microscopy

Question 1

use of laser scanning confocal microscope

Answer 1

It can be used with living cells / thick samples; [1 mark]
It has a high resolution; [1 mark]
It allows the investigator to see the distribution of molecules within cells; [1 mark]
You can control the depth of field; [1 mark]
It provides a sharper / less blurred image
can produce 3D images

Question 2

when to use differential staining

Answer 2

used for light microscopy as the dyes will absorb some colours of light, while reflecting others, making the structures in the specimen visible.

Question 3

centrioles

Answer 3

fibres made of microtubules
Two centrioles at right angles to each other form a centrosome, which organises the spindle fibres during cell division
Not found in flowering plants and fungi

Question 4

microtubules

Answer 4

made of α and β tubulin combined
only in eukaryotic cells
Organelles and other cell contents are moved along these fibres using ATP to drive this movement

Question 5

cytoskeleton use

Answer 5

provide strength and support (scaffolding holds cell shape)
intracellular movement (organelles can move through cell on tracks by motor proteins)
cellular movement (cilia and flagella)

Question 6

cilia

Answer 6

Hair-like projections made from microtubules
Allows the movement of substances over the cell surface

Question 7

flagella

Answer 7

Similar in structure to cilia, made of longer microtubules
Contract to provide cell movement for example in sperm cells

Question 8

micro filaments

Answer 8

made of actin
These fibres can cause some cell movement
the movement of some organelles within cells by moving against each other

Question 9

intermediate filaments

Question 10

unique to prokaryotic

Answer 10

slime capsule
plasmid
70 s ribosomes
no membrane bound organnels
peptidoglycan and murrain cell wall

Question 11

all plant cells contain chloroplasts?

Answer 11

not all e.g. root cells

Question 12

Golgi apparatus use

Answer 12

modify protein/lipid
package protein/lipid
produce vesicle

Question 13

psydepodia

Answer 13

projection used for movement e.g. neutrophils to move to site of infection

Question 14

flagella in prokaryotes structure

Answer 14

not 9 and 2 structure of microtubules (it is in eukaryoted)

Question 15

light microscope

Answer 15

alive specimen
light so can see colour/stain
cannot see small organelle e.g. ribosome
magnification- up to x1500
resolution-200 nm

Question 16

TEM

Answer 16

dead specimen
no colour
see internal structure of organelle, small organelle
(higher resolution) 0.5nm

Question 17

SEM

Answer 17

3D structure (surface0
dead
no colour
(lower resolution) 3-10nm
over x 500,000

Question 18

Laser scanning confocal microscopes

Answer 18

must be dyed with fluorescent dye
see external and 3D structure

Question 19

different lenses in microscope

Answer 19

eye piece lens, then objective lens

Question 20

microvilli vs cilia

Answer 20

Question 21

type of vesicle that contains hydrolytic enzymes

Answer 21

lysosome