Friday, June 15, 2012

Class 8/9 The Cell and Its structure and Functions solved

1. Name the person who first coined the term “Cell”

Ans: Robert Hooke in 1665, first coined the term Cell.

2. Define Cell

Ans: Cell is defined as the basic structural and functional unit of living organisms.

3. What will happen to a cell if its nucleus is removed?

Ans: With the passage of time, the cell will die as the nucleus which controls and coordinates all the functions of the cell is absent.

4. Give 5 examples of single celled organisms.

Ans: Paramecium, Amoeba, Chlamydomonas, Bacteria, Malarial Parasite

5. What are multicellular organisms ? Give an example.

Ans: The organisms consisting of more than one (multiple) cells, where each cell performs a specialized function is known as Multicellular Organism. Example:- Animals, Plants, Fungi

6. The cell organelle which is commonly referred as the suicidal bags of the cell.

Ans: Lysosomes.

7. Name the process through which an amoeba acquires its food from the external surroundings.

Ans: The process through which an amoeba acquires its food from the external environment is called Endocytosis.

8. State the functions of chromosome in a cell.

Ans: Chromosome is the carrier of genetic information.

9. Who proposed the Cell theory ?

Ans: Schielden and Schwann proposed the cell theory (i.e. all organisms have cell and cell is the basic unit of life), it was further expanded by Virchow (by suggesting that all cells arise from pre-existing cells).

10. What is Nucleoid ?

Ans: The undefined nuclear region of Prokaryotic cell (Bacteria, Blue Green Algae) is known as Nucleoid.

11. Define diffusion.

Ans: Diffusion is defined as the movement of particles from a region of High Concentration to a region of low concentration.

12. Plasma membrane is formed of?

Ans: Plasma Membrane is formed of Proteins and Lipids.

13. Identifiy and name the following cell structures: 
 a) The undefined nuclear region of Prokaryotic cell.
 b) Site of energy release inside the cell.

Ans: a) Nucleoid b) Mitochondria

14. Name the kind of plastid which is important for photosynthesis in leaves of the plants.

Ans: Chloroplast.

15. Name the two components of chromosomes.

Ans: Proteins and DNA.

16. When does the chromatin network separate out to form chromosomes?

Ans: The network of Chromatin fibres seperate out to form chromosomes, when a cell is at dividing stage (dividing/about to divide).

17. Name the cell organelle that detoxifies poisons and drugs.

Ans: Smooth Endoplasmic Reticulum (SER).

18. Name the cell organelle that is associated with protein synthesis.

Ans: Ribosomes.

19. Name a cell which changes its shape.

Ans: Amoeba

20. Name the functional unit of DNA that carries genetic informations.

Ans: Genes

20. Expand the word DNA.

Ans: Deoxyribo Nucleic Acid.

21. State the primary functions of plasma membrane.

Ans: It regulates the exchange of materials between the cytoplasm and extracellular fluids.

22. Name a cell that lacks cell wall

Ans: Animal Cells

23. Name the main constituent substance present in plant cell wall.

Ans: Cellulose

24. Name the cell which is responsible for intracellular transport.

Ans: Endoplasmic Reticulum

25. Name the Reticulum which has ribosome’s attached to it .

Ans: Rough Endoplasmic Reticulum

26. Name a cell that does not have a nucleus, what are they called?

Ans: The cells that do not have a nucleus are called Enucleate Cells, Red Blood Cells (RBC) is a enucleate cell..

27. What is Biogenisis?

Ans: The production of proteins and lipids for producing membrane by the SER is known as Biogenises.

28. Who discovered Golgi Apparatus?

Ans: Camillo Golgi.

29. Name the cell organelle which is involved in the formation of lysosomes.

Ans: Golgi Aparatus.

What is Endosmosis?

Ans: The passage (entry) of water from outside to inside of a cell is known as Endosmosis.

Download links

IX The Cell & Fundamental Unit of life -MCQ Unsolved
IX The Cell & Fundamental Unit of life -MCQ Solved
The Cell & Fundamental Unit of life -Test Paper
The Cell & Fundamental Unit of life -Notes
The Cell & Fundamental Unit of life -Chapter Notes
The Cell & Fundamental Unit of life - Extra Score Notes
The Cell & Fundamental Unit of life -Solved test Paper
The Cell & Fundamental Unit of life -Test Paper
Extra mind Solved Question paper: Ch: The Cell

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