More microscopy - 2.3 (5)

Question 1

What does AFM stand for?

Answer 1

atomic force microscope

Question 2

What does the atomic force microscope do?

Answer 2

gathers information about a specimen by ‘feeling’ its surface with a mechanical probe

Question 3

What type of microscopes are AFM and what do they generate?

Answer 3

scanning microscopes that generate three-dimensional images of surfaces

Question 4

What does an AFM consist of?

Answer 4

a sharp tip (probe) on a cantilever

Question 5

What is a cantilever?

Answer 5

a lever supported at one end

Question 6

What is the purpose of the sharp tip used for?

Answer 6

scan the surface of the specimen

Question 7

When the sharp tip is brought very close to a surface, what happens?

Answer 7

forces between the tip and the specimen cause deflections of the cantilever

Question 8

How are these deflections measured?

Answer 8

using a laser beam reflected from the top of the cantilever into a detector

Question 9

What is not required?

Answer 9

fixation and staining

Question 10

In what conditions can specimens be viewed?

Answer 10

almost normal cell conditions

Question 11

When specimens are being viewed, can damage be caused?

Answer 11

no - unlike the damage caused during the preparation of specimens for electron microscopy

Question 12

What can be examined?

Answer 12

living systems

Question 13

What is the resolution of AFM and is it high or low?

Answer 13

it is very high and has a resolution of 0.1nm

Question 14

How can information be gained?

Answer 14

at the atomic level, even about the bonds within molecules

Question 15

What do pharmaceutical industry use AFM for?

Answer 15

to identify potential drug targets on cellular proteins and DNA

Question 16

What can these microscopes lead to a better understanding of?

Answer 16

how drugs interact with their target molecule or cell

Question 17

What is AFM also being used for?

Answer 17

to identify new drugs

Question 18

Finding and identifying new chemical compounds from the natural world takes a…

Answer 18

long time and is expensive

Question 19

The molecular structures need to be understood before…

Answer 19

their potential use in medicine is known

Question 20

What can speed up the process in understanding molecular structures?

Answer 20

atomic force microscopes

Question 21

Can atomic force microscope save money and potentially lives?

Answer 21

yes

Question 22

What case study is a good example of the importance of AFM?

Answer 22

Deep sea molecules

Question 23

Case study - In 2010, what type of species did scientists work on?

Answer 23

bacterium from a mud sample

Question 24

Case study - Where was this mud sample taken from?

Answer 24

the Mariana Trench - the deepest place on the planet

Question 25

Case study - Where is the Mariana Trench located?

Answer 25

nearly 11 000 metres beneath the pacific ocean

Question 26

Case study - What did scientists find?

Answer 26

that the bacteria produced an unknown chemical compound

Question 27

Case study - What was easily determined?

Answer 27

the chemical composition (the number and type of atoms present)

Question 28

Case study - With the use of atomic force microscopy, what were the scientists able to do?

Answer 28

they were able to image the molecules at very high, atomic level resolution within one week

Question 29

Case study - What did AFM give scientists?

Answer 29

the molecular structure they needed to know

Question 30

Case study - Is this the first time AFM had been used in this way?

Answer 30

yes

Question 31

Case study - What could AFM lead to?

Answer 31

a faster identification of unknown compounds

Question 32

Case study - What can AFM speed up?

Answer 32

the process of the development of new medicines