What is a Cell ?

When you look around, you see both ______ and ______.

Explanation

Our surroundings contain both living and non-living things.

Living things include plants and animals.

Non-living things include rocks, water and air.

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Conclusion

Living and non-living things are both present in our surroundings.

You must have wondered and asked yourself – ‘what is it that makes an organism living, or what is it that an inanimate thing does not have which a living thing has’?

Explanation

The cell is the basic structural and functional unit of life.

All living organisms are made up of one or more cells.

Non-living things do not possess the cellular organisation characteristic of living organisms.

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Conclusion

The presence of cells is a fundamental characteristic of living organisms.

What is the basic unit of life present in all living organisms?

Explanation

The cell is the basic structural and functional unit of life.

All living organisms are composed of one or more cells.

Cells carry out essential life processes that sustain living organisms.

Inanimate objects do not possess the cellular organisation characteristic of living organisms.

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Conclusion

The cell is the basic unit of life and is present in all living organisms.

All organisms are composed of ______.

Explanation

The cell is the basic structural and functional unit of life.

All living organisms consist of one or more cells.

Unicellular organisms consist of a single cell, whereas multicellular organisms consist of many cells.

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Conclusion

All organisms are composed of one or more cells.

Some organisms are composed of a single cell and are called ______ organisms, while others, like us, are composed of many cells and are called ______ organisms.

Explanation

Unicellular organisms consist of a single cell that performs all essential life processes.

Multicellular organisms consist of many cells, which may be specialised to perform different functions.

Examples of unicellular organisms include Amoeba and Paramecium. Humans are multicellular organisms.

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Conclusion

Organisms consisting of one cell are called unicellular, whereas organisms consisting of many cells are called multicellular.

Unicellular organisms are capable of (i) ______ and (ii) ______ of life.

Explanation

Unicellular organisms consist of a single cell.

That single cell performs all essential life functions, such as nutrition, respiration, excretion and reproduction.

They can exist independently without requiring other cells to form an organism.

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Conclusion

Unicellular organisms can exist independently and perform all essential functions of life within a single cell.

Anything less than a complete structure of a cell does not ensure ______.

Explanation

The cell is the basic structural and functional unit of life.

A complete cellular structure is necessary for independent living.

Cell components alone generally cannot carry out all essential life processes independently.

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Conclusion

A complete cell structure is essential for independent living.

Hence, the cell is the ______ and ______ of all living organisms.

Explanation

The cell is the basic building block of all living organisms.

The structural role of the cell refers to its contribution to the organisation and formation of an organism.

The functional role of the cell refers to its ability to perform essential life processes.

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Conclusion

The cell is the fundamental structural and functional unit of all living organisms.

______ first saw and described a living cell?

Explanation

Antonie van Leeuwenhoek was the first to observe and describe living cells using a microscope.

Robert Hooke observed cork in 1665 and introduced the term “cell” for the small compartments he saw.

Matthias Schleiden and Theodor Schwann later contributed to the development of cell theory.

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Conclusion

Antonie van Leeuwenhoek first observed and described living cells.

______ later discovered the nucleus of the cell?

Explanation

Robert Brown discovered the nucleus in plant cells in 1831.

The nucleus is a cell organelle that contains most of the genetic material in eukaryotic cells.

His discovery contributed significantly to the understanding of cell structure.

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Conclusion

Robert Brown discovered the nucleus in 1831.

The invention of the ______ and its improvement leading to the ______ revealed the structural details of the cell.

Explanation

The microscope enabled scientists to observe cells and their structures.

Improvements in microscopy increased magnification and resolution.

The electron microscope made it possible to study much finer cellular structures than a conventional light microscope.

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Conclusion

The development of microscopes, particularly the electron microscope, greatly improved our understanding of cell structure.