RPA 1-Using a light microscope

Question 1

Name different parts of a microscope?

Answer 1

• eyepiece lens(x10)
• objective lens(x5, x10, x40)
• Stage
• Light
• Coarse focus knob
• Fine focus knob

Question 2

How do you draw a specimen?

Answer 2

• Title
• Sharpe pencil
• Detailed labels
• Horizontal label lines
• No shading
• No overlapping of lines
• Magnification noted-At least 1/3 the page big

Question 3

What is the triangle that links image size, actual size and magnification?

Answer 3

I
   A M
I-image size
A-actual size
M-magnification

Question 4

A microscope has a x5 eyepiece lens.

Describe how to use a microscope to observe a prepared slide of root hair cells at a magnification of x50.

Answer 4

• place slide on stage
• use lowest power objective lens initially
• switch light on so light passes through slide
• move stage as close to lens as possible
• slide must not touch lens
• turn focussing knob so slide moves away from lens
• turn focussing knob until image comes into focus
• use fine focus to get clear image
• change objective lens to x10
• x5 eyepiece and x10 objective lenses (give total magnification of x50)
• refocus slide using focussing knob