Biology

The Fundamental Unit of Life

Question:

Are there any exceptions to cell theory proposed by Schleiden & Schwann and Virchow? If yes, what are those?

Answer:

Yes there are exceptions to cell theory. These are:
  1. Cell theory do not explain nature of Virus. They become live and multiply though they are made up of non-living material.
  2. How come the first living cell originated or how life began on the earth. (Scientists J.B.S. Haldane, Stanley L. Miller and Harold C. Urey did experiments to on this.).
  3. Mitochondria and chloroplasts have their own genetic material and can reproduce independently.
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The Fundamental Unit of Life

Q 1.

Which cell organelle is known as 'protein factory'?

Q 2.

Identify cell organelle and write down its name:
A tough, non-living layer, it prevents plant cells from bursting, freely permeable

Q 3.

Which cell organelle is called 'kitchen of plant'?

Q 4.

What is the plasma membrane composed of?

Q 5.

Is plasma membrane permeable or selectively permeable?

Q 6.

Are plastids present in all cells? What are its types?

Q 7.

What are chromosomes?

Q 8.

What is the full form of DNA and RNA?

Q 9.

Why is mitochondria absent in red blood cells?

Q 10.

Which of the following cell is better candidate to study lysosomes?
(a) White Blood Cell
(b) Muscle Cell

Q 11.

Name the two postulates of the cell theory.

Q 12.

Name the biggest cell in human body.

Q 13.

Name the sac like structure which form the grana?

Q 14.

Define Cell

Q 15.

Identify cell organelle and write down its name:
A network of flattened cavities surrounded by a membrane, which links with the nuclear membrane. Help in packaging proteins.

Q 16.

Identify cell organelle and write down its name:
Digestive organelle where macromolecules are hydrolyzed

Q 17.

Who observed the cells the first time?

Q 18.

Who coined the term 'protoplasm'?

Q 19.

Give an example of anucleate cell i.e. cell without nucleus.

Q 20.

What are different types transport of components across cell membrane?

Q 21.

What are the conditions for osmosis?

Q 22.

What are the function of nucleus?

Q 23.

Identify cell organelle and write down its name:
Slipper or oval shaped, its inner membrane is multi-folded and has lot of chemical activity

Q 24.

Who proposed the cell theory?

Q 25.

Name the smallest cell in human body.

Q 26.

What is plasmolysis?

Q 27.

Will the temperature have any effect on the process of the osmosis?

Q 28.

Which organ of the plant body helps in osmoregulation?

Q 29.

Identify cell organelle and write down its name:
Called 'suicide bags' of a cell.

Q 30.

What is diffusion?

Q 31.

When chromosomes are visible in the nucleus?

Q 32.

Identify cell organelle and write down its name:
Powehouse of cell

Q 33.

In which year electron microscope was invented?

Q 34.

Which cell organelle is called 'control center'?

Q 35.

Identify cell organelle and write down its name:
A partially permeable layer prevents cell contents from escaping controls what substances enter and leave the cell. Identify?

Q 36.

Who proposed fluid-mosaic model of cell or plasma membrane?

Q 37.

Why can't single cells grow very large? Or Big organisms like human beings are multi-cellular? Why can't such big organisms be a single large cell?

Q 38.

Identify cell organelle and write down its name:
Contains green colour pigment, traps light energy. Present in some plant cells.

Q 39.

Give examples of cells which are muti-nucleate (i.e. having many nuclei).

Q 40.

Who is known as 'Father of Microscopy'?

Q 41.

Which cell organelle is called 'transport system'?

Q 42.

What is the function of nucleoplasm?

Q 43.

What is the thickness of cell membrane?

Q 44.

Identify cell organelle and write down its name:
Present in some animal cells, help in locomotion.

Q 45.

Identify cell organelle and write down its name:
Detoxify drugs and poisons specially in liver cells.

Q 46.

Give an example of cells containing two nuclei (Binucleate).

Q 47.

Define Osmosis. What are different types of osmosis? Give examples of osmosis.

Q 48.

Who discovered Golgi apparatus?

Q 49.

What are the components nucleus?

Q 50.

Name the cell organelles which change energy from one form to another.