Cell: Unit Of Life Flashcards
What is a cell?
A cell is a structural and functional unit of all living beings
The first microscope was created by?
Antony Van Leeuwenhoek
Simple microscopes consisted?
Single Biconvex lens
Who created a microscope with 2 lenses?
Robert Hooke
State the 3 main points of cell theory.
1.The cell is the smallest unit of structure of all living things
2. The cell is the unit of function of all living things
3. All cells arise from pre-existing cells.
Name some single-celled organisms
Bacteria , Amoeba, Yeast
Name some few-celled organisms
Spirogyra, Volvox
Name some multi-celled organisms
Human beings, Mango
The smallest cell
Bacteria, RBC
Longest cells
Nerve cells
Largest cells
Bird’s eggs, ostrich eggs
Why are cells small in size?
- different regions can communicate with each other rapidly for the cell to function effectively
- Cells have large surface area/volume ratio for greater diffusion of substances in and out of the cell.
Shape of Human RBC
circular and biconcave( to pass through narrow capillaries and transport o2)
Shape of WBC
Amoeboid(squeeze out through capillary walls)
Shape of Nerve cells
long(to conduct impulses)