Revision cue cards for B3

Topics – B3 Unit 1
Revision cards
Print out. Fold left to write and test yourself / get someone
to test you!!
NB: The topics in green are the ones you should revise
for the end of year test.
Osmosis (Q)
1. Name three ways substances can
move in and out of cells
2. Describe osmosis
3. What is a partially permeable
4. What happens to plant cells when
they are put into a weak solution /
5. What can happen to animal cells
when put into a very dilute
6. Why do animal cells but not plant
cells burst when they take up
Sports drinks
Active transport
Exchange surfaces
Gas exchange in the lungs
Exchange in plants
Rates of transpiration
The circulatory system
The heart
Arteries and veins
Blood cells
Transport in plants
Osmosis (A)
1. Osmosis, diffusion, active transport
2. The movement of water from a high to
low concentration down a concentration
gradient across a partially permeable
3. A membrane with small holes that
allows some substances (like small
water molecules) to pass through but
will not allow larger molecules through.
4. The pressure in the cells will increase as
water will enter via osmosis.
5. Water will enter animal cell via osmosis
but they can burst (called lysis)
6. Plant cells have a cell wall which
prevents the cell from bursting. Animal
cells do not have a cell wall
Sports Drinks (Q)
1. Why do humans need water?
2. What is the recommended intake of
water for adults?
3. When would you need more water?
4. What substances do you lose when you
5. Why do we sweat more when we
6. What do sports drinks contain?
(Don’t worry about q.7)
7. What are the three types of sports
Active transport (Q)
1. What are the three features of active
transport that makes it different from
other methods?
2. What is the energy used for in active
3. Give examples of where active
transport may occur
4. Explain how active transport enables
mineral ions to be taken up by the plant
Sports Drinks (A)
1. To prevent dehydration. Cells do not function
properly without water. To protect organs,
substances are dissolved in water, temperature
regulation, lubricate the joints.
2. Two to three litres of water per day to remain
3. During exercise, hot day (sweat more).
4. Water and salt ions.
5. When we exercise we use energy which is released
from sugars during respiration. This generates
heats, so to cool your body you sweat.
6. Water – hydration, carbohydrates – for energy,
mineral ions – healthy muscles, caffeine –
7. Hypotonic – hydration, isotonic – fuel and
hydration, hypertonic - fuel
Active transport (A)
1. Against a concentration gradient (from low to
high), requires a carrier protein to pass
through the membrane, Requires ATP (energy)
from respiration.
2. To change the shape of the protein carrier
3. Plant roots, the villi of the small intestine, the
absorption of sugars from cells
4. Mineral ions are at low concentration in the
soil, lower than in the plant cells. The minerals
cannot move into the cell by diffusion. They use
active transport.
Exchange surfaces (Q)
1. Why does the process of exchange
become inefficient in larger organisms?
2. Give examples of different exchange
3. What are the three main features of
exchange surfaces?
Gas exchange in the lungs (Q)
1. Where does gas exchange in the lungs
2. Which gases are exchanged in the
3. What causes the ribcage to move up and
down during ventilation?
4. What is the role of the diaphragm when
you breathe in?
5. What is the percentage of oxygen and
carbon dioxide in inhaled and exhaled
Exchange surfaces (A)
1. Their surface area to volume ratio
becomes smaller so exchange in
2. Surface of the lungs (alveoli), the
surfaces of gills, the digestive system
(villi in the small intestine), the leaf
(gases), plant roots.
3. Large surface area, thin surface
(short distances), excellent blood
supply maintains concentration
Gas exchange in the lungs (A)
1. The alveoli
2. Oxygen and carbon dioxide
3. The intercostal muscles contract, this
causes the ribs to move up and expands
the thorax
4. The diaphragm flattens expanding the
space in the thorax decreasing the
pressure so air rushes in
5. Inhaled air – Oxygen 21%, carbon
dioxide 0.04%. Exhaled air – oxygen
17%, carbon dioxide 4%
Gas exchange in plants (Q)
1. By what process does water move into
the plant roots?
2. Where does water enter and leave a
3. State two uses of water by the plant
4. How can plants reduce water loss?
5. How do the guard cells control the
water loss through the stomata?
6. What substances are exchanged
through the stoma?
7. What is transpiration?
Rates of transpiration (Q)
1. What factors affects the rate of
2. What is used to measure the
rates of transpiration?
3. Why do gardeners need to
water their plants more in
4. Why will sand dune plants
loose more water than
woodland plants?
5. Why do florist spray their
plants will water?
Gas exchange in plants (A)
1. Osmosis
2. Enters through the roots, leaves through the
stomata in the leaves
3. Water is used for photosynthesis, when water
leaves the plant it cools the plant, helps to support
the plant, transports dissolved minerals
4. Most stomata are on the underside of the leaf (the
coolest part), the guard cells will close the stoma.
5. When there is plenty of light and water the guard
cells swell and become firm by osmosis this causes
them to bend and opens the stoma. When there
isn’t enough water the guard cells lose water via
osmosis and cannot open.
6. Water vapour leaves the plant, carbon dioxide
enters the leaf if the stoma are open and used for
photosynthesis, oxygen leaves through the stoma
produced as a byproduct of photosynthesis
7. Water flows up the stem and through the leaves
before leaving the leaves by evaporation via stoma
Rates of transpiration (A)
1. Light intensity, temperature, air
movement, humidity.
2. A photometer
3. The rates of transpiration will be greater
because the stomata are open allowing
more gas exchange for photosynthesis
4. Sand dunes are windier and will carry
the evaporated water molecules away
from the leaf increasing the
concentration gradient.
5. Increasing the humidity prevents plants
loosing water by reducing the
concentration gradient
The circulatory system (Q)
The circulatory system (A)
1. Name three substances that blood carries
to your body cells
2. Name two substances that blood carries
away from your body cells
3. What are blood expanders and when might
they be used?
4. What are oxygen carriers?
5. Why might the remaining haemoglobin in
a trauma patients blood be enough to
sustain a motionless patient but not a
mobile one?
6. Give the advantages of artificial blood
1. Oxygen , glucose, amino acids, nutrients,
2. Urea, carbon dioxide,
3. Sterile saline solutions that maintain normal blood
pressure so blood can flow if patients have lost a
lot of blood. Used in emergency situations
4. If two thirds of your blood is lost you would need
artificial blood that would carrier oxygen. Can be
chemicals that release oxygen or can be
encapsulated haemoglobin
5. Motionless patients will not need as much energy
and will respire less needing less oxygen
6. Don’t have to be matched to patients, useful for
treating war casualties, in countries where
transfusions aren’t safe (not screened for disease),
for trauma patients, can be stored for three years
at room temp, immediately restore full oxygen
carrying capacity (real blood takes 24hrs)
The heart (Q)
The heart (A)
1. What are the names of the four chambers
of the heart
2. Which side pumps oxygenated blood to the
3. What is the artery called that carries
oxygenated blood to the body?
4. Which artery pumps deoxygenated blood
to the lungs?
5. Which blood vessels carries deoxygenated
blood towards to the heart?
6. Why are artificial heart valves made of
inert materials?
7. Why would the risk of rejection be a
serious problem if artificial hearts had a
capillary blood supply?
1. The right and left ventricle, the
right and left atria
2. The left side
3. The aorta
4. The pulmonary artery
5. The vena cava
6. Prevents corrosion / reaction sin
the body. Smooth to prevent blood
7. The white blood cells would patrol
the heart and attack it if the
artificial heart had a capillary blood
Arteries and Veins (Q)
1. Why is the lining of the
arteries folded?
2. Why does measuring you
pulse allow you to measure
your heart rate?
3. Identify the features of
4. Identify the features of
5. What is a stent?
6. Who might need a stent?
Capillaries (Q)
1. Describe the structure of the
2. What is the function of the
3. What substances are carried to
your cells by the capillaries?
4. What waste substances do the
capillaries remove from the
Arteries and Veins (A)
1. Allows them to stretch and recoil when blood
enters and is pumped under high pressure
2. Each pulse corresponds to each beat of your
3. Usually carry deoxygenated blood back to the
heart. Large lumen, have valves to prevent
backflow, smooth lining, thin walls, little
muscle or elastic as the blood is under low
4. Usually carry oxygenated blood away from the
heart. Elastic fibres, muscle fibres, narrow
lumen, folded inner lining that expands with
each high pressure blood spurt.
5. A narrow mesh tube that can be inserted into
blocked / narrowed artery to widen the lumen
and allow the blood to flow through.
6. People at risk of a heart attack due to narrowed
arteries blocked by saturated fat deposits.
Capillaries (A)
1. Their wall is one cell thick for efficient
exchange, blood is under low pressure so
as not to damage the blood vessels, lumen
diameter is wide enough to let one red
blood cell through at a time. Blood flow is
very slow, form vast networks at the
tissues of every organ – they have a large
surface area.
2. To deliver blood to your tissues allowing
exchange of substances
3. Oxygen for respiration, glucose for
respiration, amino acids for growth and
repair, other nutrients like fatty acids,
water – hydration and hormones.
4. Carbon dioxide, lactic acid (anaerobic
respiration), urea, spent hormones, heat
Blood (Q)
Blood (A)
1. What makes blood a unique tissue?
2. Where in your body is blood made?
3. State three functions of the blood
4. Name four substances carried in your
5. Name four substances dissolved in
6. How does your blood protect you?
7. How does your body regulate heat?
8. Why is it important to maintain a
constant pH?
Blood Cells (Q)
1. What is the function of red
blood cells?
2. How are red blood cells
adapted to their function?
3. What are the functions of
white blood cells?
4. Why can’t red blood cells
5. Where are old red blood cells
broken down?
6. What do platelets do?
It is the only tissue on your body that is a fluid
The bone marrow
transport, protection, regulation of body
temperature and pH
oxygen, carbon dioxide, glucose, amino acids,
hormones, cholesterol, mineral ions, antibodies,
fatty acids
carbon dioxide, glucose, amino acids, hormones,
cholesterol, mineral ions, antibodies, fatty acids
Blood clots forming scabs at wounds to prevent
microbes entering and stops blood loss. White
blood cells fight invading pathogens
Distributes heat from respiring muscles to other
organs and your skin
Enzymes require a specific pH to function or they
will change shape (denature)
Blood Cells (A)
1. To carry oxygen to your tissues for
2. They are biconcave – large surface area, no
nucleus – more space for oxygen, contain
haemoglobin which forms
oxyhaeomoglobin when combined with
3. Defence against pathogens. Produce
antitoxins and antibodies. Some ingest
foreign particles.
4. They have no nucleus
5. The liver
6. Small cell fragments no nucleus. Help the
blood to clot. Made in the bone marrow.
Transport in plants (Q)
1. What are the two vascular
bundles of plants?
2. What do the vascular
bundles do?
3. What do the xylem do?
4. What do the phloem do?
5. What is transpiration
6. What is translocation?
Topics – B3 Unit 2
Keeping internal conditions constant
The kidney
Renal dialysis
Kidney transplants
Decreasing body temperature
Increasing body temperature
Regulating glucose levels
Type 1 diabetes
Human populations
Global warming
Microbes and food production
Food chains and food production
Transport in plants (A)
1. Xylem and phloem
2. Transport substances from the roots
through the stem to the leaves and they
provide support.
3. Dead cells stacked on top of each other
forming long hollow tubes. They transport
water and dissolved substances from the
roots to the leaves
4. Living cells that form tubes and transport
food substances in both directions
5. The continual transport of water from the
roots to the leaves by xylem
6. The transport of sugars made by
photosynthesis in the leaf to areas where
the plant needs it – for storage / growing
areas by the phloem
Keeping internal conditions constant (Q)
1. If your muscles respire anaerobically
which waste product do they produce?
2. How is the waste product of anaerobic
respiration harmful if it isn’t removed?
3. What is the process called where waste
products are removed from the body
4. Name five internal conditions that must
be kept constant
5. What does ammonia react with to make
6. How is urea harmful to the body?
7. Why must temperature be regulated?
8. Why must blood sugar be regulated?
The kidney (Q)
Keeping internal conditions constant (A)
1. Lactic acid
2. Increases blood pH which can prevent
enzymatic reactions
3. Excretion
4. pH, Water, ion content, temperature, blood
sugar levels
5. carbon dioxide
6. makes the blood alkaline which affects the
7. Proteins and cell membranes would
become damaged above or below 36 –
8. Needed for respiration. Too little – tired
and faint. Too much and water would leave
the cells by osmosis
The kidney (A)
How is urea made in the body?
Proteins digested into amino
Which organ removes urea?
acids. Excess amino acids are carried by the
How is urea transported from the liver
blood to your liver and are converted to
to the kidneys?
ammonia. This reacts with carbon dioxide
Why is the glucose that is filtered from
and it becomes urea.
the kidneys reabsorbed?
The kidneys
Apart from urea what else does the
kidney regulate?
Via blood
How would a high protein diet affect
Glucose is useful for respiration
the levels of urea?
Excess salt ions and water
How would the water content of your
Increase the amount of urea
urine change if the weather was hot but you didn’t 6.
Urine would be very
drink any water
concentrated, little water
How would your urine change if you
ate a very salty meal?
The urine would become very
Renal Dialysis (Q)
Renal Dialysis (A)
1. What is renal failure?
2. Explain the difference between acute and chronic
renal failure
3. Why does the renal dialysis fluid have to be
4. Why is the dialysis fluid at body temperature?
5. Why is heparin added to the patients blood before
the blood enters the dialysis machine?
6. Why does the dialysis fluid contain glucose at the
same concentration as a healthy human?
7. Why does the renal dialysis fluid have to be
changed after a dialysis session?
1. Condition where the kidneys don’t function properly
2. Acute – sudden, but treatable. Usually caused by an
infection or drugs. Chronic – long lasting and patients
will not recover. Could be genetic or due to diabetes.
Symptoms include sickness, paralysis, back pain,
anaemia, swollen limbs
3. To prevent infections
4. To prevent the patient loosing or gaining heat
5. It is an anticoagulant which prevents the blood from
6. So that the concentration of glucose will not change – it
won't diffuse through the membrane
7. The dialysis fluid will contain the patients excess salt
and water
8. Renal failure disrupts the ion concentration in the cells
and so cells may take up extra water to balance the
concentration inside the cells which contain excess ions
Kidney transplants (Q)
1. What are the advantages of
having a kidney transplant
compared with renal dialysis?
2. What precautions do medical
teams take to reduce the risk of
rejection when transplanting a
3. Why are transplant patients
more at risk of infection?
4. Explain why a recipient may
reject a transplanted kidney?
Kidney transplants (A)
8. Why do you think people with renal
dialysis get swollen ankles, feet, face and
1. improved quality of life (no more
dialysis 4 times per week, can go on
holiday) / Cheaper for NHS to
2. Tissue type the patient and the
donor, match blood types closely
3. They have to take
immunosuppressant drugs to
prevent the immune system
attacking the transplanted organ
4. The recipients immune system can
recognize that the antigens on the
transplanted kidney are not their
own. The white blood cells would
then attack and destroy the organ
Decreasing your body temperature
1. Why can exercise cause us to overheat?
2. Why can dehydration increase the chance
of overheating?
3. How does sweating cool you?
4. Why does your skin look and feel red and
hot when you are overheating?
5. Why should we drink more during hot
6. Describe vasodilation
7. Where is the thermoregulatory centre?
8. How do dogs cool themselves?
9. Elephants and rabbit have large ears, how
does this help them to cool?
Decreasing your body temperature (A)
1. Increases respiration which produces heat as a
2. Water needed to distribute the heat in our blood
between our organs and to the skin where the heat
can radiate out. Water is needed for sweat
3. Sweating cools the body because the water
evaporates and takes the heat away with it.
4. The blood vessels open wide to let the heat radiate
from the surface
5. We sweat more so we need to replace the water
6. Nerves stimulate the blood vessels that supply the
capillaries in the skin. They dilate and this allows
more blood to flow to the surface. The excess heat
radiates away from the body
7. The brain
8. They pant instead of sweating
9. Large surface area allows the heat to radiate away
from their bodies.
Increasing your body temperature
Increasing your body temperature
1. Enzymes will not work properly and chemical
1. Why is it dangerous if your core
reactions will slow down. You will become
body temperature drops below
35 C
2. Reduced heat loss by evaporation
3. Outside in cold weather too long, immersed in cold
2. Why does reduced sweating
water, elderly, a baby (large surface area to
prevent you from overcooling
volume ratio
3. State two reasons why you may
4. Stimulates the skeletal muscles to contract and
relax quickly which requires energy from
respiration. Respiration produces heat.
4. How does shivering warm you up? 5. The arterioles that supply the capillaries near the
5. What is vasoconstriction?
skin contrast preventing blood flowing at the skins
surface. Your skin will look pale and feel cold. This
conserves heat and protects internal organs from
heat loss and damage. Prolonged exposure would
result in frost bite
Regulating blood glucose levels (Q)
1. Explain why blood glucose level rises after you
have eaten a meal?
2. Why does your blood glucose level drop when you
have not eaten for several hours?
3. Explain why your blood glucose level drops after
you have been swimming?
4. Which organ monitors your blood glucose levels?
5. Which hormone is released into your blood when
your blood glucose level rises above normal
6. Which hormone is released into your blood when
your blood glucose levels are lower than normal?
7. What does insulin do?
8. Which of the are carbohydrates and which are
Glucagon, glucose, glycogen, insulin
Type 1 diabetes (Q)
1. What is type 1 diabetes?
2. How is type 1 diabetes
3. What would happen if people
with type 1 diabetes did not
get treatment?
4. What causes type 1 diabetes?
5. Why do people with diabetes
urinate very frequently?
Regulating blood glucose levels (A)
1. the digested carbohdrates (glucose)
enters your blood via the walls of the
small intestine
2. The glucose is used up during
3. Exercise usues energy which is made
during respiration. Glucose is needed for
4. The pancreas
5. Insulin
6. Glucagon
7. Insulin promotes the uptake of glucose
into cells. Takes excess glucose to the
liver to be stored as insoluble glycogen
8. Carbs: Glucose, glycogen. Proteins:
Glucagon, Insulin
Type 1 diabetes (A)
1. Where patients do not make enough insulin
and so blood glucose level is not controlled.
2. Injections of insulin into blood after meals, eat
regular high fiber meals, monitor blood glucose
levels, avoid alcohol, take regular exercise
3. Blindness due to retina damage, poor wound
healing, ulcers, increased risk of stroke,
increased risk of heart attack
4. Cells of the patients immune system destroy
the special cells in the pancreas which
produces insulin. Could be caused by viral
infection, cows milk in early life, certain
antibiotics and trauma injury or pancreatic
5. When the kidneys filter the blood too much
glucose is filtered out and the kidneys do not
reabsorb the glucose. Glucose passes out of the
urine and a lot of water goes with it. This is also
why diabetics feel very thirsty
Human Populations (Q)
Human Populations (A)
1. Many children died young, lack of contraception
1. Families had large numbers of
2. Diet improved, hygiene improved, healthcare
children before 1900. Suggest
improve, infant mortality fell
3. Shortage of food in some countries, more land
being used for farming and building, more pollution
2. After 1900 there was a dramatic
being produced, the world’s resources are being
used faster than they can be replaced
rise in the population. Suggest
4. Sustainable means using resources for human
reasons why
needs without harming the environment
5. Recycle, replace resources where possible (plant
3. Population increase has negative
new trees), avoid over use of resources if they
effects on the environment.
cannot be replaced quickly eg fishing quotas. Use
Suggest these negative effects.
alternative fuels
4. Describe the meaning of the term
5. How can humans manage their use
of resources?
Pollution (Q)
Pollution (A)
1. Cows produce methane – greenhouse gas which
1. List three ways in which farming
contributes to global warming, the use of
can damage the environment
fertilisers can run off the soil polluting the rivers
2. How does sulphur dioxide produce
which can cause eutrophication and the use of
pesticides / herbicides which can wash into
acid rain?
waterways and build up in the food chain to toxic
3. What is the affect of carbon
dioxide released from cars
2. The sulphur dissolves in rain to form acid rain
3. This greenhouse gas contributes to global
factories, burning wood?
4. Why are people in towns only
4. Smoke causes smog and the smoke particles can
allowed to burn smokeless fuel?
cause bronchitis or prevent photosynthesis
5. What are the problems with CFCs? 5. CFCs damage the ozone layer allowing more UV
rays in
Deforestation (Q)
State two major reasons for deforestation
What are the effects of deforestation?
What is peat?
What are the negative consequences of
destroying and removing peat from peat
How do trees prevent erosion?
Why is the drugs industry concerned with
How could humans use wood more
Explain three ways in which deforestation
results in carbon dioxide release
Global warming (Q)
1. Which two gases are the main
greenhouses gases?
2. What are the major sources of
these gases?
3. Why has there been an increase in
the two major greenhouse gases?
4. Why is global warming affecting
the polar bear distribution?
5. How can carbon dioxide be
removed from the atmosphere
Deforestation (A)
To provide timber for furniture, building and fuel and for
creating land for farming / building
Increases CO2 (global warming), loss of biodiversity, soil
erosion, loss of future resources
Produced over thousands of years from moss in wet acidic
boggy areas. It is very rich in nutrients and has been dug up
and sold for compost
loss of a diverse habitat, when the moss is aerated it begins
to decay which releases carbon dioxide into the atmosphere
and contributes to global warming
No tree roots to hold the soil in place. No trees to take up the
Some undiscovered species will become extinct before their
properties have been researched for medicinal properties, to
treat diseases.
Recycle wood / paper products. Plant new trees for every
tree cut down.
Slash and burn – removing the trees which take in carbon
dioxide when they photosynthesize. Burning the trees which
release carbon dioxide when they burn. The release of
carbon dioxide from the microbes that decompose the
decaying material
Global warming (A)
1. Methane and carbon dioxide
2. Methane from cattle farming and rice
paddy fields. Carbon dioxide from
increased combustion (burning) of fossil
fuels to supply us with energy.
3. Increased combustion demand for
energy. Increased demand for meat –
more farming
4. Global warming is increasing sea
temperatures which melts the ice caps.
Polar bears have less ice to live on
5. Trees and plants take up carbon dioxide
by photosynthesis
Biofuels (Q)
1. What is the energy source for
making biofuels?
2. Name the three types of biofuels
3. State the advantages and
disadvantages of biofuels
4. Why is biogas from landfill sites
particularly dangerous?
5. Why is gasohol used in Brazil?
6. Why do we describe biogas as
carbon neutral?
Biofuels (A)
1. The sunlight used in photosynthesis
2. Wood, Biogas, Bioethanol,
3. Advantages: Reduces fossil fuel usage by
providing an alternative fuel, no overall
increase in the level of carbon dioxide,
doesn’t produce particulates.
Disadvantages: habitat loss, extinction of
4. It could explode
5. Lots of sugar cane – can be made into
6. The carbon dioxide taken in during the
growing of the biofuels in photosynthesis is
released again when the fuel is burnt
Microbes and food production (Q)
Microbes and food production (Q)
1. Name a fungi that can be eaten
1. Mushrooms
2. Alcohol and bread
2. Name two food products produced
3. A high protein low fat meat
by yeasts
substitute that can be flavoured
3. What is mycoprotein?
made from a fungus
4. What conditions must be kept
4. The pH and the temperature
constant in the production of
5. High protein, high fibre, low fat.
5. How nutritional is mycoprotein?
Food chains and food production (Q)
Food chains and food production (A)
1. How is energy lost from a food chain?
2. Why is it more efficient for humans to eat
herbivores and producers rather than
3. How do farmers maximize energy
4. How would controlling the temperature of
animals reduce energy loss?
5. How would reducing movement reduce
energy loss?
6. List the advantages of energy efficiency
7. List the disadvantages of energy efficient
1. movement, keeping warm, excretion, reproduction
2. Shorter food chain means less energy is lost.
Carnivores will not contain as much energy
3. Reduce animal movement / control the
temperature of their animals
4. Warm: Reduce heat loss, less energy wasted in
keeping warm.
5. Reduced respiration
6. Less energy transferred out of the food chain,
more available for human consumption, less
labour intensive, less risk of attack from predators
like foxes, cheaper to produce
7. Greater risk of disease spreading between animals,
inhumane / cruel, poor quality product
Fishing (Q)
1. What technological advances led to
2. Which fish species are caught in
UK waters?
3. Which fish species is most likely to
disappear from the North Atlantic?
4. What actions have governments
taken to prevent overfishing?
5. How effective have these
strategies been?
6. What is the disadvantage of these
Fishing (A)
1. Sonar to locate the fish, sophisticated nets
designed to prevent fish escaping, well
designed boats that can travel long
distances and can store fish in big freezers
2. Herring, haddock, cod and mackerel
3. Cod
4. Net size – larger holes to allow younger fish
to escape and breed – replenish the
population and fishing quotas – prevent
endangered species from being overfished
5. Fishing in the North sea is now sustainable.
Fishing has been reduced to a level where
the fish populations are able to recover.
6. Fishermen are suffering unemployment
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