Cytology244First Term of year

1432-1433Dr.Manal Farhoud -Nuha AL-Abdulhadi

lab 1

The compound Microscope:

The compound light microscope is one of the most important instrument used in zoology.

The applications of

the microscope :

1- It is used to study cells & cell parts

2- It is used to study the organization of tissues

& the structure of developing

embryos .

- How to maintain the microscope:

1- Always carry your microscope with both hands. 2- Grasp the arm of the microscope firmly with one hand and support the base with the other hand.

3- Place it gently on your desk with the arm facing you. 4- Always remember that this expensive scientific instrument is assigned to you for your use and safe – keeping

5-Notify your laboratory instructor if you observe any malfunction or if you have any difficulty in the use of your microscope

*The parts of the microscope can be grouped in three system :

1- The mounting and movement system2- The magnification system 3- The illumination system

1.The mounting and movement system :

1- The base : It is the supporting stand. 2- The arm : It is support the upper part of the microscope. 3- The stage : * It is used to hold the slide .

* Some microscopes are provided with clips to hold the

slide.

1

3

2

>>The mounting and movement system :

.4-The coarse focusing

knob : Its used to raise and lower

the stage. 5- The fine focusing knob : Its used of the purpose of

focusing for the sharpest image.

6.The body tube :Its consist of the ocular

lens at the end and the objective lenses at the other end.

5

6

4

2.The magnification system :

1. The principle purpose of a microscope is to magnify

the image of the objects .

2.The magnification of an object is determined by multiplying the power of the objective lens by the power of the ocular lens.

* Example :10x ocular 10x objective =100x total

magnification bjective + 400x total magnification

3.The illumination system :

1.The illuminator :It’s the source of the light .

2.The condenser : It’s collected and concentrate

the light that passes through the aperture in the stage towards the slide.

3.The iris diaphragm : It’s controlling the amount of

the light to be passed through the lenses.

1

23

NUHA