Question

Tgan sy organs of each syster, laver image, or a dissection ch organ when presented ther Pre-Lab als > Practice Anatomy Lab endels Review Sheet 3 35 -5. Why should the light be dimmed when looking at living (nearly transparent) cells? 6. If, after focusing in low power, you need to use only the fine adjustment to focus the specimen at the higher powers, the microscope is said to be - 7. You are using a 10x ocular and a 15x objective, and the field diameter is 1.5 mm. The ap- proximate field size with a 30x objective is _ _mm. 8. If the diameter of the low-power field is 1.5 mm, an object that occupies approximately a third of that field has an estimated diameter of mm.

Answer 1

Ans 5. When looking at nearly transparent living cell the light is dimmed because this increases the contrast which makes easier to see the cell. If the light have been bright it would shine through the transparent cell making it difficult to observe the cell.

Ans 6. Parfocal.

Ans7. 0.75mm

Calculation: diameter of fov 2 = diameter of fov 1 x magnification1 divided by magnification 2 (fov is feild of view)

Diameter 2 = 1.5mm × 15/ 30 = 0.75 mm

Ans8. 0.5mm

Calculations : diameter of fov 2 = diameter of fov 1 × magnification 1/ magnification 2

Here diameter of fov 1 = 1.5 mm and magnification 1/magnification 2 = 1/3

So, unknown diameter = 1.5mm × 1/3 = 0.5mm