduction (Class 8)

What this worksheet covers

This is an eighteen-question practice worksheet on cell structure and reproduction in animals for Class 8, written to the pattern of the SOF National Science Olympiad (NSO). It carries 24 marks and is designed to be attempted in 45 minutes, split across three sections — Scientific Reasoning, Applying What You Know and Achievers Section. Every question is multiple choice with exactly one correct option, and every one comes with a fully worked solution rather than just an answer key — so a child who gets one wrong can see where the reasoning went astray instead of only learning that it did.

Skills your child practises

• Applied problem-solving on cell structure and reproduction in animals at Class 8 level
• Working accurately against a time limit, as the real paper demands
• Scientific Reasoning questions in the olympiad format
• Applying What You Know questions in the olympiad format
• Achievers Section questions in the olympiad format
• Reading worked solutions to find the step that went wrong

How to use it

1. 1There are 18 questions in this worksheet. All questions are compulsory.
2. 2Each question has four options (A), (B), (C) and (D). Exactly one option is correct.
3. 3Questions 1–15 carry 1 mark each. Questions 16–18 (Achievers Section) carry 3 marks each.
4. 4There is no negative marking. Study every diagram and table carefully.

Sample questions from this worksheet

A preview of what's inside Cell Structure and Reproduction (Class 8) — the PDF has the full set, and every question comes with a worked solution like these.

1. 1. The basic structural and functional unit of all living organisms is the _______.

   • ATissue
   • BNucleus
   • COrgan
   • DCellcorrect
   Solution: The cell is the basic unit of life. Some organisms consist of a single cell, while others are made of billions of them.

2. 2. Why is the plant cell's large central vacuole important for a wilting plant?

   • AIt stores chlorophyll
   • BIt divides the cell
   • CIt carries out photosynthesis
   • DWhen full of water it presses outward and keeps the cell firm, so the plant stays uprightcorrect
   Solution: A full vacuole presses outward against the cell wall and keeps the cell firm, which keeps soft stems and leaves upright. When the plant loses water the vacuoles shrink, the cells go limp and the plant wilts.

3. 3. Consider the following statements.(i) All cells have a nucleus with a well-defined nuclear membrane.(ii) The nerve cell is one of the longest cells in the human body.(iii) An egg of a hen is a single cell.Which of the statements is/are correct?

   • A(i) and (ii) only
   • B(ii) and (iii) onlycorrect
   • C(i) and (iii) only
   • DAll three
   Solution: Statement (i) is false — bacteria have no nuclear membrane, so their genetic material lies free in the cytoplasm; such cells are called prokaryotic. Statement (ii) is true; nerve cells can be very long indeed. Statement (iii) is true; the yolk of a hen's egg is a single enormous cell. Hence (ii) and (iii).