Week 3 Microscopy

Question 1

What is the microscope resolution formula/ lens aperture formula?

Answer 1

Dmin= 0.612 x λ/ n x A

Question 2

What is λ measured?

Answer 2

m

Question 3

Label the microscope resolution/ lens aperture formula?

Answer 3

Dmin- Minimum um resolvable distance (m)
n- Reflective index between medium and lowest
A- apature

Question 4

What is meant by the lens aperture?

Answer 4

The amount of light allowed in

Question 5

Explain why some lenses have greater resolving powers?

Answer 5

The greater the angle, the greater the resolving power because you see more, its like taking a photo of my buddy face, zoom out and you’ll see more, soon in and you wont

Question 6

In a microscopes different levels of magnification may read: 10x/0.25 40x.0.65 or 100x/1.25 what does the ‘/0.25’ mean?

Answer 6

Its the numerical aperture

Question 7

What will have a higher Dmin: x10/0.25 or x100/1.25?

Answer 7

The x100 because wavelength will be shorter

Question 8

What are all the different light microscopes?

Answer 8

Compound microscopes, stereo microscopes, inverted microscopes, bright field and dark field, phase contrast, fluorescence confocal (staining is a technique and confocal falls under fluorescence category)

Question 9

In basic what is a stereo microscope and its zoom levels?

Answer 9

Two independent light paths, 50-100x max (3D images such as looking close at a fly)

Question 10

Picture an inverted microscope?

Answer 10

it has the lens you look though in the middle with the camera poking in at the bottom (loos at week 3 microscopy page 16 to see pic)

Question 11

In basic how does a bright field microscope work?

Answer 11

The most basic microscope which uses bright background of light to see

Question 12

What’s a benefit and limitation to staining a specimen?

Answer 12

Benefit is the specialised stain can react with molecules, giving a colour and a limitation is the specimen usually have to be dead

Question 13

What type of specimen would phase contract be aimed at?

Answer 13

A transparent specimen

Question 14

Explain the difference between SEM and TEM?

Answer 14

SEM is used to create 3d images, low magnification and can view intact structures and minimum specimen preparation, TEM has high magnification but can only look at 2d images and can be used to look at speicific large molecules and lots of specimen preperation

Question 15

In basic, how does fluorescence work?

Answer 15

Fluorophores contain chemicals. Fluorophores absorb light at one wavelength and distribute it at a different wavelength

Question 16

When looking through a microscope, explain how would you distinguish neutrophils?

Answer 16

The nucleus is multi-lobed and held together by thin threads

Question 17

When looking through a microscope, explain how would you distinguish monocytes?

Answer 17

The nucleus look of that a kidney

Question 18

What is the largest white blood cell?

Answer 18

Monocytes

Question 19

When looking through a microscope, explain how would you distinguish lymphocytes?

Answer 19

Because the nucleus tends to be circular