Question:
What is diffusion?
Answer:
Diffusion is the net movement of molecules from high to regions of lower concentration as a result of random molecular motion. Diffusion tends to distribute molecules uniformly. Exchange of gases like CO2 and O2 in lungs, plants, blood cells, O2 entering stomata of leaves are examples of diffusion. Diffusion is passive transport i.e. no external energy is provided for the movement of molecules. The natural kinetic energy of the particle supplies the energy.
The Fundamental Unit of Life
Q 1.
Who proposed fluid-mosaic model of cell or plasma membrane?
Q 2.
Name the biggest cell in human body.
Q 3.
What are chromosomes?
Q 4.
Identify cell organelle and write down its name:
Present in some animal cells, help in locomotion.
Q 5.
Who expanded cell theory by suggesting that all cells arise from pre-existing cells?
Q 6.
What are the components nucleus?
Q 7.
Name the cell organelles which their own DNA and Ribosomes.
Q 8.
When chromosomes are visible in the nucleus?
Q 9.
What is osmoregulation?
Q 10.
Identify cell organelle and write down its name:
A fluid-filled space surrounded by a membrane. Generally contains salts and sugars in plants.
Q 11.
What is the full form of DNA and RNA?
Q 12.
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 14.
Who discovered Virus?
Q 15.
Name the cell type that have internal membranes which compartmentalize their functions.
Q 17.
Who is known as Father of Biology?
Q 18.
Identify cell organelle and write down its name:
Powehouse of cell
Q 19.
Who coined the term 'protoplasm'?
Q 20.
What are centrosomes? What functions do they perform?
Q 21.
What is the function of nucleoplasm?
Q 22.
Identify cell organelle and write down its name:
Called 'suicide bags' of a cell.
Q 23.
Why is mitochondria absent in red blood cells?
Q 24.
Identify cell organelle and write down its name:
A structure involved in production of ribosomes, present inside a nucleus.
Q 25.
Identify cell organelle and write down its name:
Detoxify drugs and poisons specially in liver cells.
Q 26.
Name the longest cell in human body.
Q 27.
Which organelle of the cell in animals helps in osmregulation?
Q 28.
What are the function of nucleus?
Q 29.
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 30.
Name the smallest cell in human body.
Q 31.
Give examples of cells which are muti-nucleate (i.e. having many nuclei).
Q 32.
Will the temperature have any effect on the process of the osmosis?
Q 33.
Name the cell organelles which change energy from one form to another.
Q 34.
Identify cell organelle and write down its name:
Digestive organelle where macromolecules are hydrolyzed
Q 35.
What will happen if a de-shelled egg in a concentrated salt solution for 5 minutes?
Q 36.
Which cell organelle is known as 'protein factory'?
Q 37.
Are Viruses Prokaryotic or Eukaryotic?
Q 38.
Which cell organelle is called 'transport system'?
Q 39.
Are there any exceptions to cell theory proposed by Schleiden & Schwann and Virchow? If yes, what are those?
Q 40.
What is cytoskeleton?
Q 41.
In which year electron microscope was invented?
Q 42.
Name the two postulates of the cell theory.
Q 43.
Name the largest cell?
Q 44.
Is plasma membrane permeable or selectively permeable?
Q 45.
What are different types transport of components across cell membrane?
Q 46.
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 47.
What do you mean by Endocytosis? How does an Amoeba obtain its food?
Q 48.
Why are lysosomes known as suicide bags?
Q 49.
Which organ of the plant body helps in osmoregulation?
Q 50.
Identify cell organelle and write down its name:
Jelly like substance containing particles and other organelles. What is it?
