Calculating Cell Size/ Osmosis Flashcards
How to calculate actual size of a cell?
Image size/ magnification
Calculate the length of cells in micrometers
If the actual size of a cell is 100 μm, and 10 cm in
a book, what is the magnification of the image in
the book?
Calculating magnification-
Image size/ actual size
First convert 10cm into millimeter by x10. Then convert it from millimeter to micro meter by x1000.
10x10=100 100x1000=
100,000 micrometer
The plant cell contains mitochondria but the bacterial cell
does not contain mitochondria.
Use your answer to part (b)(i) and the information in the
diagram to suggest why.
The mitochondria is the same size as the bacterial cell
Explain water movement in hypertonic, hypotonic, isotonic-
Hypertonic- concentrated solution outside of the cell, so water molecules move outside of the cell.
Hypotonic- dilute solution outside the cell. Water moves inside the cell.
Isotonic- same concentration of solute and solvent inside and outside the cell so there is no net movement of water.
What are the effects of these solutions-
When too much water moves outside the cell, it shrinks and the cytoplasm pulls away from the cell membrane.
When too much water moves inside the cell, it swells and bursts, and becomes turgid.
When there is no met movement of water, the cell remains the same, however it can become flaccid: soft.
What is plasmolysis?
In hypertonic solutions when water leaves the cell, in some situations when too much water leaves the cell, the cytoplasm pulls away from the cell membrane.
