Biology experiments Flashcards
(134 cards)
1
Q
Test for starch
chemical used
A
iodine
2
Q
Test for starch
initial colour
A
yellow/red
3
Q
Test for starch
final colour
A
blue/black
4
Q
Test for starch
how do you add iodine
A
with a dropper
5
Q
Test for starch
what do you test
A
bread
6
Q
Test for starch
what is the control
A
water
7
Q
Test for starch
colour change in control
A
stays red/yellow the whole time
8
Q
Test for reducing sugar
chemical used
A
Benedicts solution
9
Q
Test for reducing sugar
what do we test
A
glucose syrup
10
Q
Test for reducing sugar
initial colour of BS
A
blue
11
Q
Test for reducing sugar
final colour of bs
A
orange/brick red
12
Q
Test for reducing sugar
describe set up
A
equal amounts of substance and benedicts solution in a test tube
13
Q
Test for reducing sugar
where does the test tube go?
A
in a water bath and heated gently
14
Q
Test for reducing sugar
control
A
water
15
Q
Test for reducing sugar
colour change in control
A
stays blue
16
Q
Test for soluble protein
Name of test
A
biuret test
17
Q
Test for soluble protein
what do we test
A
milk
18
Q
Test for soluble protein
chemicals used
A
sodium hydroxide and copper sulphate
19
Q
Test for soluble protein
what colour is sodium hydroxide
A
colourless
20
Q
Test for soluble protein
what colour is copper sulphate
A
blue
21
Q
Test for soluble protein
describe the setup
A
milk in a test tube with sodium hydroxide and a few drops of copper sulphate added in
22
Q
Test for soluble protein
control
A
water
23
Q
Test for soluble protein
final colour
A
purple
24
Q
Test for soluble protein
colour change for control
A
stays blue
25
Test for Fat
| describe experiment
rub fat on a piece of brown paper
26
Test for fat
| what do we test
butter
27
Test for fat
| control
water
28
Test for fat
| change
a translucent stain appears and remains after drying
29
Test for fat
| change in control
spot dries up after a day
30
MICROSCOPE
| eyepiece magnification
x10
31
MICROSCOPE
| objective lens magnification
x4, x10, x40
32
MICROSCOPE
| what do you use coarse focus wheel with
with the low power lens
33
MICROSCOPE
| what do you use the fine focus wheel with
high power lens
34
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MICROSCOPE
function of the focus wheels
```
focus the specimen
35
MICROSCOPE
| stage
slide is placed here
36
MICROSCOPE
| condenser/iris diaphragm
controls amount of light going onto the specimen
37
MICROSCOPE
| lamp or mirror
shines light through the specimen
38
OBSERVING ANIMAL CELLS
| how do you obtain the animal cells
using a clean cotton bud, remove a sample of chec cells from inside the mouth
39
OBSERVING ANIMAL CELLS
| where do the animal cells go
place them on a slide
40
OBSERVING ANIMAL CELLS
| 2 things you could add to the slide
water
| methylene blue
41
OBSERVING ANIMAL CELLS
| to stain cells
methylene blue
42
OBSERVING ANIMAL CELLS
| unstained cells
water
43
OBSERVING ANIMAL CELLS
| how do you add the cover slip and why
place down from an angle of 45º to eliminate air bubbles
44
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OBSERVING ANIMAL CELLS
function of cover slip 2
```
protects specimen from drying out
| protects the lenses
45
OBSERVING ANIMAL CELLS
| what do you do before setting it up on the stage
dry excess fluid on the slide
46
OBSERVING ANIMAL CELLS
| how do you secure the slide on the stage
clip it into position
47
OBSERVING ANIMAL CELLS
| how do you locate suitable cells
using the low power objective lens
48
OBSERVING ANIMAL CELLS
| how do you focus at the start
using the coarse focus wheel
49
OBSERVING ANIMAL CELLS
| after you have located suitable cells
use a high power objective lens
50
OBSERVING ANIMAL CELLS
| how do you focus using a high power objective lens
fine focus knob
51
OBSERVING ANIMAL CELLS
| why do you only use a fine focus knob when using a high powered lens
the prevent damage to slide and lens
52
OBSERVING ANIMAL CELLS
| how do you record the experiment
draw cells at high and low power
53
OBSERVING ANIMAL CELLS
| how do you know where the nucleus is
the methylene blue stains the nucleus darker blue than the rest of the cells
54
OBSERVING PLANT CELLS
| how do you obtain the cells?
using a scalpel, remove a thin piece of onion skin
55
OBSERVING PLANT CELLS
| how do you know if the piece is thin enough
you should be able to see light through it
56
OBSERVING PLANT CELLS
| why do we want the piece to be so thin
so that individual cells can be seen
57
OBSERVING PLANT CELLS
| what do you add to cell for unstained cell
drop of water
58
OBSERVING PLANT CELLS
| what do you add to cell for a stained cell
drop of iodine
59
OBSERVING PLANT CELLS
| where do you put the onion cells
on a glass slide
60
OBSERVING PLANT CELLS
| how do you put on the cover slip and why
add at an angle of 45º to prevent air bubbles
61
OBSERVING PLANT CELLS
| before putting slide on the stage
dry any excess fluid from it
62
OBSERVING PLANT CELLS
| how do you tell where the nucleus is?
iodine stains the nucleus darker than the rest of the cells
63
TRANSVERSE SECTION OF A DICOT STEM
| describe the stem you use
a young wet privet stem
64
TRANSVERSE SECTION OF A DICOT STEM
| why does it need to be young
so that the vascular bundles can be easily seen
65
TRANSVERSE SECTION OF A DICOT STEM
| why does it have to be wet
so that it is easy to cut thin sections of the stem
66
TRANSVERSE SECTION OF A DICOT STEM
| how do you cut up the stem
support the stem with your hand, place the stem on a chopping board and use a scalpel to cut thin transverse sections of the stem
67
TRANSVERSE SECTION OF A DICOT STEM
| where do you put the thin pieces of the stem and why
transfer them to a dish of water to keep them moist
68
TRANSVERSE SECTION OF A DICOT STEM
| how do you choose which pieces to use
choose the thinnest pieces
69
TRANSVERSE SECTION OF A DICOT STEM
| how do you transfer the thinnest pieces onto a slide
using a paintbrush
70
TRANSVERSE SECTION OF A DICOT STEM
| what do you put on the slide 2
water for stained or iodine for unstained
71
TRANSVERSE SECTION OF A DICOT STEM
| how do you record the experiment
draw the best section under low and high power
72
TO DEMONSTRATE OSMOSIS
| what do you do first
cut a section of visking tube and soak it in water to soften it
73
TO DEMONSTRATE OSMOSIS
| what is visking tube
an artificial semi permeable membrane
74
TO DEMONSTRATE OSMOSIS
| what do you do at one end of the tubing
tie a knot
75
TO DEMONSTRATE OSMOSIS
| what do you fill the tubing with
a starch solution
76
TO DEMONSTRATE OSMOSIS
| after you fill with a starch solution
tie a knot at the other end of the tubing
77
TO DEMONSTRATE OSMOSIS
| what do you do to the bag then 2
dry the outside of the bag and weigh the bag
78
TO DEMONSTRATE OSMOSIS
| where do you suspend the bag
in a beaker of water
79
TO DEMONSTRATE OSMOSIS
| how long do you leave the bag for
about 15 minutes
80
TO DEMONSTRATE OSMOSIS
| how do you find the results
dry the outside of the bag and reweigh it
81
TO DEMONSTRATE OSMOSIS
| what would be the control
the same thing but with water instead of starch solution
82
TO DEMONSTRATE OSMOSIS
| result for starch
weighs more at the end, it swelled
83
TO DEMONSTRATE OSMOSIS
| why does the visking tubing weigh more at the end
water has entered the visking tubing bag by osmosis from a solution with more water to a solution with less water
84
TO DEMONSTRATE OSMOSIS
| change in control
no change
85
equation for demonstrating how catalase works
hydrogen peroxide --(catalase)---> water and oxygen
86
EFFECT OF TEMPERATURE ON THE RATE OF ENZYME ACTION
| how do you keep pH constant
add pH buffer 9 into the graduated cylinder
87
EFFECT OF TEMPERATURE ON THE RATE OF ENZYME ACTION
| what do you add to graduated cylinder
a drop of washing up liquid
88
EFFECT OF TEMPERATURE ON THE RATE OF ENZYME ACTION
| what is the function of the washing up liquid
allows the foam to form as oxygen is a product of the reaction
89
EFFECT OF TEMPERATURE ON THE RATE OF ENZYME ACTION
| what enzyme do we use
catalase
90
EFFECT OF TEMPERATURE ON THE RATE OF ENZYME ACTION
| what is the source of catalase
we add fresh chopped celery into the graduated cylinder which is the source of catalase
91
EFFECT OF TEMPERATURE ON THE RATE OF ENZYME ACTION
| what is the substrate
hydrogen peroxide
92
EFFECT OF TEMPERATURE ON THE RATE OF ENZYME ACTION
| how do we get the hydrogen peroxide
drop some hydrogen peroxide into the test tube
93
EFFECT OF TEMPERATURE ON THE RATE OF ENZYME ACTION
| where do you first put the graduated cylinder and test tube
in a water bath at 0ºc
94
EFFECT OF TEMPERATURE ON THE RATE OF ENZYME ACTION
| after is it in a water bath at 0ºc
add in some hydrogen peroxide and stir gently
95
EFFECT OF TEMPERATURE ON THE RATE OF ENZYME ACTION
| how do you find the rate of enzyme action
measure the height of foam produced per minute
96
EFFECT OF TEMPERATURE ON THE RATE OF ENZYME ACTION
| why do you repeat the experiment
repeat at different temperatures to get more results
97
EFFECT OF TEMPERATURE ON THE RATE OF ENZYME ACTION
| how do you calculate results
draw a graph
98
EFFECT OF pH ON THE RATE OF ENZYME ACTION
| how do you keep the temperature constant
put in a water bath at 25ºc
99
EFFECT OF TEMPERATURE ON THE RATE OF ENZYME ACTION
| how do you change the pH
add different pH buffers each time, eg. pH 2, pH 4 etc.
100
THE EFFECT OF HEAT DENATURING ON THE RATE OF ENZYME ACTION
| what do you place in both graduated cylinders
pH buffer 9 and washing up liquid
101
EFFECT OF DENATURING ON THE RATE OF ENZYME ACTION
| what do you put only in the graduated cylinder in the real experiment
chopped boiled celery
102
EFFECT OF DENATURING ON THE RATE OF ENZYME ACTION
| what do you put only in the graduated cylinder in the control experiment
chopped fresh celery
103
EFFECT OF DENATURING ON THE RATE OF ENZYME ACTION
| what does boiling the celery do?
denatures the enzyme catalase in the celery
104
EFFECT OF DENATURING ON THE RATE OF ENZYME ACTION
| what do you put in both test tubes
hydrogen peroxide
105
EFFECT OF DENATURING ON THE RATE OF ENZYME ACTION
| where do you put all the apparatus for both experiments
into a water bath at 25ºc
106
EFFECT OF DENATURING ON THE RATE OF ENZYME ACTION
| how do you start the reaction
pour some of the hydrogen peroxide from each test tube into each graduated cylinder
107
EFFECT OF DENATURING ON THE RATE OF ENZYME ACTION
| before you add in the hydrogen peroxide
allow some time to reach 25ºC
108
EFFECT OF DENATURINGE ON THE RATE OF ENZYME ACTION
| how do you calculate the results
measure the height of foam produced per minute using a stop watch
109
EFFECT OF DENATURING ON THE RATE OF ENZYME ACTION
| result from the real experiment
no foam produced as the catalase was denatured
110
EFFECT OF DENATURING ON THE RATE OF ENZYME ACTION
| result from control experiment
foam was produced
111
THE PREPARATION OF AN IMMOBILISED ENZYME
| the first thing you have to do
prepare a solution of sodium alginate
112
THE PREPARATION OF AN IMMOBILISED ENZYME
| what is sodium alginate
the gel that traps the enzyme
113
THE PREPARATION OF AN IMMOBILISED ENZYME
| what do you add to the sodium alginate
add yeast
114
THE PREPARATION OF AN IMMOBILISED ENZYME
| why do we add yeast
it is the source of the enzyme
115
THE PREPARATION OF AN IMMOBILISED ENZYME
| what do you do with the enzyme solution
take it into a syringe and drop into a beaker of calcium chloride to allow beads to form
116
THE PREPARATION OF AN IMMOBILISED ENZYME
| what happens when the beads are formed
the sodium and calcium swap places and hard beads of calcium alginate are formed around the yeast cells
117
THE PREPARATION OF AN IMMOBILISED ENZYME
| after the beads are formed
allow to stand for 5 minutes to allow time for the beads to form
118
THE PREPARATION OF AN IMMOBILISED ENZYME
| how do you remove debris
filter the mixture
119
THE PREPARATION OF AN IMMOBILISED ENZYME
| how do you remove any surface yeast
wash the beads
120
THE USE OF AN IMMOBILISED ENZYME
| what do you put in the 2 funnels
A: Beads of immobilised yeast
B: free yeast and water
121
THE USE OF AN IMMOBILISED ENZYME
| what is free yeast
yeast and water
122
THE USE OF AN IMMOBILISED ENZYME
| what do you add to each funnel then
sucrose
123
THE USE OF AN IMMOBILISED ENZYME
| why do you add sucrose
it is the substrate for the enzyme in yeast
124
THE USE OF AN IMMOBILISED ENZYME
| how do you collect the product
open the taps and collect the product in beakers
125
THE USE OF AN IMMOBILISED ENZYME
| what do you note in the beakers
note if they are cloudy or clear
126
THE USE OF AN IMMOBILISED ENZYME
| what do you test for in each solution
reducing sugar
127
THE USE OF AN IMMOBILISED ENZYME
| how do you test for reducing sure
using Benedict's solution
128
THE USE OF AN IMMOBILISED ENZYME
| which is cloudy, the product from immobilised or free?
the product from the free yeast is cloudy
129
THE USE OF AN IMMOBILISED ENZYME
| what does it mean that its clear
no enzyme mixed with the product
130
THE USE OF AN IMMOBILISED ENZYME
| what does it mean that it is cloudy
enzyme is mixed with the product
131
THE USE OF AN IMMOBILISED ENZYME
| which one tests positively for reducing sugar
both
132
THE USE OF AN IMMOBILISED ENZYME
| is sucrose a reducing sugar
no
133
THE USE OF AN IMMOBILISED ENZYME
| how is a reducing sugar present in the product
the enzyme in the yeast has converted the sucrose into a reducing sugar
134
THE USE OF AN IMMOBILISED ENZYME
| 2 advantages of an immobilised enzyme
- enzyme can easily be recovered and reused
| - the product is pure
