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:
- Cell theory do not explain nature of Virus. They become live and multiply though they are made up of non-living material.
- 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.).
- Mitochondria and chloroplasts have their own genetic material and can reproduce independently.
The Fundamental Unit of Life
Q 1.
Give examples of cells which are muti-nucleate (i.e. having many nuclei).
Q 2.
What is the thickness of cell membrane?
Q 4.
What is the energy currency of the cell called?
Q 5.
What is osmoregulation?
Q 6.
Identify cell organelle and write down its name:
Called 'suicide bags' of a cell.
Q 7.
In which year electron microscope was invented?
Q 8.
What is the full form of DNA and RNA?
Q 9.
What are the conditions for osmosis?
Q 10.
Why are lysosomes known as suicide bags?
Q 11.
Which cell organelle is called 'control center'?
Q 12.
Give an example of anucleate cell i.e. cell without nucleus.
Q 13.
Put dried raisins in plain water and leave them for some time. Then place them in concentrated solution of sugar or salt. What do you observe in both cases?
Q 14.
Name the sac like structure which form the grana?
Q 15.
Will the temperature have any effect on the process of the osmosis?
Q 16.
What is the function of nucleoplasm?
Q 17.
What is plasmolysis?
Q 18.
What will happen if a de-shelled egg in a concentrated salt solution for 5 minutes?
Q 19.
Who is known as Father of Biology?
Q 20.
Who discovered Golgi apparatus?
Q 21.
Who is known as 'Father of Microscopy'?
Q 22.
What are chromosomes?
Q 23.
Name the cell organelles which change energy from one form to another.
Q 24.
Identify cell organelle and write down its name:
Membrane-bound vesicles arranged approximately parallel to each other. Active in synthesis, modification, sorting, and Secretion of cell products
Q 25.
Name the biggest cell in human body.
Q 26.
Define Osmosis. What are different types of osmosis? Give examples of osmosis.
Q 27.
Which organ of the plant body helps in osmoregulation?
Q 28.
Name the cell organelles which their own DNA and Ribosomes.
Q 29.
Identify cell organelle and write down its name:
A structure involved in production of ribosomes, present inside a nucleus.
Q 30.
Who expanded cell theory by suggesting that all cells arise from pre-existing cells?
Q 31.
Who proposed fluid-mosaic model of cell or plasma membrane?
Q 32.
Which organelle of the cell in animals helps in osmregulation?
Q 33.
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 34.
What is cytoskeleton?
Q 35.
Name the cell organelles involved in synthesis, packaging and movement of protein (or other macromolecules) inside a cell.
Q 36.
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 37.
Identify cell organelle and write down its name:
Present in some animal cells, help in locomotion.
Q 38.
Who observed the cells the first time?
Q 39.
Name the two postulates of the cell theory.
Q 40.
Name the smallest cell in human body.
Q 41.
What is the plasma membrane composed of?
Q 42.
Define Passive Transport.
Q 43.
Which cell organelle is known as 'protein factory'?
Q 44.
Which cell organelle is called 'kitchen of plant'?
Q 45.
What are the functions of Endoplasmic Reticulum (ER)?
Q 46.
Who discovered Virus?
Q 47.
Why is mitochondria absent in red blood cells?
Q 48.
Name the cell type that have internal membranes which compartmentalize their functions.
Q 49.
Identify cell organelle and write down its name:
Contains green colour pigment, traps light energy. Present in some plant cells.
Q 50.
Identify cell organelle and write down its name:
A tough, non-living layer, it prevents plant cells from bursting, freely permeable
