core practical 5

Question 1

what is the method of using light microscope for liquid specimen

Answer 1

wear gloves to prevent contamination then add a few drops of specimen using pipette the cover with coverslip and press to remove air bubbles

Question 2

what is the method of using light microscope for solid specimen

Answer 2

use scalpel to cut a small sample of the tissue
- use forceps to cut very thin layer to the slide
- add stain to make the cell more visible
- place coverslip to remove air bubbles

Question 3

what is the method of using light microscope for samples that are needed to be treated with chemicals to kill cells or make the tissue rigid

Answer 3

• it involves fixing using preservative formaldehyde, dehydrating it using a series of ethanol solutions and then resin then cut thin slices of specimen and a stain is applied

Question 4

how to use microscope

Answer 4

• Always start with low power objective lens
• prevent the dehydration of tissue
• when the image is unclear or blurred use coarse focus

Question 5

what are the limitation of using a microscope

Answer 5

the microscope only shows a 2D shape of the tissue

Question 6

what is an eyepiece graticule and stage micrometer

Answer 6

• graticule is like a ruler that can be placed in the eyepiece which can be called eyepiece graticule
• An eyepiece graticule has no units so needs to be calibrated with stage micrometer

Question 7

how much µm does 1mm has

Answer 7

1000