B1 Cell structure and transport 1 Flashcards
How do we calculate the total magnification of a microscope?
Eyepiece lens x Objective lens magnifying power
State the equation that links magnification, image size and actual size.
Image Size = Actual Size x Magnification
Define ‘resolution’.
The ability to distinguish between two separate points that are very close together
Which type of microscope has higher magnification and resolving power - Light or electron?
Electron microscopes
Why does the tissue sample need to be stained before looking at it under the microscope?
To visualise/see structures clearly
Which objective lens should we start using?
Low power objective lens
Which focus knob should be used during low and medium power magnification?
Coarse focus knob
Which focus knob should be used during high power magnification?
Fine focus knob
Why must we not use the coarse focus knob during high power magnification?
It moves the stage by too much, may break the lens and the slide
What is the function of a scale bar?
To allow us to calculate the actual size of the sample using I=AM
State the function of the nucleus.
Controls all activities of the cell, contains genetic information
State the function of the cytoplasm.
Site for chemical reactions to take place
State the function of the cell membrane.
Controls what substances go in and out of the cell
State the function of the mitochondria.
Site of aerobic respiration, releasing energy
State the function of the ribosomes.
Site of protein synthesis
