Page 105 - General and Inorganic Chemistry for Advanced Secondary Schools Students Book Form Five and Six

Biology for Secondary Schools
(d) They have suckers, hooks, or both
for attachment to the host.
Advantages of platyhelminths
(a) Some flatworms, such as planaria
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are scavengers, feeding on organic
particles from dead bodies of other
organisms.
(b) Some are used as biological
specimens in the field of education
and medicine. Examples of such
flatworms include tapeworms and
liver flukes.
Disadvantages of platyhelminths
Task 5.11
Search from reliable internet sources the
videos or images showing beef or pork
infected with tapeworms. Note down
what you have observed.
(a) Many species are parasites
that cause diseases to humans, (c) They cause general body weakness
livestock and wild animals. For
example:
(i) Tapeworm causes taeniasis,
which is an intestinal tapeworm
infection transmitted through
consuming raw or undercooked
beef or pork infected with
tapeworms. The infection (d) Parasitic flatworms can also
caused by larval stages of
tapeworms can lead to heart
attack or epilepsy. If the
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Biology FORM 1 new.indd 99
Biology FORM 1 new.indd 99
infection is located in the heart
muscles it can cause heart
attack and if it is located in
the brain, it can cause epilepsy.
(ii) Liver fluke causes fascioliasis.
This disease causes liver rot
in sheep, cattle and humans.
(iii) Some species of blood flukes,
such as Schistosoma spp. cause
bilharzia (schistosomiasis). If
untreated it may cause urinary
bladder cancer or intestinal
cancer.
(b) Parasitic flatworms can cause
reduction in quality and amount
of meat and milk produced by
livestock due to infections. They
can also cause stunted growth and
even death in young animals.
and frequent hunger in the hosts
as they feed on digested nutrients
from the hosts. Working animals,
such as oxen cannot perform work
to their full capacity if infected
with a large number of parasitic
flatworms.
cause loss of income due to costs
incurred for treatment of diseases.
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15/10/2024 09:24:34