Microscopes

Max resolution of a light microscope

200nm

max magnification of light microscope

x1500

What is not visible with a light microscope

ribosomes

What does a light microscope show

whole cells, nuclease and chlorplasts

type of images made by light microscopes

2D coloured images

max resolution of confocal microscope

200nm

max magnification of confocal microscope

x1500

what type of image is produced by a confocal scanning microscope

2D/3D images that are fluroesccentlly coloured

max resolution of scanning electron

3-10nm

max mag of scanning electron

x100,000

What images does a scanning electron microscope produce

2D black and white section view images

what can be seen with a SEM

cillia and bacterial cell wall

max resoltuion of transmission electron

0.5nm

what type of images does TEM produce

2D black and white images of thin sections where mebranes and ribosmes are visible

wet mound technique

Suspend the specimen in liquid like water or immersion oil and place a cover slip ontop from an angle

Dry mound technique

section the specimen if too large, place the specimen on the centre of the slide and place a cover slip on top

Squash mound technique

Prepare a wet mound and then use a lens tissue to press down on the cover slip

uses of squash mound technique

view root tips during cell division

Blood smear mound technique

Use a pippete to place blood near one end of the slide and then use a cover slip at an angle to smear the blood across the slide

Biological drawings rules

lable lines should not cross, no arrowheads, give a title, no shading, state magnification and draw organelles in proportion

Correct staning techniques

Place the stain at the edge of the sample, hold the cover slip at approcimatley 45 degrees, place blotting paper on the opposite side of the cover slide to remove excess stain and use more than one stain to improve contrast

resolution

ability to distinguish between two seperate points

magnification

how much larger the image appears compared to the actual size

magnification formula

image/actual