AQA biology 3.1 study of cells

Question 1

Which lens can be used as magnifying glass

Answer 1

Convex lens

Question 2

What is the maxium resolution of an optical light microscope

Answer 2

0.2 mm

Question 3

How can we overcome the limitation of the resolution

Answer 3

Using a beam of electrons

Question 4

Whats difference betwen the beam of electron and beam of light ?

Answer 4

A beam of electron have a shorter wavelenth

Question 5

What is the maxium resolution of an electron microscope

Answer 5

01.nm

Question 6

Material put under microscope = object
Material viewed under microscope = image Type ok

Answer 6

ok

Question 7

What is the equation of magnifacation

Answer 7

size of image / size of real object

Question 8

1mm equal to howe many nm

Answer 8

1000000 nm

Question 9

If the size of image is 10mm and size of real object is 100nm , how many times does magnification occured

Answer 9

x100000 times

Question 10

Greater resolution means ?

Answer 10

Greater clarity

Question 11

Define Cell fractionation

Answer 11

Cell fractionation is the process where cells broken up and the different organelles contain are separated

Question 12

Following is the process of cell fractionation

Answer 12

ok

Question 13

Step 1

Answer 13

Tissue is placed in a cold , buffered solution of the same water potential as the tissue

Question 14

Step 2 homogenation

Answer 14

Cells broke up by a homogeniser to release the organelles

Question 15

Step 3

Answer 15

The fluid homogenate is then filtered to remove any large pieces of debris

Question 16

Step 4 Ultracentrifugation

Answer 16

The tube of filtrate is placed in the centrifuge and spun at a low speed

Question 17

Step 5

Answer 17

The heaviest organelles, the nuclei, are forced to the bottom of the

lube, where they form a thin sediment or pellet

Question 18

Step 6

Answer 18

The fluid at the top of the tube (supernatant) is removed, leaving

Just the sediment of nuclei

Question 19

Step 7

Answer 19

The supernatant is transferred lo another tube and spun in the centrifuge at a faster speed than before.

Question 20

Step 8

Answer 20

The next heaviest organelles, the mitochondria, are forced to the
bottom of the tube

Question 21

Final mention ( watch it)

Answer 21

The next heaviest organelles, the mitochondria, are forced to the
bottom of the tube