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gcse science > Science - Biology - Organisation - Tissues, Organs, and Organ Systems -B2a > Flashcards

Science - Biology - Organisation - Tissues, Organs, and Organ Systems -B2a Flashcards

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1
Q

what are cells ?

A

the basic building blocks of life that make up living organisms

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2
Q

what is differentiation

A

the process by which cells become specialized for a particular job

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3
Q

arrange these in order :
organs
tissues
cells
organ systems

A

cells
tissues
organs
organ system

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4
Q

what is a tissue ?

A

a group of similar cells that work together to carry out a particular function

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5
Q

give an example of a tissue in mammals and it’s function

A

muscular tissue - contracts to move whatever it’s attached to

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6
Q

what is the function of the glandular tissue ?

A

makes and secretes substances like enzymes and hormones

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7
Q

what is the function of the epithelial tissue ?

A

covers some parts of the body e.g the gut

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8
Q

what is an organ ?

A

a group of different tissues that work together to perform a certain function

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9
Q

what tissues is the stomach made out of ?

A

muscular tissue
glandular tissue
epithelial tissue

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10
Q

what is an organ system ?

A

a group of organs working together to perform a particular function

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11
Q

what is the digestive system ?

A

an organ system that breaks food down

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12
Q

what organs is the digestive systems made up of ?

A

glands - pancreas and salivary
stomach
liver
small intestine
large intestine

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13
Q

what happens in the lungs ?

A

gas exchange - oxygen and carbon dioxide

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14
Q

where are the lungs ?

A

in the thorax

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15
Q

what protects the lungs ?

A

the rib cage

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16
Q

explain airs journey to the lungs

A

air you breathe goes through the trachea
splits into tubes called bronchi
the bronchi splits into smaller tubes called bronchioles
the bronchioles end at small bags called alveoli where gas exchange happens

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17
Q

what is the alveoli ?

A

millions of little air sacs where gas exchange happens

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18
Q

why does oxygen and carbon dioxide diffuse in and out of the alveolus ?

A

oxygen diffuses out of the alveolus and into the blood and carbon dioxide diffusers into the alveolus and out of the blood

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19
Q

when blood reaches body cells what does oxygen do ?

A

oxygen is released from the red blood cells and into body cells

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20
Q

what happens to carbon dioxide in the body cells ?

A

it diffuses out of the body cells into the blood and then is carried back to the lungs

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21
Q

what is the calculation for breathing rate ?

A

number of breaths /
number of minutes

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22
Q

amy takes 108 breaths in 9 minutes. what is her average breathing rate per minute ?

A

108/9 = 12 breaths per minute

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23
Q

what is the function of the circulatory system ?

A

to get food and oxygen to every cell in the body

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24
Q

explain the double circulatory system

A
  • in the first circuit the right ventricle pumps deoxygenated blood to the lungs to take in oxygen, the blood then returns to the heart
  • in the second circuit the left ventricle pumps oxygenated blood around all other organs of the body, the blood gives up its oxygen at the body cells and the deoxygenated blood returns to the heart to be pumped out to the lungs again
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25
Q

what is the heart ?

A

a pumping organ that keeps blood flowing around the body

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26
Q

what are the walls of the heart made up of ?

A

muscle tissue, which contracts to pump blood

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27
Q

what are the 4 chambers of the heart ?

A

left atrium
right atrium
left ventricle
right ventricle

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28
Q

what are the main vessels leading out of the chambers ?

A

vena cava
pulmonary artery
pulmonary vein
aorta

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29
Q

what is the function of valves ?

A

to make sure the blood goes in the right direction, prevents it flowing backwards

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30
Q

what do the coronary arteries do ?

A

branch of the aorta and surround the heart to make sure it gets all of the oxygenated blood it needs

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31
Q

explain the blood flow cycle of the heart

A

-blood flows from vena cava and pulmonary vein into the 2 atria
-the atria contract, pushing the blood into the ventricles
-the ventricles contract, forcing the blood into the pulmonary artery and the aorta out of the heart
-the blood then flows to the organs through the arteries and returns through veins
-the atria fill again and cycle repeats

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32
Q

what does an artificial pacemaker do ?

A

controls a heartbeat, if the natural pacemaker cells don’t work properly, it produces an electric current to keep the heart beating regularly

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33
Q

what do arteries do ?

A

carry blood away from the heart, towards the organs

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34
Q

describe artery walls

A

strong, elastic, thick

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35
Q

what are capillaries ?

A

they are involved in the exchange of materials at tissues and supply food and oxygen to the cells and take away waste products like carbon dioxide

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36
Q

how are capillaries adapted to help it’s function ?

A

permeable walls so exchanged substances can easily diffuse in and out
narrow, giving them a large surface area compared to volume ratio giving them an increased rate of diffusion

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37
Q

what do veins do ?

A

carry blood to the heart

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38
Q

how are veins adapted to help it function ?

A

thick lumen to help blood flow

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39
Q

how do you calculate blood flow ?

A

volume of blood /
number of minutes

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40
Q

800 ml of blood passed through an artery in 2 minutes.
calculate blood flow

A

800/2 = 400 ml/min

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41
Q

what is blood ?

A

a tissue that transports substances around the body

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42
Q

what is blood made up of ?

A

red blood cells
white blood cells
platelets
- all of which are suspended in plasma

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43
Q

what do red blood cells do ?

A

transport oxygen around the body

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44
Q

how are red blood cells adapted to its function ?

A

bioncave shape to give a large surface area
contain red pigment called haemoglobin to carry more oxygen
no nucleus so more room for oxygen

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45
Q

what do white blood cells do ?

A

defend against microorganisms that cause disease

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46
Q

how do white blood cells carry out their jobs ?

A

-engulf unwelcome microorganisms in a process called phagocytosis to digest them
- produce antibodies to fight microorganisms
- produce antitoxins to neutralize any toxins produced by microorganisms

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47
Q

what do platelets do ?

A

help blood clot at a wound which stops you losing to much blood and stop’s microorganisms getting in at the wound

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48
Q

what can a lack of platelets lead to ?

A

lots of bleeding and bruising

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49
Q

what does plasma do ?

A

carry everything in the blood, e.g
red blood cells
nutrients
proteins etc

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50
Q

what type of tissues are plant organs made of ?

A
  • epidermal tissue
  • palisade mesophyll
  • spongy mesophyll
  • xylem and phloem
  • meristem tissue
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51
Q

where is the epidermal tissue ?

A

on the entire plant

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52
Q

what happens at the palisade mesophyll tissue ?

A

most of photosynthesis

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53
Q

what is the spongy mesophyll ?

A

contains big air spaces to allow gases to diffuse in and out of cells

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54
Q

what does the xylem and phloem do ?

A

transport things like water, mineral ions, and food around the plant

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55
Q

what is the meristem tissue ?

A

found at the growing tips of shoots and roots and is able to differentiate into lots of different types of plant cells

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56
Q

where is the meristem tissue found ?

A

growing tips of shoots and roots

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57
Q

what are epidermal tissues covered in ?

A

waxy cuticle

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58
Q

what does the waxy cuticle do ?

A

reduce water loss by evaporation

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59
Q

how is the upper epidermis suitable for its job ?

A

it is transparent so light can pass through it to the palisade layer

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60
Q

what does the palisade layer contain ?

A

lots of chloroplasts

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61
Q

why does the palisade layer contain lots of chloroplasts ?

A

so as much photosynthesis can happen as possible - gets the most light

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62
Q

what do the xylem and phloem form ?

A

a network of vascular bundles

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63
Q

what do the vascular bundles of xylem and phloem cells do ?

A
  • deliver water and other nutrients to the entire leaf
  • take away the glucose produced by photosynthesis
  • support the structure
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64
Q

how are the tissues of the leaves adapted to suit its function ?

A
  • suited for good gas exchange
  • lower epidermis is full of little holes
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65
Q

what are stomata ?

A

holes in the lower epidermis which lets CO2 diffuse directly into the leaf

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66
Q

what controls the opening and closing of the stomata ?

A

guard cells

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67
Q

how do the guard cells know when to open and close the stomata ?

A

they respond to environmental conditions

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68
Q

what helps to increase the rate of diffusion of gases in the leafs structure ?

A

air spaces in the spongy mesophyll

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69
Q

what are phloem tubes made up of ?

A

columns of elongated living cells with small pores in the end walls to allow cell sap to flow through

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70
Q

what is cell sap ?

A

a liquid that’s made up of the substances being transported and water

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71
Q

what do phloem tubes do ?

A

transports food substances made in the leaves to the rest of the plant for immediate use or for storage

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72
Q

what direction does the transport for phloem tubes go in ?

A

both directions -
from the leaves down to the roots
from the roots to the leaves

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73
Q

what is translocation ?

A

the movement of dissolved sugars around the plant

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74
Q

what are xylem tubes made of ?

A

dead cells joined end to end with no end walls between them and a hole down the middle

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75
Q

how are xylem tubes strengthened ?

A

by a material called lignin

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76
Q

what do xylem tubes do ?

A

carry water and mineral ions up the plant form the roots to the leaves

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77
Q

what is the transpiration stream ?

A

movement of water from the roots through the xylem and out of the leaves

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78
Q

what is transpiration ?

A

the loss of water from a plant

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79
Q

describe the transpiration stream ?

A

1 - water from inside a leaf evaporates and diffuses out of the leaf, mainly through the stomata

2- this creates a slight shortage of water in the leaf so more water is drawn up from the rest of the plant through the xylem vessels to replace it

3- this in turn means more water is drawn up from the roots so then there’s a constant transpiration stream of water through the plant

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80
Q

what is transpiration a side-effect of ?

A

photosynthesis

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81
Q

what does water escape the leaves through ?

A

the stomata through diffusion

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82
Q

what are the 4 things affected by transpiration rate ?

A
  • light intensity
  • temperature
  • air flow
  • humidity
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83
Q

how is transpiration affected by light intensity ?

A

brighter the light = greater the transpiration rate because the stomata begins to close as it gets darker when the stomata is closed water can’t escape

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84
Q

how is the stomata used in transpiration ?

A

the stomata which is also used for gas exchange helps to get rid of water from transpiration through diffusion

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85
Q

how does temperature affect transpiration ?

A

the warmer it is the faster transpiration happens because when it is warm particles have more energy to evaporate and diffuse out of the stomata

86
Q

how does air flow affect transpiration ?

A
  • the better air flow, the greater the greater the transpiration rate
  • if there is good air flow water vapour is swept away maintaining a low concentration of water in the air outside the leaf as diffusion happens quickly from an area of high to low concentration
87
Q

how does humidity affect transpiration ?

A
  • the drier the air around the leaf the faster transpiration happens
  • diffusion happens fastest if there is a really high concentration in one place and a really low concentration in the other
88
Q

how do you investigate transpiration rate ?

A
  • measure the uptake of water by a plant
89
Q

why can you investigate transpiration rate ?

A

you can assume that water uptake by the plant is directly related to water loss by the leaves

90
Q

describe how to investigate transpiration rate ?

A

record the starting position of the air bubble
start a stopwatch
record the distance moved by the bubble per unit of time

91
Q

what do you need to keep the same when investigating the rate of transpiration ?

A

keep conditions constant throughout

92
Q

what happens to the guard cells when the plant has lots of water ?

A

guard cells fill with water and go plump and turgid

93
Q

what happens when the guard cells go plump and turgid ?

A

the stomata opens up so gases can be exchanged for photosynthesis

94
Q

what happens to the guard cells when the plant is short of water ?

A
  • guard cells lose water and become flaccid
95
Q

what happens when the guard cells go flaccid ?

A

the stomata will close to stop water vapour from escaping

96
Q

how are the outer and inner walls of the guard cells adapted to their function ?

A
  • they are sensitive to light and close at night to save water
97
Q

why are stomata on the underside of the leaf ?

A

so they are in a more shaded and cooled area so less water is lost through the stomata

98
Q

describe how to investigate stomata and guard cells ?

A
  • peel the epidermis straight of the leaf and mount onto a microscope slide with a cover slip
  • as you can’t peel the top layer of the surface of use a clear nail varnish and dry it, use a piece of sticky tape to remove the varnish of the leaf by gently peeling it off and stick with sticky tape onto a microscope slide
  • view the slide under the microscope
  • estimate the total number of stomata with a sample - using what you can see in your field of vision and repeat 3 times
  • estimate how many times the field of vision would fit into the stomata by finding the area of the field and dividing by the total area of the surface
  • multiply your answer by the average number of stomata per field of vision

do this in different areas of the leaf to compare how different parts of the leaf has different distribution of stomata

99
Q

what do you need when investigating the distribution of stomata ?

A

a light microscope

100
Q

what is health ?

A

the state of physical and mental wellbeing

101
Q

what is a communicable disease ?

A

diseases which can be spread from person to person or between animals and people

102
Q

what are the 2 types of diseases ?

A

communicable
non-communicable

103
Q

what are non-communicable diseases ?

A

diseases which cannot spread

104
Q

how long do non- communicable diseases last ?

A

a long time

105
Q

what is a communicable disease also known as ?

A

infectious or contagious diseases

106
Q

what affects health ?

A
  • diet
  • stress
  • life situation
107
Q

what is cardiovascular disease ?

A

a term used to describe diseases of the heart or blood vessels

108
Q

give an example of a cardiovascular disease ?

A

coronary heart disease

109
Q

what is coronary heart disease ?

A

when the arteries that supply blood to the heart muscle is blocked by layers of fatty material building up, causing arteries to become narrow

110
Q

what are the affects of coronary heart disease ?

A

blood flow is restricted and there’s a lack of oxygen to the heart muscle which can cause a heart attack

111
Q

what is a stent ?

A

wire mesh tubes

112
Q

what are stents used for ?

A

they are inserted inside arteries to widen them and keep them open

113
Q

what diseases are stents used for ?

A

coronary heart disease

114
Q

how do stents help with coronary heart disease ?

A

they keep coronary arteries open, making sure blood can pass through to the heart muscles, keeping the persons heart beating

115
Q

what are the advantages of stents ?

A
  • they lower the risk of heart attack
  • effective for a long time
  • recovery time from surgery is quick
116
Q

what are the disadvantages of stents ?

A

risk of infections during surgery
risk of blood clot

117
Q

what is thormbosis ?

A

the risk of a blood clot from stents

118
Q

what are statins ?

A

drugs that reduce the amount of ‘bad’ cholesterol present in the bloodstream

119
Q

what is cholesterol ?

A

an essential lipid that your body produces to function properly

120
Q

what is bad cholesterol known as ?

A

LDL cholesterol

121
Q

what can LDL cholesterol cause ?

A

fatty deposits to form inside arteries

122
Q

what do statins help stop ?

A

fatty deposits inside arteries forming

123
Q

what are the advantages of statins ?

A
  • can reduce the risk of strokes, coronary heart disease, heart attacks
  • increases the amount of good- HDL cholesterol in your bloodstream
  • removing LDL cholesterol can remove other diseases
124
Q

what is good cholesterol called ?

A

HDL cholesterol

125
Q

what is the disadvantage of statins ?

A
  • they need to be taken regularly
  • headaches
  • kidney failure
  • memory loss
  • they don’t kick in instantly
126
Q

if someone needs a heart transplant but donor organs aren’t available what can be done ?

A

artificial hearts may be used

127
Q

what are artificial hearts ?

A

mechanical devices that pump blood for a person who’s own heart has failed

128
Q

are artificial hearts usually temporary or permanent ?

A

temporary

129
Q

what are the advantages of artificial hearts?

A
  • less likely to be rejected by the body’s immune system than a donor heart
130
Q

why are artificial hearts less likely to be rejected than a donor heart ?

A

they are made from metals or plastics so the body doesn’t recognise them as foreign

131
Q

what are the disadvantages of artificial hearts ?

A
  • surgery can lead to bleeding and infection
  • don’t work as well as healthy ones
  • parts of the heart could wear out and fail
  • blood doesn’t flow as smoothly which can cause blood clots
  • when recieving an artificial heart patient has to take drugs to thin their blood so clots don’t occurr - this can lead to issues if injured as blood can’t help clot to heal wounds
  • uncomfortable
132
Q

why can valves stop working ?

A

damaged by heart attacks
old age

133
Q

what can damage to valves cause ?

A

valve tissue to stiffen so it doesn’t open properly, or a valve may be leaky

134
Q

what can a leaky valve cause ?

A

blood to flow both ways

135
Q

how can valves be replaced ?

A

biological valves
mechanical valves

136
Q

what are biological valves ?

A

valves taken from mammals

137
Q

what are mechanical valves ?

A

man-made valves

138
Q

what are the disadvantages of valve replacements ?

A

blood clots can happen

139
Q

what is artificial blood ?

A

a blood substitute e.g a salt solution (saline) which is used to replace a lost volume of blood

140
Q

what are risk factors ?

A

things that are linked to an increase in the liklelihood that a person will develop a certain disease during their lifetime

141
Q

what can risk factors be ?

A
  • aspects of a persons life
  • substances in the environment
142
Q

where are the risks of non-communicable diseases higher and why ?

A

in deprived areas because people are more likely to smoke, not exercise and have a good diet

in higher income diseases because they eat more processed food

143
Q

give examples of risk factors which cause disease ?

A
  • smoking
  • obesity
  • drinking alcohol
  • smoking when pregnant
144
Q

what are human costs of non-communicable diseases ?

A
  • millions of people die
  • people have lower qualities of life
  • shorter lifespans
145
Q

what are the financial costs of non-communicable diseases ?

A
  • cost of researching and treating the disease is huge
  • families may have to move homes or adapt their life which can be costly
  • if people are ill they can’t work = can effect economy if many people are ill
146
Q

what is cancer caused by ?

A

uncontrolled cell growth and division which occurs change to the cells and causes a tumour

147
Q

what is a tumour ?

A

a growth of abnormal cells

148
Q

what are the 2 types of tumours ?

A

benign
malignant

149
Q

what are benign tumours ?

A

where tumours grow until there’s no room - the tumour stays in 1 place rather than invading other tissues in the body

150
Q

are benign tumours dangerous ?

A

no

151
Q

what are malignant tumours ?

A

where a tumour grows and spreads to neighboring healthy tissues - it can cause cells to break off and spread to other parts of the body travelling in the bloodstream

152
Q

what do malignant tumours form ?

A

secondary tumours

153
Q

are malignant tumours dangerous ?

A

yes - they are cancers

154
Q

give risks of cancer ?

A
  • smoking
  • obesity
  • UV exposure
  • viral infection
155
Q

what are genetic risk factors of cancer ?

A

genes you inherit from your parents can be faulty increasing risks to cancer

mutations in BRCA genes increase chances of breast and ovarian cancer

156
Q

what are enzymes ?

A

biological catalysts and speed up useful chemical reactions in the body

157
Q

why do reactions in the body need to be carefully controlled ?

A

to get the right amounts of substances

158
Q

how can you make a reaction happen more quickly ?

A

by increasing the temperature

159
Q

why is increasing the temperature not good to speed up a reaction inside the body ?

A

it can speed up unwanted reactions which can damage cells

160
Q

what is catalyst ?

A

a substance which increases the speed of a reaction without being changed or used up in the reaction

161
Q

what are enzymes made up of ?

A

large proteins
made up of chains of amino acids

162
Q

why are enzymes amino acid chains all different shapes ?

A

as they all have different jobs

163
Q

what does every enzyme have ?

A

an active site

164
Q

what is an active site ?

A

a unique shape that fits onto the substance involved in the reaction

165
Q

why do enzymes only catalyse for 1 specific reaction ?

A

the substrate has to fit into its unique active site

166
Q

what is the locke and key theory ?

A

each enzyme has a uniquely shaped active site where only 1 substrate can fit into it to form the products, like a lock and key

167
Q

what is an induced fit ?

A

where the active site changes slightly as the substrate binds to it to get a tighter fit

168
Q

what is an optimum condition ?

A

the best conditions

169
Q

how can temperature effect enzyme action ?

A

the higher the temperature, the faster the rate at first

if it gets too hot the bonds holding the enzyme together will break which changes the shape of the enzymes active site so the substrate won’t fit into it anymore = denatured

170
Q

what does denatured mean ?

A

the temperature has got too hot the the substrate will no longer fit into the enzymes active site

171
Q

what is the optimum temperature for enzyme action in the human body?

A

37 degrees

172
Q

how does PH affect enzyme action ?

A

it it is too high or low, the PH interferes with the bonds holding the enzyme together which can change the shape of the active site and denatures the enzyme

173
Q

what is the optimum PH for lots of enzymes and why ?

A

PH 7 -because its neutral

174
Q

what does the enzyme amylase do ?

A

breakdown starch into maltose

175
Q

how do you detect starch ?

A

using iodine if starch is present, solution will turn from orangey-brown to blue-black

176
Q

describe how PH effects amylase activityexperiment ?

A
  1. put a drop of iodine solution on a spotting tile
  2. place a bunsen burner and heat water over it until is reaches 35 degrees
  3. use a syringe to add 1cm cubed of amylase solution and 1cm of a buffer solution with a PH 5 to a boiling tube, using test tube holders, put the boiling tube into a beaker of water and wait 5 minutes
  4. use a different syringe to add 5cm cubed of starch solution to the boiling tube
  5. mix the contents of the boiling tube and start a stopwatch
  6. use continuous sampling to record how long it takes for amylase to break down all the starch by using a dropping pipette to take a fresh sample from the boiling tube every 30 seconds and put into a well
  7. when iodine remains brown, starch is no longer present
  8. repeat with buffer solutions of different pH to see how pH affects the time taken for starch to be broken down
177
Q

how do you calculate rate of reaction when investigating pH on amylase ?

A

1000/time

178
Q

what are the units for rate of reaction when investigating pH on amylase ?

A

s-1

179
Q

what is the digestive system ?

A

an organ system that breaks down food so nutrients can be absorbed into your body from the gut

180
Q

how is food broken down ?

A

mechanical digestion
chemical digestion

181
Q

what is mechanical digestion ?

A

teeth grinding food down

182
Q

what is chemical digestion ?

A

enzymes help to break down food

183
Q

how are enzymes involved in digestion produced ?

A

by specialised cells in glands and in the gut lining and then released into the gut to mix with food molecules

184
Q

what happens to starch, proteins and lipids when they want to pass through the digestive system ?

A

digestive enzymes break these big molecules down into smaller ones which are soluble and can pass easily through the walls of the digestive system allowing them to be absorbed into the bloodstream

185
Q

what can the products of digestion be used to make ?

A

new carbohydrates, proteins and lipids

186
Q

what do the carbohydrase enzymes break down ?

A

carbohydrates into simple sugars

187
Q

give an example of a carbohydydrase ?

A

amylase - it breaks down starch

188
Q

where is amylase ?

A

salivary glands
pancreas
small intestine

189
Q

what are protease enzymes ?

A

digestive enzymes that catalyse the convertion of proteins into amino acids

190
Q

where are proteases made ?

A

stomach
pancreas
snall intestine

191
Q

where does amylase work ?

A

mouth
small intestine

192
Q

where do proteases work ?

A

stomach
small intestine

193
Q

what are lipase enzymes ?

A

digestive enzymes that catalyse the conversion of lipids into glycerol and fatty acids

194
Q

where are lipases made ?

A

pancreas
small intestine

195
Q

where do lipases work ?

A

small intestine

196
Q

where is bile produced ?

A

in the liver

197
Q

where is bile stored ?

A

the gall bladder before it is released into the small intestine

198
Q

what does bile do ?

A

neutralises and makes the conditions alkaline in the small intestine because the hydrochloric acid in the stomach` makes it too acidic for enzymes in the small intestine to work properly

199
Q

what does bile do to fats ?

A

breaks them into tiny droplets which gives a much bigger surface area for lipase to work on - makes digestion quicker

200
Q

how do you prepare a food sample ?

A

1- break up food using a pestle and mortar
2- transfer the ground up food to a beaker and add distilled water
3- stir the mixture with a glass rod to dissolve the food
4- filter the solution using a funnel lined with filter paper which will get rid of the solid bits of food

201
Q

what are the 2 types of sugars ?

A

non-reducing
reducing

202
Q

how do you test for reducing sugars ?

A

using Benedicts test

203
Q

how do you carry out Benedicts test ?

A
  • prepare food sample and transfer 5cm3 to a test tube
  • prepare water bath at 75 c
  • add benedicts solution to the test tube
  • place the test tube in the water bath and leave for 5 minutes
  • if the food sample contains a reducing sugar the solution will change from blue to green , yellow or brick red
204
Q

what does the colour the sugar solution will turn depend on ?

A

how sugary it is - the more sugar - the more red

205
Q

how do you test for starch ?

A

1 - make a food sample and transfer 5cm3 to a test tube
2- add drops of iodine solution and shake the tube
3- if sample contains starch - colour of solution changes from orangey brown to blue black

206
Q

what solution do you use to test for starch ?

A

iodine

207
Q

how can you test for protein ?

A
  • prepare a sample and transfer 2cm3 to a test tube
  • add 2cm3 of Biuret solution to the sample and mix the contents of the food by shaking it
  • if the food sample contains protein solution will change from blue to purple
208
Q

what solution do you use to test for protein ?

A

biuret solution

209
Q

how do you test for lipids ?

A

1- prepare food sample but do not filter, add 5cm3 to a test tube
2- use a pipette to add 3 drops of Sudan III stain solution to test tube and shake
3- if the food sample has lipids the mixture will separate into 2 layers
- the top layer will be bright red
- if no lipids form no separate layer will form at the top of the liquid

210
Q

what tests for lipids and how ?

A

Sudan III stain
it stains lipids

gcse science (27 decks)

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